Flutter how set background on fix size-CodePudding

I need help. At the moment I'm trying to implement a background on my login page. My problem is that I use a custom shape painter which shows my background.

To make my login page more dynamic I have add a function resizeToAvoidBottomInset: true, to move the textfield over the keyboard.

But now I have the problem that my background will be smaller if I click in my textfield.

Here my login page:

My code:

class _DebugPage extends State<DebugPage> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      resizeToAvoidBottomInset: true,
      appBar: customSubAppBar('Debug', context),
      body: Stack(
        children: [
          //my custom shape painter
          Expanded(
            child: CustomeShapePainer(),
          ),
          //my custom widgets
          _body(context),
        ],
      ),
    );
  }
}

Is there a way to set the background on fix size?

CodePudding user response：

I think you can try set widget CustomeShapePainer wrap Widget Stack. I don't remember exactly but in some projects I did

        child: SingleChildScrollView(
          child: Container(
            color: AppConstants.bgColor,
            height: MediaQuery.of(context).size.height,
            width: MediaQuery.of(context).size.width,
            child: CustomPaint(
              painter: CurvePainter(),
              child: Stack