Google Git
Sign in
flutter / mirrors / flutter / refs/heads/flutter-3.14-candidate.0 / . / packages / flutter / lib / src / material / date_picker.dart
blob: 93c699cc9d7f3ff3da57bca2a1317a70793be5b0 [file] [log] [blame] [edit]
// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'dart:math' as math;
import 'package:flutter/rendering.dart';
import 'package:flutter/services.dart';
import 'package:flutter/widgets.dart';
import 'app_bar.dart';
import 'back_button.dart';
import 'button_style.dart';
import 'calendar_date_picker.dart';
import 'color_scheme.dart';
import 'date.dart';
import 'date_picker_theme.dart';
import 'debug.dart';
import 'dialog.dart';
import 'dialog_theme.dart';
import 'divider.dart';
import 'icon_button.dart';
import 'icons.dart';
import 'ink_well.dart';
import 'input_border.dart';
import 'input_date_picker_form_field.dart';
import 'input_decorator.dart';
import 'material.dart';
import 'material_localizations.dart';
import 'material_state.dart';
import 'scaffold.dart';
import 'text_button.dart';
import 'text_field.dart';
import 'text_theme.dart';
import 'theme.dart';
// The M3 sizes are coming from the tokens, but are hand coded,
// as the current token DB does not contain landscape versions.
const Size _calendarPortraitDialogSizeM2 = Size(330.0, 518.0);
const Size _calendarPortraitDialogSizeM3 = Size(328.0, 512.0);
const Size _calendarLandscapeDialogSize = Size(496.0, 346.0);
const Size _inputPortraitDialogSizeM2 = Size(330.0, 270.0);
const Size _inputPortraitDialogSizeM3 = Size(328.0, 270.0);
const Size _inputLandscapeDialogSize = Size(496, 160.0);
const Size _inputRangeLandscapeDialogSize = Size(496, 164.0);
const Duration _dialogSizeAnimationDuration = Duration(milliseconds: 200);
const double _inputFormPortraitHeight = 98.0;
const double _inputFormLandscapeHeight = 108.0;
const double _kMaxTextScaleFactor = 1.3;
/// Shows a dialog containing a Material Design date picker.
///
/// The returned [Future] resolves to the date selected by the user when the
/// user confirms the dialog. If the user cancels the dialog, null is returned.
///
/// When the date picker is first displayed, it will show the month of
/// [initialDate], with [initialDate] selected.
///
/// The [firstDate] is the earliest allowable date. The [lastDate] is the latest
/// allowable date. [initialDate] must either fall between these dates,
/// or be equal to one of them. For each of these [DateTime] parameters, only
/// their dates are considered. Their time fields are ignored. They must all
/// be non-null.
///
/// The [currentDate] represents the current day (i.e. today). This
/// date will be highlighted in the day grid. If null, the date of
/// `DateTime.now()` will be used.
///
/// An optional [initialEntryMode] argument can be used to display the date
/// picker in the [DatePickerEntryMode.calendar] (a calendar month grid)
/// or [DatePickerEntryMode.input] (a text input field) mode.
/// It defaults to [DatePickerEntryMode.calendar] and must be non-null.
///
/// {@template flutter.material.date_picker.switchToInputEntryModeIcon}
/// An optional [switchToInputEntryModeIcon] argument can be used to
/// display a custom Icon in the corner of the dialog
/// when [DatePickerEntryMode] is [DatePickerEntryMode.calendar]. Clicking on
/// icon changes the [DatePickerEntryMode] to [DatePickerEntryMode.input].
/// If null, `Icon(useMaterial3 ? Icons.edit_outlined : Icons.edit)` is used.
/// {@endtemplate}
///
/// {@template flutter.material.date_picker.switchToCalendarEntryModeIcon}
/// An optional [switchToCalendarEntryModeIcon] argument can be used to
/// display a custom Icon in the corner of the dialog
/// when [DatePickerEntryMode] is [DatePickerEntryMode.input]. Clicking on
/// icon changes the [DatePickerEntryMode] to [DatePickerEntryMode.calendar].
/// If null, `Icon(Icons.calendar_today)` is used.
/// {@endtemplate}
///
/// An optional [selectableDayPredicate] function can be passed in to only allow
/// certain days for selection. If provided, only the days that
/// [selectableDayPredicate] returns true for will be selectable. For example,
/// this can be used to only allow weekdays for selection. If provided, it must
/// return true for [initialDate].
///
/// The following optional string parameters allow you to override the default
/// text used for various parts of the dialog:
///
/// * [helpText], label displayed at the top of the dialog.
/// * [cancelText], label on the cancel button.
/// * [confirmText], label on the ok button.
/// * [errorFormatText], message used when the input text isn't in a proper date format.
/// * [errorInvalidText], message used when the input text isn't a selectable date.
/// * [fieldHintText], text used to prompt the user when no text has been entered in the field.
/// * [fieldLabelText], label for the date text input field.
///
/// An optional [locale] argument can be used to set the locale for the date
/// picker. It defaults to the ambient locale provided by [Localizations].
///
/// An optional [textDirection] argument can be used to set the text direction
/// ([TextDirection.ltr] or [TextDirection.rtl]) for the date picker. It
/// defaults to the ambient text direction provided by [Directionality]. If both
/// [locale] and [textDirection] are non-null, [textDirection] overrides the
/// direction chosen for the [locale].
///
/// The [context], [barrierDismissible], [barrierColor], [barrierLabel],
/// [useRootNavigator] and [routeSettings] arguments are passed to [showDialog],
/// the documentation for which discusses how it is used.
/// [context], [barrierDismissible] and [useRootNavigator] must be non-null.
///
/// The [builder] parameter can be used to wrap the dialog widget
/// to add inherited widgets like [Theme].
///
/// An optional [initialDatePickerMode] argument can be used to have the
/// calendar date picker initially appear in the [DatePickerMode.year] or
/// [DatePickerMode.day] mode. It defaults to [DatePickerMode.day], and
/// must be non-null.
///
/// {@macro flutter.widgets.RawDialogRoute}
///
/// ### State Restoration
///
/// Using this method will not enable state restoration for the date picker.
/// In order to enable state restoration for a date picker, use
/// [Navigator.restorablePush] or [Navigator.restorablePushNamed] with
/// [DatePickerDialog].
///
/// For more information about state restoration, see [RestorationManager].
///
/// {@macro flutter.widgets.RestorationManager}
///
/// {@tool dartpad}
/// This sample demonstrates how to create a restorable Material date picker.
/// This is accomplished by enabling state restoration by specifying
/// [MaterialApp.restorationScopeId] and using [Navigator.restorablePush] to
/// push [DatePickerDialog] when the button is tapped.
///
/// ** See code in examples/api/lib/material/date_picker/show_date_picker.0.dart **
/// {@end-tool}
///
/// See also:
///
/// * [showDateRangePicker], which shows a Material Design date range picker
/// used to select a range of dates.
/// * [CalendarDatePicker], which provides the calendar grid used by the date picker dialog.
/// * [InputDatePickerFormField], which provides a text input field for entering dates.
/// * [DisplayFeatureSubScreen], which documents the specifics of how
/// [DisplayFeature]s can split the screen into sub-screens.
/// * [showTimePicker], which shows a dialog that contains a Material Design time picker.
///
Future<DateTime?> showDatePicker({
required BuildContext context,
required DateTime initialDate,
required DateTime firstDate,
required DateTime lastDate,
DateTime? currentDate,
DatePickerEntryMode initialEntryMode = DatePickerEntryMode.calendar,
SelectableDayPredicate? selectableDayPredicate,
String? helpText,
String? cancelText,
String? confirmText,
Locale? locale,
bool barrierDismissible = true,
Color? barrierColor,
String? barrierLabel,
bool useRootNavigator = true,
RouteSettings? routeSettings,
TextDirection? textDirection,
TransitionBuilder? builder,
DatePickerMode initialDatePickerMode = DatePickerMode.day,
String? errorFormatText,
String? errorInvalidText,
String? fieldHintText,
String? fieldLabelText,
TextInputType? keyboardType,
Offset? anchorPoint,
final ValueChanged<DatePickerEntryMode>? onDatePickerModeChange,
final Icon? switchToInputEntryModeIcon,
final Icon? switchToCalendarEntryModeIcon,
}) async {
initialDate = DateUtils.dateOnly(initialDate);
firstDate = DateUtils.dateOnly(firstDate);
lastDate = DateUtils.dateOnly(lastDate);
assert(
!lastDate.isBefore(firstDate),
'lastDate $lastDate must be on or after firstDate $firstDate.',
);
assert(
!initialDate.isBefore(firstDate),
'initialDate $initialDate must be on or after firstDate $firstDate.',
);
assert(
!initialDate.isAfter(lastDate),
'initialDate $initialDate must be on or before lastDate $lastDate.',
);
assert(
selectableDayPredicate == null || selectableDayPredicate(initialDate),
'Provided initialDate $initialDate must satisfy provided selectableDayPredicate.',
);
assert(debugCheckHasMaterialLocalizations(context));
Widget dialog = DatePickerDialog(
initialDate: initialDate,
firstDate: firstDate,
lastDate: lastDate,
currentDate: currentDate,
initialEntryMode: initialEntryMode,
selectableDayPredicate: selectableDayPredicate,
helpText: helpText,
cancelText: cancelText,
confirmText: confirmText,
initialCalendarMode: initialDatePickerMode,
errorFormatText: errorFormatText,
errorInvalidText: errorInvalidText,
fieldHintText: fieldHintText,
fieldLabelText: fieldLabelText,
keyboardType: keyboardType,
onDatePickerModeChange: onDatePickerModeChange,
switchToInputEntryModeIcon: switchToInputEntryModeIcon,
switchToCalendarEntryModeIcon: switchToCalendarEntryModeIcon,
);
if (textDirection != null) {
dialog = Directionality(
textDirection: textDirection,
child: dialog,
);
}
if (locale != null) {
dialog = Localizations.override(
context: context,
locale: locale,
child: dialog,
);
}
return showDialog<DateTime>(
context: context,
barrierDismissible: barrierDismissible,
barrierColor: barrierColor,
barrierLabel: barrierLabel,
useRootNavigator: useRootNavigator,
routeSettings: routeSettings,
builder: (BuildContext context) {
return builder == null ? dialog : builder(context, dialog);
},
anchorPoint: anchorPoint,
);
}
/// A Material-style date picker dialog.
///
/// It is used internally by [showDatePicker] or can be directly pushed
/// onto the [Navigator] stack to enable state restoration. See
/// [showDatePicker] for a state restoration app example.
///
/// See also:
///
/// * [showDatePicker], which is a way to display the date picker.
class DatePickerDialog extends StatefulWidget {
/// A Material-style date picker dialog.
DatePickerDialog({
super.key,
required DateTime initialDate,
required DateTime firstDate,
required DateTime lastDate,
DateTime? currentDate,
this.initialEntryMode = DatePickerEntryMode.calendar,
this.selectableDayPredicate,
this.cancelText,
this.confirmText,
this.helpText,
this.initialCalendarMode = DatePickerMode.day,
this.errorFormatText,
this.errorInvalidText,
this.fieldHintText,
this.fieldLabelText,
this.keyboardType,
this.restorationId,
this.onDatePickerModeChange,
this.switchToInputEntryModeIcon,
this.switchToCalendarEntryModeIcon,
}) : initialDate = DateUtils.dateOnly(initialDate),
firstDate = DateUtils.dateOnly(firstDate),
lastDate = DateUtils.dateOnly(lastDate),
currentDate = DateUtils.dateOnly(currentDate ?? DateTime.now()) {
assert(
!this.lastDate.isBefore(this.firstDate),
'lastDate ${this.lastDate} must be on or after firstDate ${this.firstDate}.',
);
assert(
!this.initialDate.isBefore(this.firstDate),
'initialDate ${this.initialDate} must be on or after firstDate ${this.firstDate}.',
);
assert(
!this.initialDate.isAfter(this.lastDate),
'initialDate ${this.initialDate} must be on or before lastDate ${this.lastDate}.',
);
assert(
selectableDayPredicate == null || selectableDayPredicate!(this.initialDate),
'Provided initialDate ${this.initialDate} must satisfy provided selectableDayPredicate',
);
}
/// The initially selected [DateTime] that the picker should display.
final DateTime initialDate;
/// The earliest allowable [DateTime] that the user can select.
final DateTime firstDate;
/// The latest allowable [DateTime] that the user can select.
final DateTime lastDate;
/// The [DateTime] representing today. It will be highlighted in the day grid.
final DateTime currentDate;
/// The initial mode of date entry method for the date picker dialog.
///
/// See [DatePickerEntryMode] for more details on the different data entry
/// modes available.
final DatePickerEntryMode initialEntryMode;
/// Function to provide full control over which [DateTime] can be selected.
final SelectableDayPredicate? selectableDayPredicate;
/// The text that is displayed on the cancel button.
final String? cancelText;
/// The text that is displayed on the confirm button.
final String? confirmText;
/// The text that is displayed at the top of the header.
