I'm trying to make a hight picker and using a image along with the number of height.i want when user pick any height number the size of image increase or decrease according to the selected Height number.

CodePudding user response：

Try as follows:

  class MyHomePage extends StatefulWidget {
  const MyHomePage({Key? key}) : super(key: key);
 
  @override
  _MyHomePageState createState() => _MyHomePageState();
}
 
class _MyHomePageState extends State<MyHomePage> {
   
  var items = [   
    200,
    300,
    400,
    
  ];
  var index=0;
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text("Test"),
      ),
      body: Column(
      children:[
        ListView.builder(
          shrinkWrap:true,
          itemCount:items.length,
        itemBuilder:(ctx,i){
          return TextButton(onPressed:(){
            setState((){
              index=i;
            });
          },child:Text(items[i].toString()));
        }
        ),
        Image.network("https://images.unsplash.com/photo-1453728013993-6d66e9c9123a?ixlib=rb-1.2.1&ixid=MnwxMjA3fDB8MHxzZWFyY2h8Mnx8dmlld3xlbnwwfHwwfHw=&w=1000&q=80",
                      height:items[index].toDouble()
                     ),
      ]
      )
    );
  }
}

CodePudding user response：

Please refer to below code example

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  final TextEditingController heightControl = TextEditingController();
  final ValueNotifier<double> height1 = ValueNotifier<double>(200);
  final ValueNotifier<double> _height2 = ValueNotifier<double>(120);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: AnimatedBuilder(
        animation: Listenable.merge([
          height1,
          _height2,
        ]),
        child: null,
        builder: (BuildContext context, _) {
          return Stack(
            children: <Widget>[
              Positioned(
                left: 30,
                right: 30,
                bottom: 10,
                child: Column(
                  children: <Widget>[
                    InkWell(
                      onTap: () {
                        height1.value = 80.0;
                      },
                      child: Container(
                        color: Colors.transparent,
                        height: height1.value,
                        child: Stack(
                          clipBehavior: Clip.none,
                          children: [
                            Image.network(
                              'https://images.stockfreeimages.com/2911/sfi226w/29118870.jpg',
                              fit: BoxFit.fill,
                              height: height1.value,
                            ),
                            Text(
                              "Current Height ${height1.value} \n Tap to reduce height",
                              style: TextStyle(
                                color: Colors.white,
                              ),
                            ),
                          ],
                        ),
                      ),
                    ),
                    InkWell(
                      onTap: () {
                        _height2.value = 290.0;
                      },
                      child: Container(
                        color: Colors.orange,
                        height: _height2.value,
                        child: Stack(
                          clipBehavior: Clip.none,
                          children: [
                            Image.network(
                              'https://images.stockfreeimages.com/5439/sfi226w/54392167.jpg',
                              fit: BoxFit.fill,
                              height: _height2.value,
                            ),
                            Text(
                                'Current height : ${_height2.value} \n Tap to increase height'),
                          ],
                        ),
                      ),
                    ),
                  ],
                ),
              ),
            ],
          );
        },
      ),
    );
  }
}