onTertiaryTapDown property Null safety

GestureTapDownCallback? onTertiaryTapDown
final

A pointer that might cause a tap with a tertiary button has contacted the screen at a particular location.

This is called after a short timeout, even if the winning gesture has not yet been selected. If the tap gesture wins, onTertiaryTapUp will be called, otherwise onTertiaryTapCancel will be called.

See also:

Implementation

final GestureTapDownCallback? onTertiaryTapDown;