Hot to use Fade Animations in Flutter

fade_animation.dart

    body: Center(
        child:
        FadeTransition(
          opacity: _myAnimation,
          child: Container(
            width: 100,
            height: 100,
            decoration: BoxDecoration(
                image: new DecorationImage(
                    image: new AssetImage(
                      'assets/images/ghost.png',
                    )
                )
            ),
          ),
        )
    ),