GestureRecognizers now have methods to all the trackpad events from one
continuous trackpad gesture. Calling the addPointerPanZoom method on a
GestureRecognizer with a PointerPanZoomStartEvent will cause the recognizer
to register its interest in that trackpad interaction, and resolve conflicts
between multiple GestureRecognizers that could potentially respond to the
gesture.

The following example shows the proper use of Listener and GestureRecognizer
to respond to trackpad interactions.

void

main

()

runApp

Foo

());

class

Foo

extends

StatefulWidget

late

final

PanGestureRecognizer

recognizer

@override

void

initState

()

super

initState

();