///
/// This is used to indicate to the user what they are selecting a date for.
final String? helpText;
/// The initial display of the calendar picker.
final DatePickerMode initialCalendarMode;
/// The error text displayed if the entered date is not in the correct format.
final String? errorFormatText;
/// The error text displayed if the date is not valid.
///
/// A date is not valid if it is earlier than [firstDate], later than
/// [lastDate], or doesn't pass the [selectableDayPredicate].
final String? errorInvalidText;
/// The hint text displayed in the [TextField].
///
/// If this is null, it will default to the date format string. For example,
/// 'mm/dd/yyyy' for en_US.
final String? fieldHintText;
/// The label text displayed in the [TextField].
///
/// If this is null, it will default to the words representing the date format
/// string. For example, 'Month, Day, Year' for en_US.
final String? fieldLabelText;
/// {@template flutter.material.datePickerDialog}
/// The keyboard type of the [TextField].
///
/// If this is null, it will default to [TextInputType.datetime]
/// {@endtemplate}
final TextInputType? keyboardType;
/// Restoration ID to save and restore the state of the [DatePickerDialog].
///
/// If it is non-null, the date picker will persist and restore the
/// date selected on the dialog.
///
/// The state of this widget is persisted in a [RestorationBucket] claimed
/// from the surrounding [RestorationScope] using the provided restoration ID.
///
/// See also:
///
/// * [RestorationManager], which explains how state restoration works in
/// Flutter.
final String? restorationId;
/// Called when the [DatePickerDialog] is toggled between
/// [DatePickerEntryMode.calendar],[DatePickerEntryMode.input].
///
/// An example of how this callback might be used is an app that saves the
/// user's preferred entry mode and uses it to initialize the
/// `initialEntryMode` parameter the next time the date picker is shown.
final ValueChanged<DatePickerEntryMode>? onDatePickerModeChange;
/// {@macro flutter.material.date_picker.switchToInputEntryModeIcon}
final Icon? switchToInputEntryModeIcon;
/// {@macro flutter.material.date_picker.switchToCalendarEntryModeIcon}
final Icon? switchToCalendarEntryModeIcon;
@override
State<DatePickerDialog> createState() => _DatePickerDialogState();
}
class _DatePickerDialogState extends State<DatePickerDialog> with RestorationMixin {
late final RestorableDateTime _selectedDate = RestorableDateTime(widget.initialDate);
late final _RestorableDatePickerEntryMode _entryMode = _RestorableDatePickerEntryMode(widget.initialEntryMode);
final _RestorableAutovalidateMode _autovalidateMode = _RestorableAutovalidateMode(AutovalidateMode.disabled);
@override
String? get restorationId => widget.restorationId;
@override
void restoreState(RestorationBucket? oldBucket, bool initialRestore) {
registerForRestoration(_selectedDate, 'selected_date');
registerForRestoration(_autovalidateMode, 'autovalidateMode');
registerForRestoration(_entryMode, 'calendar_entry_mode');
}
final GlobalKey _calendarPickerKey = GlobalKey();
final GlobalKey<FormState> _formKey = GlobalKey<FormState>();
void _handleOk() {
if (_entryMode.value == DatePickerEntryMode.input || _entryMode.value == DatePickerEntryMode.inputOnly) {
final FormState form = _formKey.currentState!;
if (!form.validate()) {
setState(() => _autovalidateMode.value = AutovalidateMode.always);
return;
}
form.save();
}
Navigator.pop(context, _selectedDate.value);
}
void _handleCancel() {
Navigator.pop(context);
}
void _handleOnDatePickerModeChange() {
widget.onDatePickerModeChange?.call(_entryMode.value);
}
void _handleEntryModeToggle() {
setState(() {
switch (_entryMode.value) {
case DatePickerEntryMode.calendar:
_autovalidateMode.value = AutovalidateMode.disabled;
_entryMode.value = DatePickerEntryMode.input;
_handleOnDatePickerModeChange();
case DatePickerEntryMode.input:
_formKey.currentState!.save();
_entryMode.value = DatePickerEntryMode.calendar;
_handleOnDatePickerModeChange();
case DatePickerEntryMode.calendarOnly:
case DatePickerEntryMode.inputOnly:
assert(false, 'Can not change entry mode from ${_entryMode.value}');
}
});
}
void _handleDateChanged(DateTime date) {
setState(() {
_selectedDate.value = date;
});
}
Size _dialogSize(BuildContext context) {
final bool useMaterial3 = Theme.of(context).useMaterial3;
final Orientation orientation = MediaQuery.orientationOf(context);
switch (_entryMode.value) {
case DatePickerEntryMode.calendar:
case DatePickerEntryMode.calendarOnly:
switch (orientation) {
case Orientation.portrait:
return useMaterial3 ? _calendarPortraitDialogSizeM3 : _calendarPortraitDialogSizeM2;
case Orientation.landscape:
return _calendarLandscapeDialogSize;
}
case DatePickerEntryMode.input:
case DatePickerEntryMode.inputOnly:
switch (orientation) {
case Orientation.portrait:
return useMaterial3 ? _inputPortraitDialogSizeM3 : _inputPortraitDialogSizeM2;
case Orientation.landscape:
return _inputLandscapeDialogSize;
}
}
}
static const Map<ShortcutActivator, Intent> _formShortcutMap = <ShortcutActivator, Intent>{
// Pressing enter on the field will move focus to the next field or control.
SingleActivator(LogicalKeyboardKey.enter): NextFocusIntent(),
};
@override
Widget build(BuildContext context) {
final ThemeData theme = Theme.of(context);
final bool useMaterial3 = theme.useMaterial3;
final MaterialLocalizations localizations = MaterialLocalizations.of(context);
final Orientation orientation = MediaQuery.orientationOf(context);
final DatePickerThemeData datePickerTheme = DatePickerTheme.of(context);
final DatePickerThemeData defaults = DatePickerTheme.defaults(context);
final TextTheme textTheme = theme.textTheme;
// There's no M3 spec for a landscape layout input (not calendar)
// date picker. To ensure that the date displayed in the input
// date picker's header fits in landscape mode, we override the M3
// default here.
TextStyle? headlineStyle;
if (useMaterial3) {
headlineStyle = datePickerTheme.headerHeadlineStyle ?? defaults.headerHeadlineStyle;
switch (_entryMode.value) {
case DatePickerEntryMode.input:
case DatePickerEntryMode.inputOnly:
if (orientation == Orientation.landscape) {
headlineStyle = textTheme.headlineSmall;
}
case DatePickerEntryMode.calendar:
case DatePickerEntryMode.calendarOnly:
// M3 default is OK.
}
} else {
headlineStyle = orientation == Orientation.landscape ? textTheme.headlineSmall : textTheme.headlineMedium;
}
final Color? headerForegroundColor = datePickerTheme.headerForegroundColor ?? defaults.headerForegroundColor;
headlineStyle = headlineStyle?.copyWith(color: headerForegroundColor);
final Widget actions = Container(
alignment: AlignmentDirectional.centerEnd,
constraints: const BoxConstraints(minHeight: 52.0),
padding: const EdgeInsets.symmetric(horizontal: 8),
child: OverflowBar(
spacing: 8,
children: <Widget>[
TextButton(
onPressed: _handleCancel,
child: Text(widget.cancelText ?? (
useMaterial3
? localizations.cancelButtonLabel
: localizations.cancelButtonLabel.toUpperCase()
)),
),
TextButton(
onPressed: _handleOk,
child: Text(widget.confirmText ?? localizations.okButtonLabel),
),
],
),
);
CalendarDatePicker calendarDatePicker() {
return CalendarDatePicker(
key: _calendarPickerKey,
initialDate: _selectedDate.value,
firstDate: widget.firstDate,
lastDate: widget.lastDate,
currentDate: widget.currentDate,
onDateChanged: _handleDateChanged,
selectableDayPredicate: widget.selectableDayPredicate,
initialCalendarMode: widget.initialCalendarMode,
);
}
Form inputDatePicker() {
return Form(
key: _formKey,
autovalidateMode: _autovalidateMode.value,
child: Container(
padding: const EdgeInsets.symmetric(horizontal: 24),
height: orientation == Orientation.portrait ? _inputFormPortraitHeight : _inputFormLandscapeHeight,
child: Shortcuts(
shortcuts: _formShortcutMap,
child: Column(
children: <Widget>[
const Spacer(),
InputDatePickerFormField(
initialDate: _selectedDate.value,
firstDate: widget.firstDate,
lastDate: widget.lastDate,
onDateSubmitted: _handleDateChanged,
onDateSaved: _handleDateChanged,
selectableDayPredicate: widget.selectableDayPredicate,
errorFormatText: widget.errorFormatText,
errorInvalidText: widget.errorInvalidText,
fieldHintText: widget.fieldHintText,
fieldLabelText: widget.fieldLabelText,
keyboardType: widget.keyboardType,
autofocus: true,
),
const Spacer(),
],
),
),
),
);
}
final Widget picker;
final Widget? entryModeButton;
switch (_entryMode.value) {
case DatePickerEntryMode.calendar:
picker = calendarDatePicker();
entryModeButton = IconButton(
icon: widget.switchToInputEntryModeIcon ?? Icon(useMaterial3 ? Icons.edit_outlined : Icons.edit),
color: headerForegroundColor,
tooltip: localizations.inputDateModeButtonLabel,
onPressed: _handleEntryModeToggle,
);
case DatePickerEntryMode.calendarOnly:
picker = calendarDatePicker();
entryModeButton = null;
case DatePickerEntryMode.input:
picker = inputDatePicker();
entryModeButton = IconButton(
icon: widget.switchToCalendarEntryModeIcon ?? const Icon(Icons.calendar_today),
color: headerForegroundColor,
tooltip: localizations.calendarModeButtonLabel,
onPressed: _handleEntryModeToggle,
);
case DatePickerEntryMode.inputOnly:
picker = inputDatePicker();
entryModeButton = null;
}
final Widget header = _DatePickerHeader(
helpText: widget.helpText ?? (
useMaterial3
? localizations.datePickerHelpText
: localizations.datePickerHelpText.toUpperCase()
),
titleText: localizations.formatMediumDate(_selectedDate.value),
titleStyle: headlineStyle,
orientation: orientation,
isShort: orientation == Orientation.landscape,
entryModeButton: entryModeButton,
);
// Constrain the textScaleFactor to the largest supported value to prevent
// layout issues.
final double textScaleFactor = MediaQuery.textScalerOf(context).clamp(maxScaleFactor: _kMaxTextScaleFactor).textScaleFactor;
final Size dialogSize = _dialogSize(context) * textScaleFactor;
final DialogTheme dialogTheme = theme.dialogTheme;
return Dialog(
backgroundColor: datePickerTheme.backgroundColor ?? defaults.backgroundColor,
elevation: useMaterial3
? datePickerTheme.elevation ?? defaults.elevation!
: datePickerTheme.elevation ?? dialogTheme.elevation ?? 24,
shadowColor: datePickerTheme.shadowColor ?? defaults.shadowColor,
surfaceTintColor: datePickerTheme.surfaceTintColor ?? defaults.surfaceTintColor,
shape: useMaterial3
? datePickerTheme.shape ?? defaults.shape
: datePickerTheme.shape ?? dialogTheme.shape ?? defaults.shape,
insetPadding: const EdgeInsets.symmetric(horizontal: 16.0, vertical: 24.0),
clipBehavior: Clip.antiAlias,
child: AnimatedContainer(
width: dialogSize.width,
height: dialogSize.height,
duration: _dialogSizeAnimationDuration,
curve: Curves.easeIn,
child: MediaQuery.withClampedTextScaling(
// Constrain the textScaleFactor to the largest supported value to prevent
// layout issues.
maxScaleFactor: _kMaxTextScaleFactor,
child: Builder(builder: (BuildContext context) {
switch (orientation) {
case Orientation.portrait:
return Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
header,
if (useMaterial3) Divider(height: 0, color: datePickerTheme.dividerColor),
Expanded(child: picker),
actions,
],
);
case Orientation.landscape:
return Row(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
header,
if (useMaterial3) VerticalDivider(width: 0, color: datePickerTheme.dividerColor),
Flexible(
child: Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
Expanded(child: picker),
actions,
],
),
),
],
);
}
}),
),
),
);
}
}
// A restorable [DatePickerEntryMode] value.
