Flutter can't read from Clipboard

问题

I come asking for quite a specific question regarding Flutter and the Future and await mechanism, which seems to be working, but my Clipboard does not really function while operating with my editable text fields, even following Google's advice on implementation...

This is my code for pasting:

onPressed: () async {
  await getMyData('text');
  _encodingController.text = clipData;
  Scaffold.of(context).showSnackBar(
    new SnackBar(
      content: new Text(
        "Pasted from Clipboard"),
      ),
    );
},

what doesnt work is my paste functionality... While debugging the result of this following function is null, wth?????????

static Future<ClipboardData> getMyData(String format) async {
    final Map<String, dynamic> result =
        await SystemChannels.platform.invokeMethod(
      'Clipboard.getData',
      format,
    );

    if (result == null) {
      return null;
    } else {
      clipData = ClipboardData(text: result['text']).text;
      return ClipboardData(text: result['text'].text);
    }
  }

I am probably using the Futures and async await wrong, would love some guidance!!! Copying is working using the Clipboard Manager plugin! Thanks very much!

回答1:

Or you just can use the Flutter's basic way:

ClipboardData data = await Clipboard.getData('text/plain');

That's work like charm.

回答2:

It's works for me:

  _getFromClipboard() async {
    Map<String, dynamic> result =
        await SystemChannels.platform.invokeMethod('Clipboard.getData');
    if (result != null) {
      return result['text'].toString();
    }
    return '';
  }

回答3:

Also can be useful if you want to listen for periodic updates from the system clipboard. Originally I replied here, just re-posting the solution:

#creating a listening Stream:
final clipboardContentStream = StreamController<String>.broadcast();

#creating a timer for updates:
Timer clipboardTriggerTime;

clipboardTriggerTime = Timer.periodic(
# you can specify any duration you want, roughly every 20 read from the system
      const Duration(seconds: 5),
      (timer) {
        Clipboard.getData('text/plain').then((clipboarContent) {
          print('Clipboard content ${clipboarContent.text}');

          # post to a Stream you're subscribed to
          clipboardContentStream.add(clipboarContent.text);
        });
      },
    );

# subscribe your view with
Stream get clipboardText => clipboardController.stream

# and don't forget to clean up on your widget
@override
void dispose() {
  clipboardContentStream.close();

  clipboardTriggerTime.cancel();
}

回答4:

First create a method

Future<String> getClipBoardData() async {
        ClipboardData data = await Clipboard.getData(Clipboard.kTextPlain);
        return data.text;
      }

Then in build method

FutureBuilder(
                future: getClipBoardData(),
                initialData: 'nothing',
                builder: (context, snapShot){
                  return Text(snapShot.data.toString());
                },
              ),

来源：https://stackoverflow.com/questions/53392726/flutter-cant-read-from-clipboard

标签

asynchronous

dart

Flutter

clipboard

future