primaryVelocity property Null safety
final
The velocity the pointer was moving along the primary axis when it stopped contacting the screen, in logical pixels per second.
If the GestureDragEndCallback is for a one-dimensional drag (e.g., a horizontal or vertical drag), then this value contains the component of velocity along the primary axis (e.g., horizontal or vertical, respectively). Otherwise, if the GestureDragEndCallback is for a two-dimensional drag (e.g., a pan), then this value is null.
Defaults to null if not specified in the constructor.
Implementation
final double? primaryVelocity;