[Flutter] Why does my Flutter app crash when using a custom widget inside a ListView?

I'm creating a custom widget in Flutter to display a card with some dynamic content. It works perfectly on its own, but when I add it inside a ListView, the app crashes with a 'RenderBox was not laid out' error. Here’s a simplified version of my code:



class MyCustomWidget extends StatelessWidget {

final String title;



MyCustomWidget({required this.title});



@override

Widget build(BuildContext context) {

return Container(

margin: EdgeInsets.all(10),

padding: EdgeInsets.all(20),

child: Text(title),

);

}

}



class MyListScreen extends StatelessWidget {

final List<String> items = ["Item 1", "Item 2", "Item 3"];



@override

Widget build(BuildContext context) {

return Scaffold(

appBar: AppBar(title: Text("My List")),

body: ListView.builder(

itemCount: items.length,

itemBuilder: (context, index) {

return MyCustomWidget(title: items[index]);

},

),

);

}

}



Error Message: RenderBox was not laid out: RenderFlex#... needs an explicit size.

I've tried wrapping the widget in different containers and adjusting alignment properties, but nothing seems to fix it. How can I resolve this issue?"

This approach often receives attention because it includes clear code, a detailed error message, and efforts you've already tried. The key is to be specific and concise so experts can identify the issue quickly. Let me know if you'd like more ideas!

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