isUnique
Checks if @action represents a single action or includes multiple actions.
When @action is 0 - ie no action was given, true is returned.
Return
true if exactly one action was given
Parameters
action
a GdkDragAction
Checks if @action represents a single action or includes multiple actions.
When @action is 0 - ie no action was given, true is returned.
true if exactly one action was given
a GdkDragAction