public Widget _buildAnimation(BuildContext context, Widget child)
{
Color color = widget.controller.status == AnimationStatus.reverse ? _masklessColor : _mask.value;
List <Color> colors = new List <Color>();
colors.Add(color);
colors.Add(color);
return(Positioned.fromRect(
rect: _rect.value,
child: foundation_.kIsWeb
? (Widget) new Container(key: _childGlobalKey, child: widget.child)
: new ShaderMask(
key: _childGlobalKey,
shaderCallback: (Rect bounds) => {
return new LinearGradient(
begin: Alignment.topLeft,
end: Alignment.bottomRight,
colors: colors).createShader(bounds);
},
child: widget.child
)
));
}