Binding

snippet.packages.flutter.lib.src.widgets.binding.105.

  

// ignore_for_file: directives_ordering
// ignore_for_file: unnecessary_import
// ignore_for_file: unused_import
// ignore_for_file: unused_element
// ignore_for_file: unused_local_variable
import 'dart:async';
import 'dart:convert';
import 'dart:math' as math;
import 'dart:typed_data';
import 'dart:ui' as ui;
import 'package:flutter_test/flutter_test.dart';
import 'package:flutter/material.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/widgets.dart';
import 'package:flutter/gestures.dart';
import 'package:flutter/painting.dart';
import 'package:flutter/physics.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/semantics.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter/scheduler.dart';
import 'package:flutter/animation.dart';
import 'package:flutter/services.dart';

// From: packages/flutter/lib/src/widgets/binding.dart:105
class MetricsReactor extends StatefulWidget {
  const MetricsReactor({ Key? key }) : super(key: key);

  @override
  State createState() => _MetricsReactorState();
}

class _MetricsReactorState extends State with WidgetsBindingObserver {
  late Size _lastSize;

  @override
  void initState() {
    super.initState();
    _lastSize = WidgetsBinding.instance.window.physicalSize;
    WidgetsBinding.instance.addObserver(this);
  }

  @override
  void dispose() {
    WidgetsBinding.instance.removeObserver(this);
    super.dispose();
  }

  @override
  void didChangeMetrics() {
    setState(() { _lastSize = WidgetsBinding.instance.window.physicalSize; });
  }

  @override
  Widget build(BuildContext context) {
    return Text('Current size: $_lastSize');
  }
}