Get widget's absolute coordinates on a screen in Flutter

main.dart

// You can use this extension I wrote (requires Dart 2.6):

extension GlobalKeyEx on GlobalKey {
  Rect get globalPaintBounds {
    final renderObject = currentContext?.findRenderObject();
    var translation = renderObject?.getTransformTo(null)?.getTranslation();
    if (translation != null && renderObject.paintBounds != null) {
      return renderObject.paintBounds
          .shift(Offset(translation.x, translation.y));
    } else {
      return null;
    }
  }
}


// Example how to use it:
final containerKey = GlobalKey();
Rect get containerRect => containerKey.globalPaintBounds;

Container(
  key: containerKey,
  width: 100,
  height: 50,
)

void printContainerWidgetGlobalRect() {
  print('rect: ${containerRect}');
}