//
// This serializes each entry as a unique `int` value.
class _RestorableDatePickerEntryMode extends RestorableValue<DatePickerEntryMode> {
_RestorableDatePickerEntryMode(
DatePickerEntryMode defaultValue,
) : _defaultValue = defaultValue;
final DatePickerEntryMode _defaultValue;
@override
DatePickerEntryMode createDefaultValue() => _defaultValue;
@override
void didUpdateValue(DatePickerEntryMode? oldValue) {
assert(debugIsSerializableForRestoration(value.index));
notifyListeners();
}
@override
DatePickerEntryMode fromPrimitives(Object? data) => DatePickerEntryMode.values[data! as int];
@override
Object? toPrimitives() => value.index;
}
// A restorable [AutovalidateMode] value.
//
// This serializes each entry as a unique `int` value.
class _RestorableAutovalidateMode extends RestorableValue<AutovalidateMode> {
_RestorableAutovalidateMode(
AutovalidateMode defaultValue,
) : _defaultValue = defaultValue;
final AutovalidateMode _defaultValue;
@override
AutovalidateMode createDefaultValue() => _defaultValue;
@override
void didUpdateValue(AutovalidateMode? oldValue) {
assert(debugIsSerializableForRestoration(value.index));
notifyListeners();
}
@override
AutovalidateMode fromPrimitives(Object? data) => AutovalidateMode.values[data! as int];
@override
Object? toPrimitives() => value.index;
}
/// Re-usable widget that displays the selected date (in large font) and the
/// help text above it.
///
/// These types include:
///
/// * Single Date picker with calendar mode.
/// * Single Date picker with text input mode.
/// * Date Range picker with text input mode.
///
/// [helpText], [orientation], [icon], [onIconPressed] are required and must be
/// non-null.
class _DatePickerHeader extends StatelessWidget {
/// Creates a header for use in a date picker dialog.
const _DatePickerHeader({
required this.helpText,
required this.titleText,
this.titleSemanticsLabel,
required this.titleStyle,
required this.orientation,
this.isShort = false,
this.entryModeButton,
});
static const double _datePickerHeaderLandscapeWidth = 152.0;
static const double _datePickerHeaderPortraitHeight = 120.0;
static const double _headerPaddingLandscape = 16.0;
/// The text that is displayed at the top of the header.
///
/// This is used to indicate to the user what they are selecting a date for.
final String helpText;
/// The text that is displayed at the center of the header.
final String titleText;
/// The semantic label associated with the [titleText].
final String? titleSemanticsLabel;
/// The [TextStyle] that the title text is displayed with.
final TextStyle? titleStyle;
/// The orientation is used to decide how to layout its children.
final Orientation orientation;
/// Indicates the header is being displayed in a shorter/narrower context.
///
/// This will be used to tighten up the space between the help text and date
/// text if `true`. Additionally, it will use a smaller typography style if
/// `true`.
///
/// This is necessary for displaying the manual input mode in
/// landscape orientation, in order to account for the keyboard height.
final bool isShort;
final Widget? entryModeButton;
@override
Widget build(BuildContext context) {
final DatePickerThemeData themeData = DatePickerTheme.of(context);
final DatePickerThemeData defaults = DatePickerTheme.defaults(context);
final Color? backgroundColor = themeData.headerBackgroundColor ?? defaults.headerBackgroundColor;
final Color? foregroundColor = themeData.headerForegroundColor ?? defaults.headerForegroundColor;
final TextStyle? helpStyle = (themeData.headerHelpStyle ?? defaults.headerHelpStyle)?.copyWith(
color: foregroundColor,
);
final Text help = Text(
helpText,
style: helpStyle,
maxLines: 1,
overflow: TextOverflow.ellipsis,
);
final Text title = Text(
titleText,
semanticsLabel: titleSemanticsLabel ?? titleText,
style: titleStyle,
maxLines: orientation == Orientation.portrait ? 1 : 2,
overflow: TextOverflow.ellipsis,
);
switch (orientation) {
case Orientation.portrait:
return SizedBox(
height: _datePickerHeaderPortraitHeight,
child: Material(
color: backgroundColor,
child: Padding(
padding: const EdgeInsetsDirectional.only(
start: 24,
end: 12,
bottom: 12,
),
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
const SizedBox(height: 16),
help,
const Flexible(child: SizedBox(height: 38)),
Row(
children: <Widget>[
Expanded(child: title),
if (entryModeButton != null)
entryModeButton!,
],
),
],
),
),
),
);
case Orientation.landscape:
return SizedBox(
width: _datePickerHeaderLandscapeWidth,
child: Material(
color: backgroundColor,
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
const SizedBox(height: 16),
Padding(
padding: const EdgeInsets.symmetric(
horizontal: _headerPaddingLandscape,
),
child: help,
),
SizedBox(height: isShort ? 16 : 56),
Expanded(
child: Padding(
padding: const EdgeInsets.symmetric(
horizontal: _headerPaddingLandscape,
),
child: title,
),
),
if (entryModeButton != null)
Padding(
padding: const EdgeInsets.symmetric(horizontal: 4),
child: entryModeButton,
),
],
),
),
);
}
}
}
/// Shows a full screen modal dialog containing a Material Design date range
/// picker.
///
/// The returned [Future] resolves to the [DateTimeRange] selected by the user
/// when the user saves their selection. If the user cancels the dialog, null is
/// returned.
///
/// If [initialDateRange] is non-null, then it will be used as the initially
/// selected date range. If it is provided, `initialDateRange.start` must be
/// before or on `initialDateRange.end`.
///
/// The [firstDate] is the earliest allowable date. The [lastDate] is the latest
/// allowable date. Both must be non-null.
///
/// If an initial date range is provided, `initialDateRange.start`
/// and `initialDateRange.end` must both fall between or on [firstDate] and
/// [lastDate]. For all of these [DateTime] values, only their dates are
/// considered. Their time fields are ignored.
///
/// The [currentDate] represents the current day (i.e. today). This
/// date will be highlighted in the day grid. If null, the date of
/// `DateTime.now()` will be used.
///
/// An optional [initialEntryMode] argument can be used to display the date
/// picker in the [DatePickerEntryMode.calendar] (a scrollable calendar month
/// grid) or [DatePickerEntryMode.input] (two text input fields) mode.
/// It defaults to [DatePickerEntryMode.calendar] and must be non-null.
///
/// {@macro flutter.material.date_picker.switchToInputEntryModeIcon}
///
/// {@macro flutter.material.date_picker.switchToCalendarEntryModeIcon}
///
/// The following optional string parameters allow you to override the default
/// text used for various parts of the dialog:
///
/// * [helpText], the label displayed at the top of the dialog.
/// * [cancelText], the label on the cancel button for the text input mode.
/// * [confirmText],the label on the ok button for the text input mode.
/// * [saveText], the label on the save button for the fullscreen calendar
/// mode.
/// * [errorFormatText], the message used when an input text isn't in a proper
/// date format.
/// * [errorInvalidText], the message used when an input text isn't a
/// selectable date.
/// * [errorInvalidRangeText], the message used when the date range is
/// invalid (e.g. start date is after end date).
/// * [fieldStartHintText], the text used to prompt the user when no text has
/// been entered in the start field.
/// * [fieldEndHintText], the text used to prompt the user when no text has
/// been entered in the end field.
/// * [fieldStartLabelText], the label for the start date text input field.
/// * [fieldEndLabelText], the label for the end date text input field.
///
/// An optional [locale] argument can be used to set the locale for the date
/// picker. It defaults to the ambient locale provided by [Localizations].
///
/// An optional [textDirection] argument can be used to set the text direction
/// ([TextDirection.ltr] or [TextDirection.rtl]) for the date picker. It
/// defaults to the ambient text direction provided by [Directionality]. If both
/// [locale] and [textDirection] are non-null, [textDirection] overrides the
/// direction chosen for the [locale].
///
/// The [context], [barrierDismissible], [barrierColor], [barrierLabel],
/// [useRootNavigator] and [routeSettings] arguments are passed to [showDialog],
/// the documentation for which discusses how it is used.
/// [context], [barrierDismissible] and [useRootNavigator] must be non-null.
///
/// The [builder] parameter can be used to wrap the dialog widget
/// to add inherited widgets like [Theme].
///
/// {@macro flutter.widgets.RawDialogRoute}
///
/// ### State Restoration
///
/// Using this method will not enable state restoration for the date range picker.
/// In order to enable state restoration for a date range picker, use
/// [Navigator.restorablePush] or [Navigator.restorablePushNamed] with
/// [DateRangePickerDialog].
///
/// For more information about state restoration, see [RestorationManager].
///
/// {@macro flutter.widgets.RestorationManager}
///
/// {@tool sample}
/// This sample demonstrates how to create a restorable Material date range picker.
/// This is accomplished by enabling state restoration by specifying
/// [MaterialApp.restorationScopeId] and using [Navigator.restorablePush] to
/// push [DateRangePickerDialog] when the button is tapped.
///
/// ** See code in examples/api/lib/material/date_picker/show_date_range_picker.0.dart **
/// {@end-tool}
///
/// See also:
///
/// * [showDatePicker], which shows a Material Design date picker used to
/// select a single date.
/// * [DateTimeRange], which is used to describe a date range.
/// * [DisplayFeatureSubScreen], which documents the specifics of how
/// [DisplayFeature]s can split the screen into sub-screens.
Future<DateTimeRange?> showDateRangePicker({
required BuildContext context,
DateTimeRange? initialDateRange,
required DateTime firstDate,
required DateTime lastDate,
DateTime? currentDate,
DatePickerEntryMode initialEntryMode = DatePickerEntryMode.calendar,
String? helpText,
String? cancelText,
String? confirmText,
String? saveText,
String? errorFormatText,
String? errorInvalidText,
String? errorInvalidRangeText,
String? fieldStartHintText,
String? fieldEndHintText,
String? fieldStartLabelText,
String? fieldEndLabelText,
Locale? locale,
bool barrierDismissible = true,
Color? barrierColor,
String? barrierLabel,
bool useRootNavigator = true,
RouteSettings? routeSettings,
TextDirection? textDirection,
TransitionBuilder? builder,
Offset? anchorPoint,
TextInputType keyboardType = TextInputType.datetime,
final Icon? switchToInputEntryModeIcon,
final Icon? switchToCalendarEntryModeIcon,
}) async {
assert(
initialDateRange == null || !initialDateRange.start.isAfter(initialDateRange.end),
"initialDateRange's start date must not be after it's end date.",
);
initialDateRange = initialDateRange == null ? null : DateUtils.datesOnly(initialDateRange);
firstDate = DateUtils.dateOnly(firstDate);
lastDate = DateUtils.dateOnly(lastDate);
assert(
!lastDate.isBefore(firstDate),
'lastDate $lastDate must be on or after firstDate $firstDate.',
);
assert(
initialDateRange == null || !initialDateRange.start.isBefore(firstDate),
"initialDateRange's start date must be on or after firstDate $firstDate.",
);
assert(
initialDateRange == null || !initialDateRange.end.isBefore(firstDate),
"initialDateRange's end date must be on or after firstDate $firstDate.",
);
assert(
initialDateRange == null || !initialDateRange.start.isAfter(lastDate),
"initialDateRange's start date must be on or before lastDate $lastDate.",
);
assert(
initialDateRange == null || !initialDateRange.end.isAfter(lastDate),
"initialDateRange's end date must be on or before lastDate $lastDate.",
);
currentDate = DateUtils.dateOnly(currentDate ?? DateTime.now());
assert(debugCheckHasMaterialLocalizations(context));
Widget dialog = DateRangePickerDialog(
initialDateRange: initialDateRange,
firstDate: firstDate,
lastDate: lastDate,
currentDate: currentDate,
initialEntryMode: initialEntryMode,
helpText: helpText,
cancelText: cancelText,
confirmText: confirmText,
saveText: saveText,
errorFormatText: errorFormatText,
errorInvalidText: errorInvalidText,
errorInvalidRangeText: errorInvalidRangeText,
fieldStartHintText: fieldStartHintText,
fieldEndHintText: fieldEndHintText,
fieldStartLabelText: fieldStartLabelText,
fieldEndLabelText: fieldEndLabelText,
keyboardType: keyboardType,
switchToInputEntryModeIcon: switchToInputEntryModeIcon,
switchToCalendarEntryModeIcon: switchToCalendarEntryModeIcon,
);
if (textDirection != null) {
dialog = Directionality(
textDirection: textDirection,
child: dialog,
);
}
if (locale != null) {
dialog = Localizations.override(
context: context,
locale: locale,
child: dialog,
);
}
return showDialog<DateTimeRange>(
context: context,
barrierDismissible: barrierDismissible,
barrierColor: barrierColor,
barrierLabel: barrierLabel,
useRootNavigator: useRootNavigator,
routeSettings: routeSettings,
useSafeArea: false,
builder: (BuildContext context) {
return builder == null ? dialog : builder(context, dialog);
},
anchorPoint: anchorPoint,
);
}
/// Returns a locale-appropriate string to describe the start of a date range.
///
/// If `startDate` is null, then it defaults to 'Start Date', otherwise if it
/// is in the same year as the `endDate` then it will use the short month
/// day format (i.e. 'Jan 21'). Otherwise it will return the short date format
/// (i.e. 'Jan 21, 2020').
