halkyon/third_party/keyboard_height_plugin/lib/keyboard_height_plugin.dart

import 'dart:async';
import 'package:flutter/services.dart';

typedef KeyboardHeightCallback = void Function(double height);

class KeyboardHeightPlugin {
  static const EventChannel _keyboardHeightEventChannel =
      EventChannel('keyboardHeightEventChannel');

  StreamSubscription? _keyboardHeightSubscription;

  void onKeyboardHeightChanged(KeyboardHeightCallback callback) {
    if (_keyboardHeightSubscription != null) {
      _keyboardHeightSubscription!.cancel();
    }
    _keyboardHeightSubscription =
        _keyboardHeightEventChannel.receiveBroadcastStream().listen(
      (dynamic height) {
        callback(height as double);
      },
    );
  }

  void dispose() {
    if (_keyboardHeightSubscription != null) {
      _keyboardHeightSubscription!.cancel();
    }
  }
}