Flutter: Incorrect use of ParentDataWidget, when using Expanded inside SingleChildScrollView-CodePudding

Below is the hierarchy of my Widgets. The SingleChildScrollView and Expanded were added simply because I wish to get the RefreshIndicator working.

Scaffold
  SingleChildScrollView
    Expanded
      RefreshIndicator
        Column

It was working until I upgrade my flutter recently and caused the following error Incorrect use of ParentDataWidget

I have did a search, the problem seems like because Expanded widget can only reside in Column, Row or Flex

I put the expanded in any of the widgets above will results in either the refresh not working or another weird error.

Again, my main intention is to have my RefreshIndicator working inside a Scaffold.

CodePudding user response：

In Flutter if you use SingleChildScrollView with Expanded then it will never work. And if you want to keep both widgets in your code then Wrap your Expanded with Column widget. Your Column widget should be parent widget of your Expanded widget , not in it's child widget.

CodePudding user response：

But you don't need to use the expend widget for the refresh indicator. Just try with the below code:

Scaffold(
      body: new RefreshIndicator(
        child: SingleChildScrollView(
          child: Center(
            child: Column(
              children: List.generate(50,  (f) => Text("Item $f")),
            ),
          ),
        ),
        onRefresh: _refresh,
      ),
    )

//refresh function

Future<Null> _refresh() async{
    print('refreshing........');
  }