String _formatRangeStartDate(MaterialLocalizations localizations, DateTime? startDate, DateTime? endDate) {
return startDate == null
? localizations.dateRangeStartLabel
: (endDate == null || startDate.year == endDate.year)
? localizations.formatShortMonthDay(startDate)
: localizations.formatShortDate(startDate);
}
/// Returns an locale-appropriate string to describe the end of a date range.
///
/// If `endDate` is null, then it defaults to 'End Date', otherwise if it
/// is in the same year as the `startDate` and the `currentDate` then it will
/// just use the short month day format (i.e. 'Jan 21'), otherwise it will
/// include the year (i.e. 'Jan 21, 2020').
String _formatRangeEndDate(MaterialLocalizations localizations, DateTime? startDate, DateTime? endDate, DateTime currentDate) {
return endDate == null
? localizations.dateRangeEndLabel
: (startDate != null && startDate.year == endDate.year && startDate.year == currentDate.year)
? localizations.formatShortMonthDay(endDate)
: localizations.formatShortDate(endDate);
}
/// A Material-style date range picker dialog.
///
/// It is used internally by [showDateRangePicker] or can be directly pushed
/// onto the [Navigator] stack to enable state restoration. See
/// [showDateRangePicker] for a state restoration app example.
///
/// See also:
///
/// * [showDateRangePicker], which is a way to display the date picker.
class DateRangePickerDialog extends StatefulWidget {
/// A Material-style date range picker dialog.
const DateRangePickerDialog({
super.key,
this.initialDateRange,
required this.firstDate,
required this.lastDate,
this.currentDate,
this.initialEntryMode = DatePickerEntryMode.calendar,
this.helpText,
this.cancelText,
this.confirmText,
this.saveText,
this.errorInvalidRangeText,
this.errorFormatText,
this.errorInvalidText,
this.fieldStartHintText,
this.fieldEndHintText,
this.fieldStartLabelText,
this.fieldEndLabelText,
this.keyboardType = TextInputType.datetime,
this.restorationId,
this.switchToInputEntryModeIcon,
this.switchToCalendarEntryModeIcon,
});
/// The date range that the date range picker starts with when it opens.
///
/// If an initial date range is provided, `initialDateRange.start`
/// and `initialDateRange.end` must both fall between or on [firstDate] and
/// [lastDate]. For all of these [DateTime] values, only their dates are
/// considered. Their time fields are ignored.
///
/// If [initialDateRange] is non-null, then it will be used as the initially
/// selected date range. If it is provided, `initialDateRange.start` must be
/// before or on `initialDateRange.end`.
final DateTimeRange? initialDateRange;
/// The earliest allowable date on the date range.
final DateTime firstDate;
/// The latest allowable date on the date range.
final DateTime lastDate;
/// The [currentDate] represents the current day (i.e. today).
///
/// This date will be highlighted in the day grid.
///
/// If `null`, the date of `DateTime.now()` will be used.
final DateTime? currentDate;
/// The initial date range picker entry mode.
///
/// The date range has two main modes: [DatePickerEntryMode.calendar] (a
/// scrollable calendar month grid) or [DatePickerEntryMode.input] (two text
/// input fields) mode.
///
/// It defaults to [DatePickerEntryMode.calendar] and must be non-null.
final DatePickerEntryMode initialEntryMode;
/// The label on the cancel button for the text input mode.
///
/// If null, the localized value of
/// [MaterialLocalizations.cancelButtonLabel] is used.
final String? cancelText;
/// The label on the "OK" button for the text input mode.
///
/// If null, the localized value of
/// [MaterialLocalizations.okButtonLabel] is used.
final String? confirmText;
/// The label on the save button for the fullscreen calendar mode.
///
/// If null, the localized value of
/// [MaterialLocalizations.saveButtonLabel] is used.
final String? saveText;
/// The label displayed at the top of the dialog.
///
/// If null, the localized value of
/// [MaterialLocalizations.dateRangePickerHelpText] is used.
final String? helpText;
/// The message used when the date range is invalid (e.g. start date is after
/// end date).
///
/// If null, the localized value of
/// [MaterialLocalizations.invalidDateRangeLabel] is used.
final String? errorInvalidRangeText;
/// The message used when an input text isn't in a proper date format.
///
/// If null, the localized value of
/// [MaterialLocalizations.invalidDateFormatLabel] is used.
final String? errorFormatText;
/// The message used when an input text isn't a selectable date.
///
/// If null, the localized value of
/// [MaterialLocalizations.dateOutOfRangeLabel] is used.
final String? errorInvalidText;
/// The text used to prompt the user when no text has been entered in the
/// start field.
///
/// If null, the localized value of
/// [MaterialLocalizations.dateHelpText] is used.
final String? fieldStartHintText;
/// The text used to prompt the user when no text has been entered in the
/// end field.
///
/// If null, the localized value of [MaterialLocalizations.dateHelpText] is
/// used.
final String? fieldEndHintText;
/// The label for the start date text input field.
///
/// If null, the localized value of [MaterialLocalizations.dateRangeStartLabel]
/// is used.
final String? fieldStartLabelText;
/// The label for the end date text input field.
///
/// If null, the localized value of [MaterialLocalizations.dateRangeEndLabel]
/// is used.
final String? fieldEndLabelText;
/// {@macro flutter.material.datePickerDialog}
final TextInputType keyboardType;
/// Restoration ID to save and restore the state of the [DateRangePickerDialog].
///
/// If it is non-null, the date range picker will persist and restore the
/// date range selected on the dialog.
///
/// The state of this widget is persisted in a [RestorationBucket] claimed
/// from the surrounding [RestorationScope] using the provided restoration ID.
///
/// See also:
///
/// * [RestorationManager], which explains how state restoration works in
/// Flutter.
final String? restorationId;
/// {@macro flutter.material.date_picker.switchToInputEntryModeIcon}
final Icon? switchToInputEntryModeIcon;
/// {@macro flutter.material.date_picker.switchToCalendarEntryModeIcon}
final Icon? switchToCalendarEntryModeIcon;
@override
State<DateRangePickerDialog> createState() => _DateRangePickerDialogState();
}
class _DateRangePickerDialogState extends State<DateRangePickerDialog> with RestorationMixin {
late final _RestorableDatePickerEntryMode _entryMode = _RestorableDatePickerEntryMode(widget.initialEntryMode);
late final RestorableDateTimeN _selectedStart = RestorableDateTimeN(widget.initialDateRange?.start);
late final RestorableDateTimeN _selectedEnd = RestorableDateTimeN(widget.initialDateRange?.end);
final RestorableBool _autoValidate = RestorableBool(false);
final GlobalKey _calendarPickerKey = GlobalKey();
final GlobalKey<_InputDateRangePickerState> _inputPickerKey = GlobalKey<_InputDateRangePickerState>();
@override
String? get restorationId => widget.restorationId;
@override
void restoreState(RestorationBucket? oldBucket, bool initialRestore) {
registerForRestoration(_entryMode, 'entry_mode');
registerForRestoration(_selectedStart, 'selected_start');
registerForRestoration(_selectedEnd, 'selected_end');
registerForRestoration(_autoValidate, 'autovalidate');
}
void _handleOk() {
if (_entryMode.value == DatePickerEntryMode.input || _entryMode.value == DatePickerEntryMode.inputOnly) {
final _InputDateRangePickerState picker = _inputPickerKey.currentState!;
if (!picker.validate()) {
setState(() {
_autoValidate.value = true;
});
return;
}
}
final DateTimeRange? selectedRange = _hasSelectedDateRange
? DateTimeRange(start: _selectedStart.value!, end: _selectedEnd.value!)
: null;
Navigator.pop(context, selectedRange);
}
void _handleCancel() {
Navigator.pop(context);
}
void _handleEntryModeToggle() {
setState(() {
switch (_entryMode.value) {
case DatePickerEntryMode.calendar:
_autoValidate.value = false;
_entryMode.value = DatePickerEntryMode.input;
case DatePickerEntryMode.input:
// Validate the range dates
if (_selectedStart.value != null &&
(_selectedStart.value!.isBefore(widget.firstDate) || _selectedStart.value!.isAfter(widget.lastDate))) {
_selectedStart.value = null;
// With no valid start date, having an end date makes no sense for the UI.
_selectedEnd.value = null;
}
if (_selectedEnd.value != null &&
(_selectedEnd.value!.isBefore(widget.firstDate) || _selectedEnd.value!.isAfter(widget.lastDate))) {
_selectedEnd.value = null;
}
// If invalid range (start after end), then just use the start date
if (_selectedStart.value != null && _selectedEnd.value != null && _selectedStart.value!.isAfter(_selectedEnd.value!)) {
_selectedEnd.value = null;
}
_entryMode.value = DatePickerEntryMode.calendar;
case DatePickerEntryMode.calendarOnly:
case DatePickerEntryMode.inputOnly:
assert(false, 'Can not change entry mode from $_entryMode');
}
});
}
void _handleStartDateChanged(DateTime? date) {
setState(() => _selectedStart.value = date);
}
void _handleEndDateChanged(DateTime? date) {
setState(() => _selectedEnd.value = date);
}
bool get _hasSelectedDateRange => _selectedStart.value != null && _selectedEnd.value != null;
@override
Widget build(BuildContext context) {
final ThemeData theme = Theme.of(context);
final bool useMaterial3 = theme.useMaterial3;
final Orientation orientation = MediaQuery.orientationOf(context);
final MaterialLocalizations localizations = MaterialLocalizations.of(context);
final DatePickerThemeData datePickerTheme = DatePickerTheme.of(context);
final DatePickerThemeData defaults = DatePickerTheme.defaults(context);
final Widget contents;
final Size size;
final double? elevation;
final Color? shadowColor;
final Color? surfaceTintColor;
final ShapeBorder? shape;
final EdgeInsets insetPadding;
final bool showEntryModeButton =
_entryMode.value == DatePickerEntryMode.calendar ||
_entryMode.value == DatePickerEntryMode.input;
switch (_entryMode.value) {
case DatePickerEntryMode.calendar:
case DatePickerEntryMode.calendarOnly:
contents = _CalendarRangePickerDialog(
key: _calendarPickerKey,
selectedStartDate: _selectedStart.value,
selectedEndDate: _selectedEnd.value,
firstDate: widget.firstDate,
lastDate: widget.lastDate,
currentDate: widget.currentDate,
onStartDateChanged: _handleStartDateChanged,
onEndDateChanged: _handleEndDateChanged,
onConfirm: _hasSelectedDateRange ? _handleOk : null,
onCancel: _handleCancel,
entryModeButton: showEntryModeButton
? IconButton(
icon: widget.switchToInputEntryModeIcon ?? Icon(useMaterial3 ? Icons.edit_outlined : Icons.edit),
padding: EdgeInsets.zero,
tooltip: localizations.inputDateModeButtonLabel,
onPressed: _handleEntryModeToggle,
)
: null,
confirmText: widget.saveText ?? (
useMaterial3
? localizations.saveButtonLabel
: localizations.saveButtonLabel.toUpperCase()
),
helpText: widget.helpText ?? (
useMaterial3
? localizations.dateRangePickerHelpText
: localizations.dateRangePickerHelpText.toUpperCase()
),
);
size = MediaQuery.sizeOf(context);
insetPadding = EdgeInsets.zero;
elevation = datePickerTheme.rangePickerElevation ?? defaults.rangePickerElevation!;
shadowColor = datePickerTheme.rangePickerShadowColor ?? defaults.rangePickerShadowColor!;
surfaceTintColor = datePickerTheme.rangePickerSurfaceTintColor ?? defaults.rangePickerSurfaceTintColor!;
shape = datePickerTheme.rangePickerShape ?? defaults.rangePickerShape;
case DatePickerEntryMode.input:
case DatePickerEntryMode.inputOnly:
contents = _InputDateRangePickerDialog(
selectedStartDate: _selectedStart.value,
selectedEndDate: _selectedEnd.value,
currentDate: widget.currentDate,
picker: Container(
padding: const EdgeInsets.symmetric(horizontal: 24),
height: orientation == Orientation.portrait
? _inputFormPortraitHeight
: _inputFormLandscapeHeight,
child: Column(
children: <Widget>[
const Spacer(),
_InputDateRangePicker(
key: _inputPickerKey,
initialStartDate: _selectedStart.value,
initialEndDate: _selectedEnd.value,
firstDate: widget.firstDate,
lastDate: widget.lastDate,
onStartDateChanged: _handleStartDateChanged,
onEndDateChanged: _handleEndDateChanged,
autofocus: true,
autovalidate: _autoValidate.value,
helpText: widget.helpText,
errorInvalidRangeText: widget.errorInvalidRangeText,
errorFormatText: widget.errorFormatText,
errorInvalidText: widget.errorInvalidText,
fieldStartHintText: widget.fieldStartHintText,
fieldEndHintText: widget.fieldEndHintText,
fieldStartLabelText: widget.fieldStartLabelText,
fieldEndLabelText: widget.fieldEndLabelText,
keyboardType: widget.keyboardType,
),
const Spacer(),
],
),
),
onConfirm: _handleOk,
onCancel: _handleCancel,
entryModeButton: showEntryModeButton
? IconButton(
icon: widget.switchToCalendarEntryModeIcon ?? const Icon(Icons.calendar_today),
padding: EdgeInsets.zero,
tooltip: localizations.calendarModeButtonLabel,
onPressed: _handleEntryModeToggle,
)
: null,
confirmText: widget.confirmText ?? localizations.okButtonLabel,
cancelText: widget.cancelText ?? (
useMaterial3
? localizations.cancelButtonLabel
: localizations.cancelButtonLabel.toUpperCase()
),
helpText: widget.helpText ?? (
useMaterial3
? localizations.dateRangePickerHelpText
: localizations.dateRangePickerHelpText.toUpperCase()
),
);
final DialogTheme dialogTheme = theme.dialogTheme;
size = orientation == Orientation.portrait
? (useMaterial3 ? _inputPortraitDialogSizeM3 : _inputPortraitDialogSizeM2)
: _inputRangeLandscapeDialogSize;
elevation = useMaterial3
? datePickerTheme.elevation ?? defaults.elevation!
