getBottom method
Get the bottom position of the widget
Implementation
double getBottom() {
final box = key!.currentContext!.findRenderObject() as RenderBox;
final boxOffset = box.localToGlobal(const Offset(0.0, 0.0));
if (boxOffset.dy.isNaN) return padding.bottom;
final bottomRight = box.size.bottomRight(boxOffset);
return bottomRight.dy + padding.bottom;
}