我有一个生成特定事件
这段代码片段无法完成此任务。
stream
的函数。现在我有一个来自存储服务的流,它有自己的事件。我正在寻找一种方法,在storage stream
中有变化时产生我的事件。这段代码片段无法完成此任务。
Stream<BlocState> mapEventToState(
BlocEvent event,
) async* {
if (event is UploadData) {
yield UploadDataProgress(progress: 0.0);
final Storage storage = Storage();
final Stream<StorageEvent> upload = storage.upload(event.data);
upload.listen((StorageEvent storageEvent) async* {
print('***** Listener: ${storageEvent.type} - ${storageEvent.progress}');
if (storageEvent.type == StorageEventType.error) {
yield UploadDataError(errorMessage: storageEvent.error);
}
if (storageEvent.type == StorageEventType.success) {
yield UploadDataSuccess();
}
if (storageEvent.type == StorageEventType.progress) {
yield UploadDataProgress(progress: storageEvent.progress);
}
});
}
}
输出: 调试打印可以工作,但事件不会发送到监听器。
***** Listener: StorageEventType.progress - 0.01924033836457124
***** Listener: StorageEventType.progress - 0.044581091468101464
***** Listener: StorageEventType.progress - 0.6986233206170177
***** Listener: StorageEventType.progress - 1.0