interactiveviewer_gallery 0.1.0

Image and video preview component that supports zoom and drag

example/lib/main.dart

import 'package:cached_network_image/cached_network_image.dart';
import 'package:example/display_gesture_widget.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:interactiveviewer_gallery/hero_dialog_route.dart';
import 'package:interactiveviewer_gallery/interactiveviewer_gallery.dart';
import 'package:video_player/video_player.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'InteraGallery Demo',
      // DisplayGesture is just debug, please remove it when use
      home: DisplayGesture(
        child: InteractiveviewDemoPage(),
      ),
    );
  }
}

class DemoSourceEntity {
  String url;
  String previewUrl;
  String type;

  DemoSourceEntity(this.type, this.url, {this.previewUrl});
}

class InteractiveviewDemoPage extends StatefulWidget {
  static final String sName = "/";

  @override
  _InteractiveviewDemoPageState createState() => _InteractiveviewDemoPageState();
}

class _InteractiveviewDemoPageState extends State<InteractiveviewDemoPage> {
  List<DemoSourceEntity> sourceList = [
    DemoSourceEntity('image', 'http://file.jinxianyun.com/inter_05.jpg'),
    DemoSourceEntity('image', 'http://file.jinxianyun.com/inter_02.jpg'),
    DemoSourceEntity('image', 'http://file.jinxianyun.com/inter_03.gif'),
    DemoSourceEntity('video', 'http://file.jinxianyun.com/inter_04.mp4', previewUrl: 'http://file.jinxianyun.com/inter_04_pre.png'),
    DemoSourceEntity('video', 'http://file.jinxianyun.com/6438BF272694486859D5DE899DD2D823.mp4', previewUrl: 'http://file.jinxianyun.com/102.png'),
  ];

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('InteractiveviewerGallery Demo'),
      ),
      body: Padding(
        padding: const EdgeInsets.only(top: 50.0),
        child: Wrap(
          children: sourceList.map((source) => _buildItem(source)).toList(),
        ),
      ),
    );
  }

  Widget _buildItem(DemoSourceEntity source) {
    return Hero(
      tag: source.url,
      placeholderBuilder: (BuildContext context, Size heroSize, Widget child) {
        // keep building the image since the images can be visible in the
        // background of the image gallery
        return child;
      },
      child: GestureDetector(
        onTap: () => _openGallery(source),
        child: Stack(
          alignment: Alignment.center,
          children: [
            CachedNetworkImage(
              imageUrl: source.type == 'video' ? source.previewUrl : source.url,
              fit: BoxFit.cover,
              width: 100,
              height: 100,
            ),
            source.type == 'video'
                ? Icon(
                    Icons.play_arrow,
                    color: Colors.white,
                  )
                : SizedBox(),
          ],
        ),
      ),
    );
  }

  void _openGallery(DemoSourceEntity source) {
    Navigator.of(context).push(
      HeroDialogRoute<void>(
        // DisplayGesture is just debug, please remove it when use
        builder: (BuildContext context) => DisplayGesture(
          child: InteractiveviewerGallery<DemoSourceEntity>(
            sources: sourceList,
            initIndex: sourceList.indexOf(source),
            itemBuilder: itemBuilder,
            heroTagBuilder: (int index) => sourceList[index].url,
          ),
        ),
      ),
    );
  }

  Widget itemBuilder(BuildContext context, int index, bool isFocus) {
    DemoSourceEntity sourceEntity = sourceList[index];
    if (sourceEntity.type == 'video') {
      return DemoVideoItem(
        sourceEntity.url,
        sourceEntity.previewUrl,
        isFocus: isFocus,
      );
    } else {
      return DemoImageItem(sourceEntity.url);
    }
  }
}

class DemoImageItem extends StatefulWidget {
  final String url;

  DemoImageItem(this.url);

  @override
  _DemoImageItemState createState() => _DemoImageItemState();
}

class _DemoImageItemState extends State<DemoImageItem> with AutomaticKeepAliveClientMixin<DemoImageItem> {
  @override
  Widget build(BuildContext context) {
    return Stack(
      children: <Widget>[
        GestureDetector(
          onTap: () => Navigator.of(context).pop(),
        ),
        Align(
          alignment: Alignment.center,
          child: CachedNetworkImage(
            imageUrl: widget.url,
            fit: BoxFit.contain,
          ),
        ),
      ],
    );
  }

  @override
  bool get wantKeepAlive => true;
}

class DemoVideoItem extends StatefulWidget {
  final String url;
  final String preUrl;
  final bool isFocus;

  DemoVideoItem(this.url, this.preUrl, {this.isFocus});

  @override
  _DemoVideoItemState createState() => _DemoVideoItemState();
}

class _DemoVideoItemState extends State<DemoVideoItem> with AutomaticKeepAliveClientMixin<DemoVideoItem> {
  VideoPlayerController _controller;
  VoidCallback listener;
  String localFileName;

  _DemoVideoItemState() {
    listener = () {
      if (!mounted) {
        return;
      }
      setState(() {});
    };
  }

  @override
  void initState() {
    super.initState();
    init();
  }

  init() async {
    _controller = VideoPlayerController.network(widget.url);
    // loop play
    _controller.setLooping(true);
    await _controller.initialize();
    setState(() {});
    _controller.addListener(listener);
  }

  @override
  void dispose() {
    super.dispose();
    _controller.removeListener(listener);
    _controller?.pause();
    _controller?.dispose();
  }

  @override
  void didUpdateWidget(covariant DemoVideoItem oldWidget) {
    super.didUpdateWidget(oldWidget);

    if (oldWidget.isFocus && !widget.isFocus) {
      // pause
      _controller?.pause();
    }
  }

  @override
  Widget build(BuildContext context) {
    return _controller.value.initialized
        ? Stack(
            alignment: Alignment.center,
            children: [
              GestureDetector(
                onTap: () {
                  setState(() {
                    _controller.value.isPlaying ? _controller.pause() : _controller.play();
                  });
                },
                child: AspectRatio(
                  aspectRatio: _controller.value.aspectRatio,
                  child: VideoPlayer(_controller),
                ),
              ),
              _controller.value.isPlaying == true
                  ? SizedBox()
                  : IgnorePointer(
                      ignoring: true,
                      child: Icon(
                        Icons.play_arrow,
                        size: 100,
                        color: Colors.white,
                      ),
                    ),
            ],
          )
        : Theme(data: ThemeData(cupertinoOverrideTheme: CupertinoThemeData(brightness: Brightness.dark)), child: CupertinoActivityIndicator(radius: 30));
  }

  @override
  bool get wantKeepAlive => true;
}