onStart property Null safety
read / write
The pointers in contact with the screen have established a focal point and initial scale of 1.0.
This won't be called until the gesture arena has determined that this GestureRecognizer has won the gesture.
See also:
- https://flutter.dev/docs/development/ui/advanced/gestures#gesture-disambiguation, which provides more information about the gesture arena.
Implementation
GestureScaleStartCallback? onStart;