How to get current Size of button in flutter-CodePudding

So as the question suggests I have a button.

And I want to create a Container that has the exact size of the button. Is there a way to achieve this behaviour?

CodePudding user response：

To find the current size of the button, you can open the flutter inspector and just view the button size in your IDE!

Hope this helps

CodePudding user response：

Just put that button Inside of a container, and copy the height and the width for the new Container

CodePudding user response：

You can achieve that using the key property bound to your button and reading its height from that key and setting it to Container height on WidgetsBinding.instance.addPostFrameCallback like so:

class _TestState extends State<Test> {
  @override
  void initState() {
    WidgetsBinding.instance.addPostFrameCallback((_) {
      setState(() {
        buttonHeight = buttonKey.currentContext?.size?.height ?? 0;
      });
    });
    super.initState();
  }

  final buttonKey = GlobalKey();
  double buttonHeight = 0;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: SafeArea(
        child: Column(
          children: [
            ElevatedButton(
              key: buttonKey,
              onPressed: () {},
              child: Text('button'),
            ),
            Container(
              height: buttonHeight,
              color: Colors.blue,
              alignment: Alignment.center,
              child: Text(
                'button height container',
              ),
            ),
          ],
        ),
      ),
    );
  }
}