Desing consideration Visible=OFF


Does a LED display with a visible=OFF is pulling is opc data from the server?

SQLTags are polled from the scan class they are attached to. If the scan class is direct or driven than the LED display doesn’t force it to poll. However, if the scan class is set to leased than yes the LED display (even though it is not visible) will force a poll from the OPC server. If a component is bound to something (tag, expression, sql query, etc.) it will run even if the component is not visible.

Will that hold true for enabled/disabled items as well?

Yes, the binding will still happen but the actionPerformed event will not fire if disabled.