: datePickerTheme.elevation ?? dialogTheme.elevation ?? 24;
shadowColor = datePickerTheme.shadowColor ?? defaults.shadowColor;
surfaceTintColor = datePickerTheme.surfaceTintColor ?? defaults.surfaceTintColor;
shape = useMaterial3
? datePickerTheme.shape ?? defaults.shape
: datePickerTheme.shape ?? dialogTheme.shape ?? defaults.shape;
insetPadding = const EdgeInsets.symmetric(horizontal: 16.0, vertical: 24.0);
}
return Dialog(
insetPadding: insetPadding,
backgroundColor: datePickerTheme.backgroundColor ?? defaults.backgroundColor,
elevation: elevation,
shadowColor: shadowColor,
surfaceTintColor: surfaceTintColor,
shape: shape,
clipBehavior: Clip.antiAlias,
child: AnimatedContainer(
width: size.width,
height: size.height,
duration: _dialogSizeAnimationDuration,
curve: Curves.easeIn,
child: MediaQuery.withClampedTextScaling(
maxScaleFactor: _kMaxTextScaleFactor,
child: Builder(builder: (BuildContext context) {
return contents;
}),
),
),
);
}
}
class _CalendarRangePickerDialog extends StatelessWidget {
const _CalendarRangePickerDialog({
super.key,
required this.selectedStartDate,
required this.selectedEndDate,
required this.firstDate,
required this.lastDate,
required this.currentDate,
required this.onStartDateChanged,
required this.onEndDateChanged,
required this.onConfirm,
required this.onCancel,
required this.confirmText,
required this.helpText,
this.entryModeButton,
});
final DateTime? selectedStartDate;
final DateTime? selectedEndDate;
final DateTime firstDate;
final DateTime lastDate;
final DateTime? currentDate;
final ValueChanged<DateTime> onStartDateChanged;
final ValueChanged<DateTime?> onEndDateChanged;
final VoidCallback? onConfirm;
final VoidCallback? onCancel;
final String confirmText;
final String helpText;
final Widget? entryModeButton;
@override
Widget build(BuildContext context) {
final ThemeData theme = Theme.of(context);
final bool useMaterial3 = theme.useMaterial3;
final MaterialLocalizations localizations = MaterialLocalizations.of(context);
final Orientation orientation = MediaQuery.orientationOf(context);
final DatePickerThemeData themeData = DatePickerTheme.of(context);
final DatePickerThemeData defaults = DatePickerTheme.defaults(context);
final Color? dialogBackground = themeData.rangePickerBackgroundColor ?? defaults.rangePickerBackgroundColor;
final Color? headerBackground = themeData.rangePickerHeaderBackgroundColor ?? defaults.rangePickerHeaderBackgroundColor;
final Color? headerForeground = themeData.rangePickerHeaderForegroundColor ?? defaults.rangePickerHeaderForegroundColor;
final Color? headerDisabledForeground = headerForeground?.withOpacity(0.38);
final TextStyle? headlineStyle = themeData.rangePickerHeaderHeadlineStyle ?? defaults.rangePickerHeaderHeadlineStyle;
final TextStyle? headlineHelpStyle = (themeData.rangePickerHeaderHelpStyle ?? defaults.rangePickerHeaderHelpStyle)?.apply(color: headerForeground);
final String startDateText = _formatRangeStartDate(localizations, selectedStartDate, selectedEndDate);
final String endDateText = _formatRangeEndDate(localizations, selectedStartDate, selectedEndDate, DateTime.now());
final TextStyle? startDateStyle = headlineStyle?.apply(
color: selectedStartDate != null ? headerForeground : headerDisabledForeground,
);
final TextStyle? endDateStyle = headlineStyle?.apply(
color: selectedEndDate != null ? headerForeground : headerDisabledForeground,
);
final ButtonStyle buttonStyle = TextButton.styleFrom(
foregroundColor: headerForeground,
disabledForegroundColor: headerDisabledForeground
);
final IconThemeData iconTheme = IconThemeData(color: headerForeground);
return SafeArea(
top: false,
left: false,
right: false,
child: Scaffold(
appBar: AppBar(
iconTheme: iconTheme,
actionsIconTheme: iconTheme,
elevation: useMaterial3 ? 0 : null,
scrolledUnderElevation: useMaterial3 ? 0 : null,
backgroundColor: useMaterial3 ? headerBackground : null,
leading: CloseButton(
onPressed: onCancel,
),
actions: <Widget>[
if (orientation == Orientation.landscape && entryModeButton != null)
entryModeButton!,
TextButton(
style: buttonStyle,
onPressed: onConfirm,
child: Text(confirmText),
),
const SizedBox(width: 8),
],
bottom: PreferredSize(
preferredSize: const Size(double.infinity, 64),
child: Row(children: <Widget>[
SizedBox(width: MediaQuery.sizeOf(context).width < 360 ? 42 : 72),
Expanded(
child: Semantics(
label: '$helpText $startDateText to $endDateText',
excludeSemantics: true,
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Text(helpText, style: headlineHelpStyle),
const SizedBox(height: 8),
Row(
children: <Widget>[
Text(
startDateText,
style: startDateStyle,
maxLines: 1,
overflow: TextOverflow.ellipsis,
),
Text(' – ', style: startDateStyle,
),
Flexible(
child: Text(
endDateText,
style: endDateStyle,
maxLines: 1,
overflow: TextOverflow.ellipsis,
),
),
],
),
const SizedBox(height: 16),
],
),
),
),
if (orientation == Orientation.portrait && entryModeButton != null)
Padding(
padding: const EdgeInsets.symmetric(horizontal: 8.0),
child: IconTheme(
data: iconTheme,
child: entryModeButton!,
),
),
]),
),
),
backgroundColor: dialogBackground,
body: _CalendarDateRangePicker(
initialStartDate: selectedStartDate,
initialEndDate: selectedEndDate,
firstDate: firstDate,
lastDate: lastDate,
currentDate: currentDate,
onStartDateChanged: onStartDateChanged,
onEndDateChanged: onEndDateChanged,
),
),
);
}
}
const Duration _monthScrollDuration = Duration(milliseconds: 200);
const double _monthItemHeaderHeight = 58.0;
const double _monthItemFooterHeight = 12.0;
const double _monthItemRowHeight = 42.0;
const double _monthItemSpaceBetweenRows = 8.0;
const double _horizontalPadding = 8.0;
const double _maxCalendarWidthLandscape = 384.0;
const double _maxCalendarWidthPortrait = 480.0;
/// Displays a scrollable calendar grid that allows a user to select a range
/// of dates.
class _CalendarDateRangePicker extends StatefulWidget {
/// Creates a scrollable calendar grid for picking date ranges.
_CalendarDateRangePicker({
DateTime? initialStartDate,
DateTime? initialEndDate,
required DateTime firstDate,
required DateTime lastDate,
DateTime? currentDate,
required this.onStartDateChanged,
required this.onEndDateChanged,
}) : initialStartDate = initialStartDate != null ? DateUtils.dateOnly(initialStartDate) : null,
initialEndDate = initialEndDate != null ? DateUtils.dateOnly(initialEndDate) : null,
firstDate = DateUtils.dateOnly(firstDate),
lastDate = DateUtils.dateOnly(lastDate),
currentDate = DateUtils.dateOnly(currentDate ?? DateTime.now()) {
assert(
this.initialStartDate == null || this.initialEndDate == null || !this.initialStartDate!.isAfter(initialEndDate!),
'initialStartDate must be on or before initialEndDate.',
);
assert(
!this.lastDate.isBefore(this.firstDate),
'firstDate must be on or before lastDate.',
);
}
/// The [DateTime] that represents the start of the initial date range selection.
final DateTime? initialStartDate;
/// The [DateTime] that represents the end of the initial date range selection.
final DateTime? initialEndDate;
/// The earliest allowable [DateTime] that the user can select.
final DateTime firstDate;
/// The latest allowable [DateTime] that the user can select.
final DateTime lastDate;
/// The [DateTime] representing today. It will be highlighted in the day grid.
final DateTime currentDate;
/// Called when the user changes the start date of the selected range.
final ValueChanged<DateTime>? onStartDateChanged;
/// Called when the user changes the end date of the selected range.
final ValueChanged<DateTime?>? onEndDateChanged;
@override
_CalendarDateRangePickerState createState() => _CalendarDateRangePickerState();
}
class _CalendarDateRangePickerState extends State<_CalendarDateRangePicker> {
final GlobalKey _scrollViewKey = GlobalKey();
DateTime? _startDate;
DateTime? _endDate;
int _initialMonthIndex = 0;
late ScrollController _controller;
late bool _showWeekBottomDivider;
@override
void initState() {
super.initState();
_controller = ScrollController();
_controller.addListener(_scrollListener);
_startDate = widget.initialStartDate;
_endDate = widget.initialEndDate;
// Calculate the index for the initially displayed month. This is needed to
// divide the list of months into two `SliverList`s.
final DateTime initialDate = widget.initialStartDate ?? widget.currentDate;
if (!initialDate.isBefore(widget.firstDate) &&
!initialDate.isAfter(widget.lastDate)) {
_initialMonthIndex = DateUtils.monthDelta(widget.firstDate, initialDate);
}
_showWeekBottomDivider = _initialMonthIndex != 0;
}
@override
void dispose() {
_controller.dispose();
super.dispose();
}
void _scrollListener() {
if (_controller.offset <= _controller.position.minScrollExtent) {
setState(() {
_showWeekBottomDivider = false;
});
} else if (!_showWeekBottomDivider) {
setState(() {
_showWeekBottomDivider = true;
});
}
}
int get _numberOfMonths => DateUtils.monthDelta(widget.firstDate, widget.lastDate) + 1;
void _vibrate() {
switch (Theme.of(context).platform) {
case TargetPlatform.android:
case TargetPlatform.fuchsia:
HapticFeedback.vibrate();
case TargetPlatform.iOS:
case TargetPlatform.linux:
case TargetPlatform.macOS:
case TargetPlatform.windows:
break;
}
}
// This updates the selected date range using this logic:
//
// * From the unselected state, selecting one date creates the start date.
// * If the next selection is before the start date, reset date range and
// set the start date to that selection.
// * If the next selection is on or after the start date, set the end date
// to that selection.
