Mouse Double Click is an Extension that provides two new GML functions, mouse_doubleclick_init() and mouse_check_doubleclick()
Written in pure GML, these new functions round out the built-in Mouse functions, allowing you to easily check for double-click events.
To use it, first call the mouse_doubleclick_init() function in the Create event for the object that will be handling click actions. This creates an instance variable used to perform timing checks for the double-click, like so:
//Create Event: mouse_doubleclick_init();
In a Step or Mouse event, call mouse_check_doubleclick(), passing in parameters for the mouse button to test for, and the doubleclick delay in microseconds (1/1,000,000th of a second).
//Mouse Event mouse_check_doubleclick(mb_left, 250000); //250000 microseconds = 1/4 of a second
mouse_check_doubleclick() will return true if there were two clicks within the duration specified by the second argument, and false if no double click is detected.
That’s all there is to it.