UIHANDLER OnUpdate

Fires when drawing the user interface (many times per second). (self, elapsed)

Payload

 * self : - The updated widget.
 * elapsed : - The time in seconds since the last OnUpdate dispatch, but excluding time when the user interface was not being drawn such as while zoning into the game world

Details

 * Preceeded by handlers associated with processing user input.
 * Blocked by a frame or its parent.
 * OnUpdate is resource intensive because it fires as often as the client can draw new frames -- potentially hundreds of FPS with modern computers.
 * It is usually better to substitute or  to skip frames, or to apply an  for animating a widget.
 * Alternatively, throttle slower parts of an OnUpdate handler by measuring the passage of time and only performing work as often as reasonably necessary.

Examples
Throttles a workload no more than once every 0.05 seconds:

Executes a workload 20 times per second. If FPS is slower than 20, the workload repeats until caught up.