在 flutter 中被点击时如何为我的图标设置动画

Question

I am trying to animate an icon in my app whenever it is being tapped. I achieved the simple animation that i want, but it will always animate once after I come on that screen. I want that it should be animated every time I tap on the IconButton , and it should be rotated clockwise with duration of 2 seconds and when again pressed, rotated anticlockwise with duration of 2 seconds. Please help me

Here is the part of code -

....... 
AnimationController _controller;
  Animation<double> _animation;

@override
  void initState() {
    // TODO: implement initState
    super.initState();
    _cameraController = CameraController(cameras[0], ResolutionPreset.medium, imageFormatGroup: ImageFormatGroup.jpeg);
    cameraValue = _cameraController.initialize();
    _fetchAssets();
    _controller = AnimationController(
      duration: const Duration(seconds: 2),
      vsync: this,
      value: 025,
      lowerBound: 0.0,
      upperBound: 1.0,
    )..repeat();

    _animation = CurvedAnimation(parent: _controller, curve: Curves.linear);

    _controller.forward();
  }

.......

RotationTransition(
                        turns: _animation,
                        child: IconButton(
                          icon: Icon(
                            Icons.flip_camera_ios,
                            color: Colors.white,
                            size: MediaQuery.of(context).size.width*0.07,
                          ),
                          onPressed: () async {
                            setState(() {
                              if(cameraPosition=="Rear") {
                                cameraPosition="Front";
                              }
                              else if(cameraPosition=="Front"){
                                cameraPosition="Rear";
                              }
                            });
                            _cameraController = CameraController(
                              cameras[
                                cameraPosition=="Rear" ? 0
                                : 1
                              ],
                              ResolutionPreset.medium,
                            );
                          },
                        ),
                      ),
........

Answer 1

use the following flutter package: https://pub.dev/packages/scale_button

ScaleButton(
          child: yourIcon())

Answer 2

If you put your icon animation code inside initState(), it will only being triggered once every time you start/restart your screen. To make it being triggered every time you press the IconButton you should copy or move your icon animation code into the onPressed property of the Icon Button, inside the setState() function.