flutter-layout

问题 I used CustomMultiChildLayout to customize a layout, and implemented MultiChildLayoutDelegate . There are many entries in the layout. I want to change the state when I click on these items, similar to the normal and pressed state of Button in Android. The part of the code is as follows, but it has no effect. Thanks! Build item widget: Color _color = Colors.redAccent; Widget _buildChild(int index) { return LayoutId( id: '$childId$index', child: GestureDetector( onTapDown: (event) { setState(()

问题 I have a very simple control where I am trying to show a DrodownButton with a couple of TextFields. When the app runs in the emulator, I get an error saying "BOTTOM OVERFLOWED BY Infinity PIXELS". The stack trace hints at the issue and points me some relevant documentation, but being very new to Flutter, I'm not sure what needs to change. I have tried all the suggestions based on looking at questions about similar errors, but have not had any luck. I/flutter (10708): ══╡ EXCEPTION CAUGHT BY

问题 I have a Flutter Widget with a column layout that has two Containers, one of which has a ListView.builder . When the page renders I get a bottom overflow by 169px and I'm not sure how to fix it. I've googled around for solutions and have tried various things like wrapping one or more of the Container s in the widget in an Expanded widget, but that doesn't work either. If I wrap just the Container that has the FutureBuilder inside of it in an Expanded , then the ListView doesn't render at all

问题 I want to display data from local json in list as suggestions when user types in a textfield. The suggestions displayed should be based on id that is associated with text to be displayed. Somehow I am not able to achieve to display the data in UI and how to build the hierarchy of widgets that will display suggestions in list . Not sure what am I missing here. Looking for guidance. End result I am looking to achieve is: Json snippet: { "data": [{ "serviceCategory": "ELECTRICAL",

问题 I have a container which look like this which has some background color. I want the list behind the container should be visible. The code written for the container is below: new Container( margin: EdgeInsets.fromLTRB(50.0, 10.0, 50.0, 10.0), width: _isTextFieldActive ? 150.0 : 80.0, height: 40.0, decoration: new BoxDecoration( color: Color(0xFF98DAFC), borderRadius: new BorderRadius.only( topLeft: Radius.circular(0.0), topRight: Radius.circular(32.0), bottomLeft: Radius.circular(0.0),

问题 I'm working on a gridview from flutter framework to achieve a dynamic column count, but didn't get a solution. I have tried using GridView.count and Gridview.builder with itembuilder and i didn't get the expected result. Any help would be appreciated. Please find the image of the design to be achieved. edit : after using staggeredGridview i'm getting the below result return StaggeredGridView.countBuilder( crossAxisCount: 2, itemBuilder: (BuildContext context, int index) { if (index % 2 == 0)

问题 I want to change the background color of Popup Menu Button window. What should I do? I hope I can get your help. Thank you.When I change the color of container, some corners cannot change the color. new IconButton( icon: new Icon( Icons.search, color: Colors.white, ), onPressed: () {}, ), new PopupMenuButton( offset: const Offset(0.0, 60.0), icon: new Icon(Icons.add, color: Colors.white), itemBuilder: (BuildContext context) => <PopupMenuItem<String>>[ new PopupMenuItem<String>( value: '选项一的值'

问题 When I add a image to the card, the Radius at the top of the card are covered. How can I solve it? When I add a image to the card, the Radius at the top of the card are covered. How can I solve it? class App extends StatelessWidget { @override Widget build(BuildContext context) { return MaterialApp( theme: ThemeData(primarySwatch: Colors.yellow), home: Scaffold( backgroundColor: Colors.grey[200], appBar: AppBar(title: Text('Demo'),), body: SizedBox( height: 310.0, child: Card( elevation: 3.0,

问题 I have a Container where I need to show a barcode (it's a app for virtual fidelity cards) and I'd love to have the barcode to be as wide as possible on the screen. For now I set the font size at a reasonable size that suits all devices, but it's only temporary of course. How can I solve this? This is the code I am using for building the Widget. @override Widget build(BuildContext context) { return Scaffold( appBar: AppBar( title: Text(_title), ), body: Container( padding: const EdgeInsets.all

问题 I am new to flutter and having trouble with layouts. I want something like this: A sticky header and a scroll view below it. I thought of using Column widget with two children - first being the header and second being the ListView. Here is my code Widget build(BuildContext context) { return Material( elevation: 8.0, child: Column( crossAxisAlignment: CrossAxisAlignment.start, children: <Widget>[ Padding( padding: const EdgeInsets.all(16.0), child: Text( title, style: Theme.of(context)