How can I spin the image along Z axis in flutter? - dart

Question

I am using Transform widget in my flutter code to rotate the screen
Offset _offset = Offset.zero;
return new Transform(
transform: Matrix4.identity()
..setEntry(3, 2, 0.001)
..rotateX(0.01 * _offset.dy)
..rotateY(-0.01 * _offset.dx)
..rotateZ(- 0.01 * _offset.),
alignment: FractionalOffset.center,
child: new Scaffold(
appBar: AppBar(
title: Text("The 3D Matrix"),
),
body: GestureDetector(
onPanUpdate: (details) => setState(() => _offset += details.delta),
onDoubleTap: () => setState(() => _offset = Offset.zero),
child: Content())
),);
Now what I want is to spin the widget along z-axis with certain velocity and slow down it's speed to zero after few seconds.
May be I need to use the Animation Controller. How can we achieve this state?
Right now I achieved this much:

Answer 1

Simply add an AnimationController to your page widget. Then wrap your Transform into a AnimatedBuilder
And when you need to start the animation, call animationController.forward().
class MyHome extends StatefulWidget {
#override
_MyHomeState createState() => _MyHomeState();
}
class _MyHomeState extends State<MyHome> with SingleTickerProviderStateMixin {
AnimationController animationController;
#override
void initState() {
animationController = new AnimationController(
duration: const Duration(seconds: 2),
vsync: this,
);
super.initState();
}
#override
Widget build(BuildContext context) {
return new AnimatedBuilder(
animation: animationController,
builder: (context, child) {
return new Transform(
transform: Matrix4.identity()
..setEntry(3, 2, 0.001)
..rotateZ(animationController.value * 45.0),
child: child,
);
},
child: new Scaffold(
appBar: AppBar(
title: Text("The 3D Matrix"),
),
body: new Center(
child: new RaisedButton(
onPressed: () => animationController.forward(),
child: new Text("Start anim"),
),
),
),
);
}
}