I need to load list cities dynamically from rest webservice and let user choose a city from alert dialog.My code:
createDialog() { fetchCities().then((response) { showDialog( context: context, builder: (BuildContext context) { return AlertDialog( title: Text('Wybierz miasto'), content: Container( height: 200.0, width: 400.0, child: ListView.builder( shrinkWrap: true, itemCount: response.length, itemBuilder: (BuildContext context, int index) { return ListTile( title: Text(response[index].name), onTap: () => citySelected(response[index].id), ); }, ), ), ); } ); }); }Result - dialog is always 200x400, even if only 2 cities are available, there is an unnecessary room left at the bottom:
How to make dialog width/height to fit actual items size? If I ommit height and width parameters, I'm getting exception and no dialog shown. In native Android Java I never need to specify any dimensions, because dialog sizes itself automatically to fit.
How to fix my code to get dialog sized correctly? Note: that I don't know item count, it's dynamic.
[edit]
As suggested, I wrapped content with column:
createDialog() { fetchCities().then((response) { showDialog( context: context, builder: (BuildContext context) { return AlertDialog( title: Text('Wybierz miasto'), content: Column( mainAxisSize: MainAxisSize.min, children: <Widget>[ Container( child: ListView.builder( shrinkWrap: true, itemCount: response.length, itemBuilder: (BuildContext context, int index) { return ListTile( title: Text(response[index].name), onTap: () => citySelected(response[index].id), ); }, ), ) ] ), ); } ); }); }Result - exception:
I/flutter ( 5917): ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY╞═════════════════════════════════════════════════════════ I/flutter (5917): The following assertion was thrown during performLayout():I/flutter ( 5917): RenderViewport does not support returning intrinsicdimensions. I/flutter ( 5917): Calculating the intrinsic dimensionswould require instantiating every child of the viewport, whichI/flutter ( 5917): defeats the point of viewports being lazy.
More generic code to test:
showDialog( context: context, builder: (BuildContext context) { return AlertDialog( title: Text('Select city'), content: Column( mainAxisSize: MainAxisSize.min, children: <Widget>[ Container( child: ListView.builder( shrinkWrap: true, itemCount: 2, itemBuilder: (BuildContext context, int index) { return ListTile( title: Text("City"), onTap: () => {}, ); }, ), ) ] ), ); } );