我已经看到了几个有关在Firebase存储器中上载文档的示例,但是没有文档将文件列表从Firebase存储器中下载到Flutter。 在Firebase文档上,有许多关于Android,iOS,Web,C ++等的Firebase存储的文档,但没有变化。 特别是如果我谈论视频的
VideoPlayerController videoPlayerController;
@override
void initState() {
videoPlayerController = VideoPlayerController.network('/* Download Url*/');
super.initState();
}
应用初始化时视频的需求网址
答案 0 :(得分:2)
class UploadMultipleImageDemo extends StatefulWidget {
UploadMultipleImageDemo() : super();
final String title = 'Firebase Storage';
@override
UploadMultipleImageDemoState createState() => UploadMultipleImageDemoState();
}
class UploadMultipleImageDemoState extends State<UploadMultipleImageDemo> {
String _path;
Map<String, String> _paths;
String _extension;
FileType _pickType = FileType.video;
bool _multiPick = false;
GlobalKey<ScaffoldState> _scaffoldKey = GlobalKey();
List<StorageUploadTask> _tasks = <StorageUploadTask>[];
void openFileExplorer() async {
try {
_path = null;
if (_multiPick) {
_paths = await FilePicker.getMultiFilePath(
type: FileType.video, );
} else {
_path = await FilePicker.getFilePath(
type: FileType.video, );
}
uploadToFirebase();
} on PlatformException catch (e) {
print("Unsupported operation" + e.toString());
}
if (!mounted) return;
}
uploadToFirebase() {
if (_multiPick) {
_paths.forEach((fileName, filePath) => {upload(fileName, filePath)});
} else {
String fileName = _path.split('/').last;
String filePath = _path;
upload(fileName, filePath);
}
}
upload(fileName, filePath) {
_extension = fileName.toString().split('.').last;
StorageReference storageRef =
FirebaseStorage.instance.ref().child(fileName);
final StorageUploadTask uploadTask = storageRef.putFile(
File(filePath),
StorageMetadata(
contentType: '$_pickType/$_extension',
),
);
setState(() {
_tasks.add(uploadTask);
});
}
String _bytesTransferred(StorageTaskSnapshot snapshot) {
return '${snapshot.bytesTransferred}/${snapshot.totalByteCount}';
}
@override
Widget build(BuildContext context) {
final List<Widget> children = <Widget>[];
_tasks.forEach((StorageUploadTask task) {
final Widget tile = UploadTaskList(
task: task,
onDismissed: () => setState(() => _tasks.remove(task)),
onDownload: () => downloadFile(task.lastSnapshot.ref),
);
children.add(tile);
});
return MaterialApp(
home: new Scaffold(
key: _scaffoldKey,
appBar: new AppBar(
title: Text(widget.title),
),
body: new Container(
padding: EdgeInsets.all(20.0),
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
mainAxisAlignment: MainAxisAlignment.start,
children: <Widget>[
OutlineButton(
onPressed: () => openFileExplorer(),
child: new Text("Open file picker"),
),
SizedBox(
height: 20.0,
),
Flexible(
child: ListView(
children: children,
),
),
],
),
),
),
);
}
Future<void> downloadFile(StorageReference ref) async {
final String url = await ref.getDownloadURL();
final http.Response downloadData = await http.get(url);
final Directory systemTempDir = Directory.systemTemp;
final File tempFile = File('${systemTempDir.path}/tmp.jpg');
if (tempFile.existsSync()) {
await tempFile.delete();
}
await tempFile.create();
final StorageFileDownloadTask task = ref.writeToFile(tempFile);
final int byteCount = (await task.future).totalByteCount;
var bodyBytes = downloadData.bodyBytes;
final String name = await ref.getName();
final String path = await ref.getPath();
print(url);
_scaffoldKey.currentState.showSnackBar(
SnackBar(
backgroundColor: Colors.white,
content: Image.memory(
bodyBytes,
fit: BoxFit.fill,
),
),
);
}
}
class UploadTaskList extends StatelessWidget {
const UploadTaskList(
{Key key, this.task, this.onDismissed, this.onDownload})
: super(key: key);
final StorageUploadTask task;
final VoidCallback onDismissed;
final VoidCallback onDownload;
String get status {
String result;
if (task.isComplete) {
if (task.isSuccessful) {
result = 'Complete';
} else if (task.isCanceled) {
result = 'Canceled';
} else {
result = 'Failed ERROR: ${task.lastSnapshot.error}';
}
} else if (task.isInProgress) {
result = 'Uploading';
} else if (task.isPaused) {
result = 'Paused';
}
return result;
}
String _bytesTransferred(StorageTaskSnapshot snapshot) {
return '${snapshot.bytesTransferred}/${snapshot.totalByteCount}';
}
@override
Widget build(BuildContext context) {
return StreamBuilder<StorageTaskEvent>(
stream: task.events,
builder: (BuildContext context,
AsyncSnapshot<StorageTaskEvent> asyncSnapshot) {
Widget subtitle;
Widget prog;
Widget progtext;
if (asyncSnapshot.hasData) {
final StorageTaskEvent event = asyncSnapshot.data;
final StorageTaskSnapshot snapshot = event.snapshot;
subtitle = Text('$status: ${_bytesTransferred(snapshot)}');
double _progress = event.snapshot.bytesTransferred.toDouble() / event.snapshot.totalByteCount.toDouble();
prog = LinearProgressIndicator(
value: _progress,
backgroundColor: Colors.red,
);
progtext = Text('${(_progress * 100).toStringAsFixed(2)} %');
} else {
subtitle = const Text('Starting...');
}
return Dismissible(
key: Key(task.hashCode.toString()),
onDismissed: (_) => onDismissed(),
child: ListTile(
title: subtitle,
// Text('Upload Task #${task.hashCode}'),
subtitle: prog,
trailing: Row(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Offstage(
offstage: !task.isInProgress,
child: IconButton(
icon: const Icon(Icons.pause),
onPressed: () => task.pause(),
),
),
Offstage(
offstage: !task.isPaused,
child: IconButton(
icon: const Icon(Icons.file_upload),
onPressed: () => task.resume(),
),
),
Offstage(
offstage: task.isComplete,
child: IconButton(
icon: const Icon(Icons.cancel),
onPressed: () => task.cancel(),
),
),
Offstage(
offstage: !(task.isComplete && task.isSuccessful),
child: IconButton(
icon: const Icon(Icons.file_download),
onPressed: onDownload,
),
),
],
),
),
);
},
);
}
}
答案 1 :(得分:0)
要找到从Flutter上传和下载文件到Cloud Storage的示例,请查看FlutterFire库firebase_storage
的{{3}}。
该过程主要包括获取下载URL,该URL可让您以只读方式访问文件:
final String url = await ref.getDownloadURL();
然后使用以下方法从该URL加载数据:
final http.Response downloadData = await http.get(url);
查看example application以获取完整示例。