dragOffsetNotifier property

dragOffsetNotifier - Only used on iOS and Android

QuillRawEditor contains a gesture detector EditorTextSelectionGestureDetector within it's widget tree that includes a RawMagnifier. The RawMagnifier needs the current position of selection drag events in order to display the magnifier in the correct location. Setting the position to null will hide the magnifier.

Initial selection events are posted by EditorTextSelectionGestureDetector. Once a selection has been created, dragging the selection handles happens in EditorTextSelectionOverlay.

Both EditorTextSelectionGestureDetector and EditorTextSelectionOverlay will update the value of the dragOffsetNotifier.

The EditorTextSelectionGestureDetector will use the value to display the magnifier in the correct location (or hide the magnifier if null). EditorTextSelectionOverlay will use the value of the dragOffsetNotifier to hide the context menu when the magnifier is displayed and show the context menu when dragging is complete.