blob: b372d362f6f74997dc7ae303fb2204eb68b30cd8 [file] [log] [blame]
// Copyright 2013 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:async';
import 'dart:ui' as ui;
import 'package:flutter/foundation.dart'
show SynchronousFuture, describeIdentity, immutable, objectRuntimeType;
import 'package:flutter/rendering.dart';
import 'package:flutter/services.dart';
class _FutureImageStreamCompleter extends ImageStreamCompleter {
_FutureImageStreamCompleter({
required Future<ui.Codec> codec,
required this.futureScale,
}) {
codec.then<void>(_onCodecReady, onError: (Object error, StackTrace stack) {
reportError(
context: ErrorDescription('resolving a single-frame image stream'),
exception: error,
stack: stack,
silent: true,
);
});
}
final Future<double> futureScale;
Future<void> _onCodecReady(ui.Codec codec) async {
try {
final ui.FrameInfo nextFrame = await codec.getNextFrame();
final double scale = await futureScale;
setImage(ImageInfo(image: nextFrame.image, scale: scale));
} catch (exception, stack) {
reportError(
context: ErrorDescription('resolving an image frame'),
exception: exception,
stack: stack,
silent: true,
);
}
}
}
/// Performs exactly like a [MemoryImage] but instead of taking in bytes it takes
/// in a future that represents bytes.
@immutable
class _FutureMemoryImage extends ImageProvider<_FutureMemoryImage> {
/// Constructor for FutureMemoryImage. [_futureBytes] is the bytes that will
/// be loaded into an image and [_futureScale] is the scale that will be applied to
/// that image to account for high-resolution images.
const _FutureMemoryImage(this._futureBytes, this._futureScale);
final Future<Uint8List> _futureBytes;
final Future<double> _futureScale;
/// See [ImageProvider.obtainKey].
@override
Future<_FutureMemoryImage> obtainKey(ImageConfiguration configuration) {
return SynchronousFuture<_FutureMemoryImage>(this);
}
@override
ImageStreamCompleter loadBuffer(
_FutureMemoryImage key,
DecoderBufferCallback decode, // ignore: deprecated_member_use
) {
return _FutureImageStreamCompleter(
codec: _loadAsync(key, decode),
futureScale: _futureScale,
);
}
Future<ui.Codec> _loadAsync(
_FutureMemoryImage key,
DecoderBufferCallback decode, // ignore: deprecated_member_use
) {
assert(key == this);
return _futureBytes.then(ui.ImmutableBuffer.fromUint8List).then(decode);
}
/// See [ImageProvider.operator==].
@override
bool operator ==(Object other) {
if (other.runtimeType != runtimeType) {
return false;
}
return other is _FutureMemoryImage &&
_futureBytes == other._futureBytes &&
_futureScale == other._futureScale;
}
/// See [ImageProvider.hashCode].
@override
int get hashCode => Object.hash(_futureBytes.hashCode, _futureScale);
/// See [ImageProvider.toString].
@override
String toString() => '${objectRuntimeType(this, '_FutureMemoryImage')}'
'(${describeIdentity(_futureBytes)}, scale: $_futureScale)';
}
// ignore: avoid_classes_with_only_static_members
/// Class to help loading of iOS platform images into Flutter.
///
/// For example, loading an image that is in `Assets.xcassts`.
class IosPlatformImages {
static const MethodChannel _channel =
MethodChannel('plugins.flutter.io/ios_platform_images');
/// Loads an image from asset catalogs. The equivalent would be:
/// `[UIImage imageNamed:name]`.
///
/// Throws an exception if the image can't be found.
///
/// See [https://developer.apple.com/documentation/uikit/uiimage/1624146-imagenamed?language=objc]
static ImageProvider load(String name) {
final Future<Map<String, dynamic>?> loadInfo =
_channel.invokeMapMethod<String, dynamic>('loadImage', name);
final Completer<Uint8List> bytesCompleter = Completer<Uint8List>();
final Completer<double> scaleCompleter = Completer<double>();
loadInfo.then((Map<String, dynamic>? map) {
if (map == null) {
scaleCompleter.completeError(
Exception("Image couldn't be found: $name"),
);
bytesCompleter.completeError(
Exception("Image couldn't be found: $name"),
);
return;
}
scaleCompleter.complete(map['scale']! as double);
bytesCompleter.complete(map['data']! as Uint8List);
});
return _FutureMemoryImage(bytesCompleter.future, scaleCompleter.future);
}
/// Resolves an URL for a resource. The equivalent would be:
/// `[[NSBundle mainBundle] URLForResource:name withExtension:ext]`.
///
/// Returns null if the resource can't be found.
///
/// See [https://developer.apple.com/documentation/foundation/nsbundle/1411540-urlforresource?language=objc]
static Future<String?> resolveURL(String name, {String? extension}) {
return _channel
.invokeMethod<String>('resolveURL', <Object?>[name, extension]);
}
}