signal callback delegate or function to connect
void callback(double offsetX, double offsetY, gtk.gesture_drag.GestureDrag gestureDrag)
offsetX X offset, relative to the start point (optional)
offsetY Y offset, relative to the start point (optional)
gestureDrag the instance the signal is connected to (optional)
Yes.After to execute callback after default handler, No.After to execute before (default)
Signal ID
Connect to DragUpdate signal.
Emitted whenever the dragging point moves.