Re: Suppresing events to avoid fibrillation

Roedy Green wrote:
I run into this problem frequently. I call it fibrillation.

Lets say I do a setText on some component. This triggers an event on
it. That event handler then might do setText's on other components.
If you are really unlucky, you get a circularity.

What would like to do is a sneaky programmatic setText that does NOT
trigger any events, other than perhaps a repaint.

What I have been doing is somewhat klutzy. I have some ad hoc
booleans. When I don't want an event to be acted on, I set the
boolean, then detect it in the event handler, and turn it off.

You need one boolean for each possible event that might be triggered.
If it is not triggered, the event improperly stays suppressed.

Is there a clean way to do this?
Use a shared model amongst all your views. Don't listen for changes on a particular visual element, but instead have the business logic handled in your model. This also will help prevent coupling your business model to GUI.

The other possibility is to check for an actual "difference" in value before setting off other events.

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