| // Copyright 2016 The Chromium 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 'package:flutter/foundation.dart'; |
| import 'package:flutter/material.dart'; |
| |
| import 'drawer.dart'; |
| import 'item.dart'; |
| |
| const double _kFlexibleSpaceMaxHeight = 256.0; |
| const String _kGalleryAssetsPackage = 'flutter_gallery_assets'; |
| |
| class _BackgroundLayer { |
| _BackgroundLayer({ int level, double parallax }) |
| : assetName = 'appbar/appbar_background_layer$level.png', |
| assetPackage = _kGalleryAssetsPackage, |
| parallaxTween = new Tween<double>(begin: 0.0, end: parallax); |
| final String assetName; |
| final String assetPackage; |
| final Tween<double> parallaxTween; |
| } |
| |
| final List<_BackgroundLayer> _kBackgroundLayers = <_BackgroundLayer>[ |
| new _BackgroundLayer(level: 0, parallax: _kFlexibleSpaceMaxHeight), |
| new _BackgroundLayer(level: 1, parallax: _kFlexibleSpaceMaxHeight), |
| new _BackgroundLayer(level: 2, parallax: _kFlexibleSpaceMaxHeight / 2.0), |
| new _BackgroundLayer(level: 3, parallax: _kFlexibleSpaceMaxHeight / 4.0), |
| new _BackgroundLayer(level: 4, parallax: _kFlexibleSpaceMaxHeight / 2.0), |
| new _BackgroundLayer(level: 5, parallax: _kFlexibleSpaceMaxHeight) |
| ]; |
| |
| class _AppBarBackground extends StatelessWidget { |
| const _AppBarBackground({ Key key, this.animation }) : super(key: key); |
| |
| final Animation<double> animation; |
| |
| @override |
| Widget build(BuildContext context) { |
| return new AnimatedBuilder( |
| animation: animation, |
| builder: (BuildContext context, Widget child) { |
| return new Stack( |
| children: _kBackgroundLayers.map((_BackgroundLayer layer) { |
| return new Positioned( |
| top: -layer.parallaxTween.evaluate(animation), |
| left: 0.0, |
| right: 0.0, |
| bottom: 0.0, |
| child: new Image.asset( |
| layer.assetName, |
| package: layer.assetPackage, |
| fit: BoxFit.cover, |
| height: _kFlexibleSpaceMaxHeight |
| ) |
| ); |
| }).toList() |
| ); |
| } |
| ); |
| } |
| } |
| |
| class GalleryHome extends StatefulWidget { |
| const GalleryHome({ |
| Key key, |
| this.useLightTheme, |
| @required this.onThemeChanged, |
| this.timeDilation, |
| @required this.onTimeDilationChanged, |
| this.textScaleFactor, |
| this.onTextScaleFactorChanged, |
| this.showPerformanceOverlay, |
| this.onShowPerformanceOverlayChanged, |
| this.checkerboardRasterCacheImages, |
| this.onCheckerboardRasterCacheImagesChanged, |
| this.checkerboardOffscreenLayers, |
| this.onCheckerboardOffscreenLayersChanged, |
| this.onPlatformChanged, |
| this.onSendFeedback, |
| }) : assert(onThemeChanged != null), |
| assert(onTimeDilationChanged != null), |
| super(key: key); |
| |
| final bool useLightTheme; |
| final ValueChanged<bool> onThemeChanged; |
| |
| final double timeDilation; |
| final ValueChanged<double> onTimeDilationChanged; |
| |
| final double textScaleFactor; |
| final ValueChanged<double> onTextScaleFactorChanged; |
| |
| final bool showPerformanceOverlay; |
| final ValueChanged<bool> onShowPerformanceOverlayChanged; |
| |
| final bool checkerboardRasterCacheImages; |
| final ValueChanged<bool> onCheckerboardRasterCacheImagesChanged; |
| |
| final bool checkerboardOffscreenLayers; |
| final ValueChanged<bool> onCheckerboardOffscreenLayersChanged; |
| |
| final ValueChanged<TargetPlatform> onPlatformChanged; |
| |
| final VoidCallback onSendFeedback; |
| |
| @override |
| GalleryHomeState createState() => new GalleryHomeState(); |
| } |
| |
