Event Callbacks

The SLIDER gadget responds to left-mouse SLIDER START, MOVE, and stop events at which it executes the gadget’s callback if one is defined.

AVEVA recommend you use an open-callback (PML function or form method) as it includes the action 'START', 'MOVE' or 'STOP'. For example, the form method .serviceSlider would have the signature:

define method .serviceSlider( slider is GADGET, action is STRING )

The callbacks for action START and MOVE are not followed by an automatic update, for efficiency reasons, so you may need to follow some gadget modifications carried out in the callback with a !gadget.refresh(), for example, modifying a TEXT gadget to track the SLIDER's current value.

The MOVE callback is generated at each step increment in the SLIDER's range.