copy_size_widget 1.0.0

A widget that sizes itself using another widget's size.

example/lib/main.dart

import 'dart:math';

import 'package:copy_size_widget/copy_size_widget.dart';
import 'package:flutter/material.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
        useMaterial3: true,
      ),
      home: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key, required this.title});

  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  double _size = 200;
  final copyKey = GlobalKey();

  void _incrementCounter() {
    setState(() {
      _size = Random().nextInt(300).toDouble();
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.spaceBetween,
          children: <Widget>[
            CopySizeWidget(
              copyKey: copyKey,
              child: Container(
                color: Colors.red,
                child: const Placeholder(),
              ),
            ),
            Container(
              key: copyKey,
              color: Colors.blue,
              width: _size,
              height: _size,
              child: const Placeholder(),
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: const Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}