| class GalleryHomeState extends State<GalleryHome> with SingleTickerProviderStateMixin { |
| static final GlobalKey<ScaffoldState> _scaffoldKey = new GlobalKey<ScaffoldState>(); |
| |
| AnimationController _controller; |
| |
| @override |
| void initState() { |
| super.initState(); |
| _controller = new AnimationController( |
| duration: const Duration(milliseconds: 600), |
| debugLabel: 'preview banner', |
| vsync: this, |
| )..forward(); |
| } |
| |
| @override |
| void dispose() { |
| _controller.dispose(); |
| super.dispose(); |
| } |
| |
| List<Widget> _galleryListItems() { |
| final List<Widget> listItems = <Widget>[]; |
| final ThemeData themeData = Theme.of(context); |
| final TextStyle headerStyle = themeData.textTheme.body2.copyWith(color: themeData.accentColor); |
| String category; |
| for (GalleryItem galleryItem in kAllGalleryItems) { |
| if (category != galleryItem.category) { |
| if (category != null) |
| listItems.add(const Divider()); |
| listItems.add( |
| new MergeSemantics( |
| child: new Container( |
| height: 48.0, |
| padding: const EdgeInsetsDirectional.only(start: 16.0), |
| alignment: AlignmentDirectional.centerStart, |
| child: new SafeArea( |
| top: false, |
| bottom: false, |
| child: new Text(galleryItem.category, style: headerStyle), |
| ), |
| ), |
| ) |
| ); |
| category = galleryItem.category; |
| } |
| listItems.add(galleryItem); |
| } |
| return listItems; |
| } |
| |
| @override |
| Widget build(BuildContext context) { |
| Widget home = new Scaffold( |
| key: _scaffoldKey, |
| drawer: new GalleryDrawer( |
| useLightTheme: widget.useLightTheme, |
| onThemeChanged: widget.onThemeChanged, |
| timeDilation: widget.timeDilation, |
| onTimeDilationChanged: widget.onTimeDilationChanged, |
| textScaleFactor: widget.textScaleFactor, |
| onTextScaleFactorChanged: widget.onTextScaleFactorChanged, |
| showPerformanceOverlay: widget.showPerformanceOverlay, |
| onShowPerformanceOverlayChanged: widget.onShowPerformanceOverlayChanged, |
| checkerboardRasterCacheImages: widget.checkerboardRasterCacheImages, |
| onCheckerboardRasterCacheImagesChanged: widget.onCheckerboardRasterCacheImagesChanged, |
| checkerboardOffscreenLayers: widget.checkerboardOffscreenLayers, |
| onCheckerboardOffscreenLayersChanged: widget.onCheckerboardOffscreenLayersChanged, |
| onPlatformChanged: widget.onPlatformChanged, |
| onSendFeedback: widget.onSendFeedback, |
| ), |
| body: new CustomScrollView( |
| slivers: <Widget>[ |
| const SliverAppBar( |
| pinned: true, |
| expandedHeight: _kFlexibleSpaceMaxHeight, |
| flexibleSpace: const FlexibleSpaceBar( |
| title: const Text('Flutter Gallery'), |
| // TODO(abarth): Wire up to the parallax in a way that doesn't pop during hero transition. |
| background: const _AppBarBackground(animation: kAlwaysDismissedAnimation), |
| ), |
| ), |
| new SliverList(delegate: new SliverChildListDelegate(_galleryListItems())), |
| ], |
| ) |
| ); |
| |
| // In checked mode our MaterialApp will show the default "slow mode" banner. |
| // Otherwise show the "preview" banner. |
| bool showPreviewBanner = true; |
| assert(() { |
| showPreviewBanner = false; |
| return true; |
| }()); |
| |
| if (showPreviewBanner) { |
| home = new Stack( |
| fit: StackFit.expand, |
| children: <Widget>[ |
| home, |
| new FadeTransition( |
| opacity: new CurvedAnimation(parent: _controller, curve: Curves.easeInOut), |
| child: const Banner( |
| message: 'PREVIEW', |
| location: BannerLocation.topEnd, |
| ) |
| ), |
| ] |
| ); |
| } |
| |
| return home; |
| } |
| } |