======== Exception caught by widgets library ======================================================= The following assertion was thrown building CanvasTouchDetector(dirty, state: _CanvasTouchDetectorState#84c03): Incorrect GestureDetector arguments.
Having both a pan gesture recognizer and a scale gesture recognizer is redundant; scale is a superset of pan.
Just use the scale gesture recognizer.
I found a solution as follow:
add
gesturesToOverride: [GestureType.onTapDown],
on CanvasTouchDetector
CanvasTouchDetector( gesturesToOverride: [GestureType.onTapDown], builder: (context) => .......