How to detect hardware button press in flutter

Question

I am building an app that starts by pressing the hardware button (Android/ios volume up button) for a long time, but I can't find any way to do it, Is there any way to do it?

Answer 1

UPDATED ANSWER:

For iOS/Android:

check out this package:

• Volume Watcher Package

---

For Desktop/Web:

You can use Focus widget or RawKeyboardListener widget to listen to keyboard events.

Here's a simple example:

@override
Widget build(BuildContext context) {
  return Focus(
    autofocus: true,
    onKeyEvent: (node, event) {
      if (event.physicalKey == PhysicalKeyboardKey.keyA) {
        if (event is KeyDownEvent) {
          // the user started pressing the key A
        } else if (event is KeyRepeatEvent) {
          // the user is pressing the key A
        } else if (event is KeyUpEvent) {
          // the user stopped pressing the key A
        }
        // if you handled the event (prevent propagating the events further)
        return KeyEventResult.handled;
      }
      // otherwise return this (propagates the events further to be handled elsewhere)
      return KeyEventResult.ignored;
    },
    child: Container(),
  );
}

I'm using a macbook with touchbar so I couldn't confirm the volume up but you can replace PhysicalKeyboardKey.keyA with PhysicalKeyboardKey.audioVolumeUp.

Also, instead of using autofocus, you can use a FocusNode and pass it to the Focus widget to control when the widget has focus (i.e. when it should listen to events).

References:

• a list of all physical keys (just go to the definition of PhysicalKeyboardKey on the IDE to see the list): keyboard_key.dart

• The rendered documentation page with a DartPad example: PhysicalKeyboardKey class