// * After both start and end dates are selected, any subsequent selection
// resets the date range and sets start date to that selection.
void _updateSelection(DateTime date) {
_vibrate();
setState(() {
if (_startDate != null && _endDate == null && !date.isBefore(_startDate!)) {
_endDate = date;
widget.onEndDateChanged?.call(_endDate);
} else {
_startDate = date;
widget.onStartDateChanged?.call(_startDate!);
if (_endDate != null) {
_endDate = null;
widget.onEndDateChanged?.call(_endDate);
}
}
});
}
Widget _buildMonthItem(BuildContext context, int index, bool beforeInitialMonth) {
final int monthIndex = beforeInitialMonth
? _initialMonthIndex - index - 1
: _initialMonthIndex + index;
final DateTime month = DateUtils.addMonthsToMonthDate(widget.firstDate, monthIndex);
return _MonthItem(
selectedDateStart: _startDate,
selectedDateEnd: _endDate,
currentDate: widget.currentDate,
firstDate: widget.firstDate,
lastDate: widget.lastDate,
displayedMonth: month,
onChanged: _updateSelection,
);
}
@override
Widget build(BuildContext context) {
const Key sliverAfterKey = Key('sliverAfterKey');
return Column(
children: <Widget>[
const _DayHeaders(),
if (_showWeekBottomDivider) const Divider(height: 0),
Expanded(
child: _CalendarKeyboardNavigator(
firstDate: widget.firstDate,
lastDate: widget.lastDate,
initialFocusedDay: _startDate ?? widget.initialStartDate ?? widget.currentDate,
// In order to prevent performance issues when displaying the
// correct initial month, 2 `SliverList`s are used to split the
// months. The first item in the second SliverList is the initial
// month to be displayed.
child: CustomScrollView(
key: _scrollViewKey,
controller: _controller,
center: sliverAfterKey,
slivers: <Widget>[
SliverList(
delegate: SliverChildBuilderDelegate(
(BuildContext context, int index) => _buildMonthItem(context, index, true),
childCount: _initialMonthIndex,
),
),
SliverList(
key: sliverAfterKey,
delegate: SliverChildBuilderDelegate(
(BuildContext context, int index) => _buildMonthItem(context, index, false),
childCount: _numberOfMonths - _initialMonthIndex,
),
),
],
),
),
),
],
);
}
}
class _CalendarKeyboardNavigator extends StatefulWidget {
const _CalendarKeyboardNavigator({
required this.child,
required this.firstDate,
required this.lastDate,
required this.initialFocusedDay,
});
final Widget child;
final DateTime firstDate;
final DateTime lastDate;
final DateTime initialFocusedDay;
@override
_CalendarKeyboardNavigatorState createState() => _CalendarKeyboardNavigatorState();
}
class _CalendarKeyboardNavigatorState extends State<_CalendarKeyboardNavigator> {
final Map<ShortcutActivator, Intent> _shortcutMap = const <ShortcutActivator, Intent>{
SingleActivator(LogicalKeyboardKey.arrowLeft): DirectionalFocusIntent(TraversalDirection.left),
SingleActivator(LogicalKeyboardKey.arrowRight): DirectionalFocusIntent(TraversalDirection.right),
SingleActivator(LogicalKeyboardKey.arrowDown): DirectionalFocusIntent(TraversalDirection.down),
SingleActivator(LogicalKeyboardKey.arrowUp): DirectionalFocusIntent(TraversalDirection.up),
};
late Map<Type, Action<Intent>> _actionMap;
late FocusNode _dayGridFocus;
TraversalDirection? _dayTraversalDirection;
DateTime? _focusedDay;
@override
void initState() {
super.initState();
_actionMap = <Type, Action<Intent>>{
NextFocusIntent: CallbackAction<NextFocusIntent>(onInvoke: _handleGridNextFocus),
PreviousFocusIntent: CallbackAction<PreviousFocusIntent>(onInvoke: _handleGridPreviousFocus),
DirectionalFocusIntent: CallbackAction<DirectionalFocusIntent>(onInvoke: _handleDirectionFocus),
};
_dayGridFocus = FocusNode(debugLabel: 'Day Grid');
}
@override
void dispose() {
_dayGridFocus.dispose();
super.dispose();
}
void _handleGridFocusChange(bool focused) {
setState(() {
if (focused) {
_focusedDay ??= widget.initialFocusedDay;
}
});
}
/// Move focus to the next element after the day grid.
void _handleGridNextFocus(NextFocusIntent intent) {
_dayGridFocus.requestFocus();
_dayGridFocus.nextFocus();
}
/// Move focus to the previous element before the day grid.
void _handleGridPreviousFocus(PreviousFocusIntent intent) {
_dayGridFocus.requestFocus();
_dayGridFocus.previousFocus();
}
/// Move the internal focus date in the direction of the given intent.
///
/// This will attempt to move the focused day to the next selectable day in
/// the given direction. If the new date is not in the current month, then
/// the page view will be scrolled to show the new date's month.
///
/// For horizontal directions, it will move forward or backward a day (depending
/// on the current [TextDirection]). For vertical directions it will move up and
/// down a week at a time.
void _handleDirectionFocus(DirectionalFocusIntent intent) {
assert(_focusedDay != null);
setState(() {
final DateTime? nextDate = _nextDateInDirection(_focusedDay!, intent.direction);
if (nextDate != null) {
_focusedDay = nextDate;
_dayTraversalDirection = intent.direction;
}
});
}
static const Map<TraversalDirection, int> _directionOffset = <TraversalDirection, int>{
TraversalDirection.up: -DateTime.daysPerWeek,
TraversalDirection.right: 1,
TraversalDirection.down: DateTime.daysPerWeek,
TraversalDirection.left: -1,
};
int _dayDirectionOffset(TraversalDirection traversalDirection, TextDirection textDirection) {
// Swap left and right if the text direction if RTL
if (textDirection == TextDirection.rtl) {
if (traversalDirection == TraversalDirection.left) {
traversalDirection = TraversalDirection.right;
} else if (traversalDirection == TraversalDirection.right) {
traversalDirection = TraversalDirection.left;
}
}
return _directionOffset[traversalDirection]!;
}
DateTime? _nextDateInDirection(DateTime date, TraversalDirection direction) {
final TextDirection textDirection = Directionality.of(context);
final DateTime nextDate = DateUtils.addDaysToDate(date, _dayDirectionOffset(direction, textDirection));
if (!nextDate.isBefore(widget.firstDate) && !nextDate.isAfter(widget.lastDate)) {
return nextDate;
}
return null;
}
@override
Widget build(BuildContext context) {
return FocusableActionDetector(
shortcuts: _shortcutMap,
actions: _actionMap,
focusNode: _dayGridFocus,
onFocusChange: _handleGridFocusChange,
child: _FocusedDate(
date: _dayGridFocus.hasFocus ? _focusedDay : null,
scrollDirection: _dayGridFocus.hasFocus ? _dayTraversalDirection : null,
child: widget.child,
),
);
}
}
/// InheritedWidget indicating what the current focused date is for its children.
///
/// This is used by the [_MonthPicker] to let its children [_DayPicker]s know
/// what the currently focused date (if any) should be.
class _FocusedDate extends InheritedWidget {
const _FocusedDate({
required super.child,
this.date,
this.scrollDirection,
});
final DateTime? date;
final TraversalDirection? scrollDirection;
@override
bool updateShouldNotify(_FocusedDate oldWidget) {
return !DateUtils.isSameDay(date, oldWidget.date) || scrollDirection != oldWidget.scrollDirection;
}
static _FocusedDate? maybeOf(BuildContext context) {
return context.dependOnInheritedWidgetOfExactType<_FocusedDate>();
}
}
class _DayHeaders extends StatelessWidget {
const _DayHeaders();
/// Builds widgets showing abbreviated days of week. The first widget in the
/// returned list corresponds to the first day of week for the current locale.
///
/// Examples:
///
/// ┌ Sunday is the first day of week in the US (en_US)
/// |
/// S M T W T F S ← the returned list contains these widgets
/// _ _ _ _ _ 1 2
/// 3 4 5 6 7 8 9
///
/// ┌ But it's Monday in the UK (en_GB)
/// |
/// M T W T F S S ← the returned list contains these widgets
/// _ _ _ _ 1 2 3
/// 4 5 6 7 8 9 10
///
List<Widget> _getDayHeaders(TextStyle headerStyle, MaterialLocalizations localizations) {
final List<Widget> result = <Widget>[];
for (int i = localizations.firstDayOfWeekIndex; true; i = (i + 1) % 7) {
final String weekday = localizations.narrowWeekdays[i];
result.add(ExcludeSemantics(
child: Center(child: Text(weekday, style: headerStyle)),
));
if (i == (localizations.firstDayOfWeekIndex - 1) % 7) {
break;
}
}
return result;
}
@override
Widget build(BuildContext context) {
final ThemeData themeData = Theme.of(context);
final ColorScheme colorScheme = themeData.colorScheme;
final TextStyle textStyle = themeData.textTheme.titleSmall!.apply(color: colorScheme.onSurface);
final MaterialLocalizations localizations = MaterialLocalizations.of(context);
final List<Widget> labels = _getDayHeaders(textStyle, localizations);
// Add leading and trailing containers for edges of the custom grid layout.
labels.insert(0, Container());
labels.add(Container());
return Container(
constraints: BoxConstraints(
maxWidth: MediaQuery.orientationOf(context) == Orientation.landscape
? _maxCalendarWidthLandscape
: _maxCalendarWidthPortrait,
maxHeight: _monthItemRowHeight,
),
child: GridView.custom(
shrinkWrap: true,
gridDelegate: _monthItemGridDelegate,
childrenDelegate: SliverChildListDelegate(
labels,
addRepaintBoundaries: false,
),
),
);
}
}
class _MonthItemGridDelegate extends SliverGridDelegate {
const _MonthItemGridDelegate();
@override
SliverGridLayout getLayout(SliverConstraints constraints) {
final double tileWidth = (constraints.crossAxisExtent - 2 * _horizontalPadding) / DateTime.daysPerWeek;
return _MonthSliverGridLayout(
crossAxisCount: DateTime.daysPerWeek + 2,
dayChildWidth: tileWidth,
edgeChildWidth: _horizontalPadding,
reverseCrossAxis: axisDirectionIsReversed(constraints.crossAxisDirection),
);
}
@override
bool shouldRelayout(_MonthItemGridDelegate oldDelegate) => false;
}
const _MonthItemGridDelegate _monthItemGridDelegate = _MonthItemGridDelegate();
class _MonthSliverGridLayout extends SliverGridLayout {
/// Creates a layout that uses equally sized and spaced tiles for each day of
/// the week and an additional edge tile for padding at the start and end of
/// each row.
///
/// This is necessary to facilitate the painting of the range highlight
/// correctly.
const _MonthSliverGridLayout({
required this.crossAxisCount,
required this.dayChildWidth,
required this.edgeChildWidth,
required this.reverseCrossAxis,
}) : assert(crossAxisCount > 0),
assert(dayChildWidth >= 0),
assert(edgeChildWidth >= 0);
/// The number of children in the cross axis.
final int crossAxisCount;
/// The width in logical pixels of the day child widgets.
final double dayChildWidth;
/// The width in logical pixels of the edge child widgets.
final double edgeChildWidth;
/// Whether the children should be placed in the opposite order of increasing
/// coordinates in the cross axis.
///
/// For example, if the cross axis is horizontal, the children are placed from
/// left to right when [reverseCrossAxis] is false and from right to left when
/// [reverseCrossAxis] is true.
///
/// Typically set to the return value of [axisDirectionIsReversed] applied to
/// the [SliverConstraints.crossAxisDirection].
final bool reverseCrossAxis;
/// The number of logical pixels from the leading edge of one row to the
/// leading edge of the next row.
double get _rowHeight {
return _monthItemRowHeight + _monthItemSpaceBetweenRows;
}
/// The height in logical pixels of the children widgets.
double get _childHeight {
return _monthItemRowHeight;
}
@override
int getMinChildIndexForScrollOffset(double scrollOffset) {
return crossAxisCount * (scrollOffset ~/ _rowHeight);
}
@override
int getMaxChildIndexForScrollOffset(double scrollOffset) {
final int mainAxisCount = (scrollOffset / _rowHeight).ceil();
return math.max(0, crossAxisCount * mainAxisCount - 1);
}
double _getCrossAxisOffset(double crossAxisStart, bool isPadding) {
if (reverseCrossAxis) {
return
((crossAxisCount - 2) * dayChildWidth + 2 * edgeChildWidth) -
crossAxisStart -
(isPadding ? edgeChildWidth : dayChildWidth);
}
return crossAxisStart;
}
@override
SliverGridGeometry getGeometryForChildIndex(int index) {
final int adjustedIndex = index % crossAxisCount;
final bool isEdge = adjustedIndex == 0 || adjustedIndex == crossAxisCount - 1;
final double crossAxisStart = math.max(0, (adjustedIndex - 1) * dayChildWidth + edgeChildWidth);
return SliverGridGeometry(
scrollOffset: (index ~/ crossAxisCount) * _rowHeight,
crossAxisOffset: _getCrossAxisOffset(crossAxisStart, isEdge),
mainAxisExtent: _childHeight,
crossAxisExtent: isEdge ? edgeChildWidth : dayChildWidth,
);
}
@override
double computeMaxScrollOffset(int childCount) {
assert(childCount >= 0);
final int mainAxisCount = ((childCount - 1) ~/ crossAxisCount) + 1;
final double mainAxisSpacing = _rowHeight - _childHeight;
return _rowHeight * mainAxisCount - mainAxisSpacing;
}
}
/// Displays the days of a given month and allows choosing a date range.
///
/// The days are arranged in a rectangular grid with one column for each day of
/// the week.
class _MonthItem extends StatefulWidget {
/// Creates a month item.
