A move_gesture defines the behaviour necessary to allow
the user dragging a graphical
object with the mouse over it's graphical device.
While dragging, the cursor is changed to a fleur
By default, the move_gesture is associated with the middle mouse-button.
->initiate.
->do_set
behaviour so that the distance between the cursor and the top-left
remains the same as when the gesture was initiated.Defaults: button Resource defined (middle) modifiers Resource defined (none)
<-offset
with the distance of the mouse-down event to the top-left corner of the
graphical on which the move is initiated. Sets the cursor to move_gesture.cursor.->drag.<->device not
equal to
@nil.