onLoad method
Implementation
Future<void> onLoad() async {
await _loader?.load();
_spriteToRender = sprite;
if (spriteBackgroundDirection == null) {
_paintBackground = Paint()
..color = color.withOpacity(opacityBackground)
..style = PaintingStyle.fill;
}
if (sprite == null) {
_paintAction = Paint()
..color = color.withOpacity(opacityKnob)
..style = PaintingStyle.fill;
}
if (spritePressed == null) {
_paintActionPressed = Paint()
..color = color.withOpacity(opacityBackground)
..style = PaintingStyle.fill;
}
_loader = null;
}