_MonthItem({
required this.selectedDateStart,
required this.selectedDateEnd,
required this.currentDate,
required this.onChanged,
required this.firstDate,
required this.lastDate,
required this.displayedMonth,
}) : assert(!firstDate.isAfter(lastDate)),
assert(selectedDateStart == null || !selectedDateStart.isBefore(firstDate)),
assert(selectedDateEnd == null || !selectedDateEnd.isBefore(firstDate)),
assert(selectedDateStart == null || !selectedDateStart.isAfter(lastDate)),
assert(selectedDateEnd == null || !selectedDateEnd.isAfter(lastDate)),
assert(selectedDateStart == null || selectedDateEnd == null || !selectedDateStart.isAfter(selectedDateEnd));
/// The currently selected start date.
///
/// This date is highlighted in the picker.
final DateTime? selectedDateStart;
/// The currently selected end date.
///
/// This date is highlighted in the picker.
final DateTime? selectedDateEnd;
/// The current date at the time the picker is displayed.
final DateTime currentDate;
/// Called when the user picks a day.
final ValueChanged<DateTime> onChanged;
/// The earliest date the user is permitted to pick.
final DateTime firstDate;
/// The latest date the user is permitted to pick.
final DateTime lastDate;
/// The month whose days are displayed by this picker.
final DateTime displayedMonth;
@override
_MonthItemState createState() => _MonthItemState();
}
class _MonthItemState extends State<_MonthItem> {
/// List of [FocusNode]s, one for each day of the month.
late List<FocusNode> _dayFocusNodes;
@override
void initState() {
super.initState();
final int daysInMonth = DateUtils.getDaysInMonth(widget.displayedMonth.year, widget.displayedMonth.month);
_dayFocusNodes = List<FocusNode>.generate(
daysInMonth,
(int index) => FocusNode(skipTraversal: true, debugLabel: 'Day ${index + 1}'),
);
}
@override
void didChangeDependencies() {
super.didChangeDependencies();
// Check to see if the focused date is in this month, if so focus it.
final DateTime? focusedDate = _FocusedDate.maybeOf(context)?.date;
if (focusedDate != null && DateUtils.isSameMonth(widget.displayedMonth, focusedDate)) {
_dayFocusNodes[focusedDate.day - 1].requestFocus();
}
}
@override
void dispose() {
for (final FocusNode node in _dayFocusNodes) {
node.dispose();
}
super.dispose();
}
Color _highlightColor(BuildContext context) {
return DatePickerTheme.of(context).rangeSelectionBackgroundColor
?? DatePickerTheme.defaults(context).rangeSelectionBackgroundColor!;
}
void _dayFocusChanged(bool focused) {
if (focused) {
final TraversalDirection? focusDirection = _FocusedDate.maybeOf(context)?.scrollDirection;
if (focusDirection != null) {
ScrollPositionAlignmentPolicy policy = ScrollPositionAlignmentPolicy.explicit;
switch (focusDirection) {
case TraversalDirection.up:
case TraversalDirection.left:
policy = ScrollPositionAlignmentPolicy.keepVisibleAtStart;
case TraversalDirection.right:
case TraversalDirection.down:
policy = ScrollPositionAlignmentPolicy.keepVisibleAtEnd;
}
Scrollable.ensureVisible(primaryFocus!.context!,
duration: _monthScrollDuration,
alignmentPolicy: policy,
);
}
}
}
Widget _buildDayItem(BuildContext context, DateTime dayToBuild, int firstDayOffset, int daysInMonth) {
final ThemeData theme = Theme.of(context);
final ColorScheme colorScheme = theme.colorScheme;
final TextTheme textTheme = theme.textTheme;
final MaterialLocalizations localizations = MaterialLocalizations.of(context);
final DatePickerThemeData datePickerTheme = DatePickerTheme.of(context);
final DatePickerThemeData defaults = DatePickerTheme.defaults(context);
final TextDirection textDirection = Directionality.of(context);
final Color highlightColor = _highlightColor(context);
final int day = dayToBuild.day;
final bool isDisabled = dayToBuild.isAfter(widget.lastDate) || dayToBuild.isBefore(widget.firstDate);
BoxDecoration? decoration;
TextStyle? itemStyle = textTheme.bodyMedium;
final bool isRangeSelected = widget.selectedDateStart != null && widget.selectedDateEnd != null;
final bool isSelectedDayStart = widget.selectedDateStart != null && dayToBuild.isAtSameMomentAs(widget.selectedDateStart!);
final bool isSelectedDayEnd = widget.selectedDateEnd != null && dayToBuild.isAtSameMomentAs(widget.selectedDateEnd!);
final bool isInRange = isRangeSelected &&
dayToBuild.isAfter(widget.selectedDateStart!) &&
dayToBuild.isBefore(widget.selectedDateEnd!);
T? effectiveValue<T>(T? Function(DatePickerThemeData? theme) getProperty) {
return getProperty(datePickerTheme) ?? getProperty(defaults);
}
T? resolve<T>(MaterialStateProperty<T>? Function(DatePickerThemeData? theme) getProperty, Set<MaterialState> states) {
return effectiveValue(
(DatePickerThemeData? theme) {
return getProperty(theme)?.resolve(states);
},
);
}
final Set<MaterialState> states = <MaterialState>{
if (isDisabled) MaterialState.disabled,
if (isSelectedDayStart || isSelectedDayEnd) MaterialState.selected,
};
final Color? dayForegroundColor = resolve<Color?>((DatePickerThemeData? theme) => theme?.dayForegroundColor, states);
final Color? dayBackgroundColor = resolve<Color?>((DatePickerThemeData? theme) => theme?.dayBackgroundColor, states);
final MaterialStateProperty<Color?> dayOverlayColor = MaterialStateProperty.resolveWith<Color?>(
(Set<MaterialState> states) => effectiveValue(
(DatePickerThemeData? theme) =>
isInRange
? theme?.rangeSelectionOverlayColor?.resolve(states)
: theme?.dayOverlayColor?.resolve(states),
)
);
_HighlightPainter? highlightPainter;
if (isSelectedDayStart || isSelectedDayEnd) {
// The selected start and end dates gets a circle background
// highlight, and a contrasting text color.
itemStyle = textTheme.bodyMedium?.apply(color: dayForegroundColor);
decoration = BoxDecoration(
color: dayBackgroundColor,
shape: BoxShape.circle,
);
if (isRangeSelected && widget.selectedDateStart != widget.selectedDateEnd) {
final _HighlightPainterStyle style = isSelectedDayStart
? _HighlightPainterStyle.highlightTrailing
: _HighlightPainterStyle.highlightLeading;
highlightPainter = _HighlightPainter(
color: highlightColor,
style: style,
textDirection: textDirection,
);
}
} else if (isInRange) {
// The days within the range get a light background highlight.
highlightPainter = _HighlightPainter(
color: highlightColor,
style: _HighlightPainterStyle.highlightAll,
textDirection: textDirection,
);
} else if (isDisabled) {
itemStyle = textTheme.bodyMedium?.apply(color: colorScheme.onSurface.withOpacity(0.38));
} else if (DateUtils.isSameDay(widget.currentDate, dayToBuild)) {
// The current day gets a different text color and a circle stroke
// border.
itemStyle = textTheme.bodyMedium?.apply(color: colorScheme.primary);
decoration = BoxDecoration(
border: Border.all(color: colorScheme.primary),
shape: BoxShape.circle,
);
}
// We want the day of month to be spoken first irrespective of the
// locale-specific preferences or TextDirection. This is because
// an accessibility user is more likely to be interested in the
// day of month before the rest of the date, as they are looking
// for the day of month. To do that we prepend day of month to the
// formatted full date.
final String semanticLabelSuffix = DateUtils.isSameDay(widget.currentDate, dayToBuild) ? ', ${localizations.currentDateLabel}' : '';
String semanticLabel = '${localizations.formatDecimal(day)}, ${localizations.formatFullDate(dayToBuild)}$semanticLabelSuffix';
if (isSelectedDayStart) {
semanticLabel = localizations.dateRangeStartDateSemanticLabel(semanticLabel);
} else if (isSelectedDayEnd) {
semanticLabel = localizations.dateRangeEndDateSemanticLabel(semanticLabel);
}
Widget dayWidget = Container(
decoration: decoration,
child: Center(
child: Semantics(
label: semanticLabel,
selected: isSelectedDayStart || isSelectedDayEnd,
child: ExcludeSemantics(
child: Text(localizations.formatDecimal(day), style: itemStyle),
),
),
),
);
if (highlightPainter != null) {
dayWidget = CustomPaint(
painter: highlightPainter,
child: dayWidget,
);
}
if (!isDisabled) {
dayWidget = InkResponse(
focusNode: _dayFocusNodes[day - 1],
onTap: () => widget.onChanged(dayToBuild),
radius: _monthItemRowHeight / 2 + 4,
statesController: MaterialStatesController(states),
overlayColor: dayOverlayColor,
onFocusChange: _dayFocusChanged,
child: dayWidget,
);
}
return dayWidget;
}
Widget _buildEdgeContainer(BuildContext context, bool isHighlighted) {
return Container(color: isHighlighted ? _highlightColor(context) : null);
}
@override
Widget build(BuildContext context) {
final ThemeData themeData = Theme.of(context);
final TextTheme textTheme = themeData.textTheme;
final MaterialLocalizations localizations = MaterialLocalizations.of(context);
final int year = widget.displayedMonth.year;
final int month = widget.displayedMonth.month;
final int daysInMonth = DateUtils.getDaysInMonth(year, month);
final int dayOffset = DateUtils.firstDayOffset(year, month, localizations);
final int weeks = ((daysInMonth + dayOffset) / DateTime.daysPerWeek).ceil();
final double gridHeight = weeks * _monthItemRowHeight + (weeks - 1) * _monthItemSpaceBetweenRows;
final List<Widget> dayItems = <Widget>[];
for (int i = 0; true; i += 1) {
// 1-based day of month, e.g. 1-31 for January, and 1-29 for February on
// a leap year.
final int day = i - dayOffset + 1;
if (day > daysInMonth) {
break;
}
if (day < 1) {
dayItems.add(Container());
} else {
final DateTime dayToBuild = DateTime(year, month, day);
final Widget dayItem = _buildDayItem(
context,
dayToBuild,
dayOffset,
daysInMonth,
);
dayItems.add(dayItem);
}
}
// Add the leading/trailing edge containers to each week in order to
// correctly extend the range highlight.
final List<Widget> paddedDayItems = <Widget>[];
for (int i = 0; i < weeks; i++) {
final int start = i * DateTime.daysPerWeek;
final int end = math.min(
start + DateTime.daysPerWeek,
dayItems.length,
);
final List<Widget> weekList = dayItems.sublist(start, end);
final DateTime dateAfterLeadingPadding = DateTime(year, month, start - dayOffset + 1);
// Only color the edge container if it is after the start date and
// on/before the end date.
final bool isLeadingInRange =
!(dayOffset > 0 && i == 0) &&
widget.selectedDateStart != null &&
widget.selectedDateEnd != null &&
dateAfterLeadingPadding.isAfter(widget.selectedDateStart!) &&
!dateAfterLeadingPadding.isAfter(widget.selectedDateEnd!);
weekList.insert(0, _buildEdgeContainer(context, isLeadingInRange));
// Only add a trailing edge container if it is for a full week and not a
// partial week.
if (end < dayItems.length || (end == dayItems.length && dayItems.length % DateTime.daysPerWeek == 0)) {
final DateTime dateBeforeTrailingPadding =
DateTime(year, month, end - dayOffset);
// Only color the edge container if it is on/after the start date and
// before the end date.
final bool isTrailingInRange =
widget.selectedDateStart != null &&
widget.selectedDateEnd != null &&
!dateBeforeTrailingPadding.isBefore(widget.selectedDateStart!) &&
dateBeforeTrailingPadding.isBefore(widget.selectedDateEnd!);
weekList.add(_buildEdgeContainer(context, isTrailingInRange));
}
paddedDayItems.addAll(weekList);
}
final double maxWidth = MediaQuery.orientationOf(context) == Orientation.landscape
? _maxCalendarWidthLandscape
: _maxCalendarWidthPortrait;
return Column(
children: <Widget>[
Container(
constraints: BoxConstraints(maxWidth: maxWidth),
height: _monthItemHeaderHeight,
padding: const EdgeInsets.symmetric(horizontal: 16),
alignment: AlignmentDirectional.centerStart,
child: ExcludeSemantics(
child: Text(
localizations.formatMonthYear(widget.displayedMonth),
style: textTheme.bodyMedium!.apply(color: themeData.colorScheme.onSurface),
),
),
),
Container(
constraints: BoxConstraints(
maxWidth: maxWidth,
maxHeight: gridHeight,
),
child: GridView.custom(
physics: const NeverScrollableScrollPhysics(),
gridDelegate: _monthItemGridDelegate,
childrenDelegate: SliverChildListDelegate(
paddedDayItems,
addRepaintBoundaries: false,
),
),
),
const SizedBox(height: _monthItemFooterHeight),
],
);
}
}
/// Determines which style to use to paint the highlight.
enum _HighlightPainterStyle {
/// Paints nothing.
none,
/// Paints a rectangle that occupies the leading half of the space.
highlightLeading,
/// Paints a rectangle that occupies the trailing half of the space.
highlightTrailing,
/// Paints a rectangle that occupies all available space.
highlightAll,
}
/// This custom painter will add a background highlight to its child.
///
/// This highlight will be drawn depending on the [style], [color], and
/// [textDirection] supplied. It will either paint a rectangle on the
/// left/right, a full rectangle, or nothing at all. This logic is determined by
/// a combination of the [style] and [textDirection].
class _HighlightPainter extends CustomPainter {
_HighlightPainter({
required this.color,
this.style = _HighlightPainterStyle.none,
this.textDirection,
});
final Color color;
final _HighlightPainterStyle style;
final TextDirection? textDirection;
@override
void paint(Canvas canvas, Size size) {
if (style == _HighlightPainterStyle.none) {
return;
}
final Paint paint = Paint()
..color = color
..style = PaintingStyle.fill;
final Rect rectLeft = Rect.fromLTWH(0, 0, size.width / 2, size.height);
final Rect rectRight = Rect.fromLTWH(size.width / 2, 0, size.width / 2, size.height);
switch (style) {
case _HighlightPainterStyle.highlightTrailing:
canvas.drawRect(
textDirection == TextDirection.ltr ? rectRight : rectLeft,
paint,
);
case _HighlightPainterStyle.highlightLeading:
canvas.drawRect(
textDirection == TextDirection.ltr ? rectLeft : rectRight,
paint,
);
case _HighlightPainterStyle.highlightAll:
canvas.drawRect(
Rect.fromLTWH(0, 0, size.width, size.height),
paint,
);
case _HighlightPainterStyle.none:
break;
}
}
@override
bool shouldRepaint(CustomPainter oldDelegate) => false;
}
class _InputDateRangePickerDialog extends StatelessWidget {
const _InputDateRangePickerDialog({
required this.selectedStartDate,
required this.selectedEndDate,
required this.currentDate,
required this.picker,
required this.onConfirm,
required this.onCancel,
required this.confirmText,
required this.cancelText,
required this.helpText,
required this.entryModeButton,
});
final DateTime? selectedStartDate;
final DateTime? selectedEndDate;
final DateTime? currentDate;
final Widget picker;
final VoidCallback onConfirm;
final VoidCallback onCancel;
final String? confirmText;
final String? cancelText;
final String? helpText;
final Widget? entryModeButton;
String _formatDateRange(BuildContext context, DateTime? start, DateTime? end, DateTime now) {
final MaterialLocalizations localizations = MaterialLocalizations.of(context);
final String startText = _formatRangeStartDate(localizations, start, end);
final String endText = _formatRangeEndDate(localizations, start, end, now);
if (start == null || end == null) {
return localizations.unspecifiedDateRange;
}
if (Directionality.of(context) == TextDirection.ltr) {
return '$startText – $endText';
} else {
return '$endText – $startText';
}
}
@override
Widget build(BuildContext context) {
final bool useMaterial3 = Theme.of(context).useMaterial3;
final MaterialLocalizations localizations = MaterialLocalizations.of(context);
final Orientation orientation = MediaQuery.orientationOf(context);
final DatePickerThemeData datePickerTheme = DatePickerTheme.of(context);
final DatePickerThemeData defaults = DatePickerTheme.defaults(context);
// There's no M3 spec for a landscape layout input (not calendar)
// date range picker. To ensure that the date range displayed in the
// input date range picker's header fits in landscape mode, we override
// the M3 default here.
TextStyle? headlineStyle = (orientation == Orientation.portrait)
? datePickerTheme.headerHeadlineStyle ?? defaults.headerHeadlineStyle
: Theme.of(context).textTheme.headlineSmall;
final Color? headerForegroundColor = datePickerTheme.headerForegroundColor ?? defaults.headerForegroundColor;
headlineStyle = headlineStyle?.copyWith(color: headerForegroundColor);
final String dateText = _formatDateRange(context, selectedStartDate, selectedEndDate, currentDate!);
final String semanticDateText = selectedStartDate != null && selectedEndDate != null
? '${localizations.formatMediumDate(selectedStartDate!)} – ${localizations.formatMediumDate(selectedEndDate!)}'
: '';
final Widget header = _DatePickerHeader(
helpText: helpText ?? (
useMaterial3
? localizations.dateRangePickerHelpText
: localizations.dateRangePickerHelpText.toUpperCase()
),
titleText: dateText,
titleSemanticsLabel: semanticDateText,
titleStyle: headlineStyle,
orientation: orientation,
isShort: orientation == Orientation.landscape,
entryModeButton: entryModeButton,
);
final Widget actions = Container(
alignment: AlignmentDirectional.centerEnd,
constraints: const BoxConstraints(minHeight: 52.0),
padding: const EdgeInsets.symmetric(horizontal: 8),
child: OverflowBar(
spacing: 8,
children: <Widget>[
TextButton(
onPressed: onCancel,
child: Text(cancelText ?? (
useMaterial3
? localizations.cancelButtonLabel
: localizations.cancelButtonLabel.toUpperCase()
)),
),
TextButton(
onPressed: onConfirm,
child: Text(confirmText ?? localizations.okButtonLabel),
),
],
),
);
switch (orientation) {
case Orientation.portrait:
return Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
header,
Expanded(child: picker),
actions,
],
);
case Orientation.landscape:
return Row(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
header,
Flexible(
child: Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
Expanded(child: picker),
actions,
],
),
),
],
);
}
}
}
/// Provides a pair of text fields that allow the user to enter the start and
/// end dates that represent a range of dates.
class _InputDateRangePicker extends StatefulWidget {
/// Creates a row with two text fields configured to accept the start and end dates
/// of a date range.
_InputDateRangePicker({
super.key,
DateTime? initialStartDate,
DateTime? initialEndDate,
required DateTime firstDate,
required DateTime lastDate,
required this.onStartDateChanged,
required this.onEndDateChanged,
this.helpText,
this.errorFormatText,
this.errorInvalidText,
this.errorInvalidRangeText,
this.fieldStartHintText,
this.fieldEndHintText,
this.fieldStartLabelText,
this.fieldEndLabelText,
this.autofocus = false,
this.autovalidate = false,
this.keyboardType = TextInputType.datetime,
}) : initialStartDate = initialStartDate == null ? null : DateUtils.dateOnly(initialStartDate),
initialEndDate = initialEndDate == null ? null : DateUtils.dateOnly(initialEndDate),
firstDate = DateUtils.dateOnly(firstDate),
lastDate = DateUtils.dateOnly(lastDate);
/// The [DateTime] that represents the start of the initial date range selection.
final DateTime? initialStartDate;
/// The [DateTime] that represents the end of the initial date range selection.
final DateTime? initialEndDate;
/// The earliest allowable [DateTime] that the user can select.
final DateTime firstDate;
/// The latest allowable [DateTime] that the user can select.
final DateTime lastDate;
/// Called when the user changes the start date of the selected range.
final ValueChanged<DateTime?>? onStartDateChanged;
/// Called when the user changes the end date of the selected range.
final ValueChanged<DateTime?>? onEndDateChanged;
/// The text that is displayed at the top of the header.
///
/// This is used to indicate to the user what they are selecting a date for.
final String? helpText;
/// Error text used to indicate the text in a field is not a valid date.
final String? errorFormatText;
/// Error text used to indicate the date in a field is not in the valid range
/// of [firstDate] - [lastDate].
final String? errorInvalidText;
/// Error text used to indicate the dates given don't form a valid date
/// range (i.e. the start date is after the end date).
final String? errorInvalidRangeText;
/// Hint text shown when the start date field is empty.
final String? fieldStartHintText;
/// Hint text shown when the end date field is empty.
final String? fieldEndHintText;
/// Label used for the start date field.
final String? fieldStartLabelText;
/// Label used for the end date field.
final String? fieldEndLabelText;
/// {@macro flutter.widgets.editableText.autofocus}
final bool autofocus;
/// If true, the date fields will validate and update their error text
/// immediately after every change. Otherwise, you must call
/// [_InputDateRangePickerState.validate] to validate.
final bool autovalidate;
/// {@macro flutter.material.datePickerDialog}
final TextInputType keyboardType;
@override
_InputDateRangePickerState createState() => _InputDateRangePickerState();
}
/// The current state of an [_InputDateRangePicker]. Can be used to
/// [validate] the date field entries.
class _InputDateRangePickerState extends State<_InputDateRangePicker> {
late String _startInputText;
late String _endInputText;
DateTime? _startDate;
DateTime? _endDate;
late TextEditingController _startController;
late TextEditingController _endController;
String? _startErrorText;
String? _endErrorText;
bool _autoSelected = false;
@override
void initState() {
super.initState();
_startDate = widget.initialStartDate;
_startController = TextEditingController();
_endDate = widget.initialEndDate;
_endController = TextEditingController();
}
@override
void dispose() {
_startController.dispose();
_endController.dispose();
super.dispose();
}
@override
void didChangeDependencies() {
super.didChangeDependencies();
final MaterialLocalizations localizations = MaterialLocalizations.of(context);
if (_startDate != null) {
_startInputText = localizations.formatCompactDate(_startDate!);
final bool selectText = widget.autofocus && !_autoSelected;
_updateController(_startController, _startInputText, selectText);
_autoSelected = selectText;
}
if (_endDate != null) {
_endInputText = localizations.formatCompactDate(_endDate!);
_updateController(_endController, _endInputText, false);
}
}
/// Validates that the text in the start and end fields represent a valid
/// date range.
///
/// Will return true if the range is valid. If not, it will
/// return false and display an appropriate error message under one of the
/// text fields.
bool validate() {
String? startError = _validateDate(_startDate);
final String? endError = _validateDate(_endDate);
if (startError == null && endError == null) {
if (_startDate!.isAfter(_endDate!)) {
startError = widget.errorInvalidRangeText ?? MaterialLocalizations.of(context).invalidDateRangeLabel;
}
}
setState(() {
_startErrorText = startError;
_endErrorText = endError;
});
return startError == null && endError == null;
}
DateTime? _parseDate(String? text) {
final MaterialLocalizations localizations = MaterialLocalizations.of(context);
return localizations.parseCompactDate(text);
}
String? _validateDate(DateTime? date) {
if (date == null) {
return widget.errorFormatText ?? MaterialLocalizations.of(context).invalidDateFormatLabel;
} else if (date.isBefore(widget.firstDate) || date.isAfter(widget.lastDate)) {
return widget.errorInvalidText ?? MaterialLocalizations.of(context).dateOutOfRangeLabel;
}
return null;
}
void _updateController(TextEditingController controller, String text, bool selectText) {
TextEditingValue textEditingValue = controller.value.copyWith(text: text);
if (selectText) {
textEditingValue = textEditingValue.copyWith(selection: TextSelection(
baseOffset: 0,
extentOffset: text.length,
));
}
controller.value = textEditingValue;
}
void _handleStartChanged(String text) {
setState(() {
_startInputText = text;
_startDate = _parseDate(text);
widget.onStartDateChanged?.call(_startDate);
});
if (widget.autovalidate) {
validate();
}
}
void _handleEndChanged(String text) {
setState(() {
_endInputText = text;
_endDate = _parseDate(text);
widget.onEndDateChanged?.call(_endDate);
});
if (widget.autovalidate) {
validate();
}
}
@override
Widget build(BuildContext context) {
final ThemeData theme = Theme.of(context);
final bool useMaterial3 = theme.useMaterial3;
final MaterialLocalizations localizations = MaterialLocalizations.of(context);
final InputDecorationTheme inputTheme = theme.inputDecorationTheme;
final InputBorder inputBorder = inputTheme.border
?? (useMaterial3 ? const OutlineInputBorder() : const UnderlineInputBorder());
return Row(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Expanded(
child: TextField(
controller: _startController,
decoration: InputDecoration(
border: inputBorder,
filled: inputTheme.filled,
hintText: widget.fieldStartHintText ?? localizations.dateHelpText,
labelText: widget.fieldStartLabelText ?? localizations.dateRangeStartLabel,
errorText: _startErrorText,
),
keyboardType: widget.keyboardType,
onChanged: _handleStartChanged,
autofocus: widget.autofocus,
),
),
const SizedBox(width: 8),
Expanded(
child: TextField(
controller: _endController,
decoration: InputDecoration(
border: inputBorder,
filled: inputTheme.filled,
hintText: widget.fieldEndHintText ?? localizations.dateHelpText,
labelText: widget.fieldEndLabelText ?? localizations.dateRangeEndLabel,
errorText: _endErrorText,
),
keyboardType: widget.keyboardType,
onChanged: _handleEndChanged,
),
),
],
);
}
}