Detecting when PopupApplet is iconified

[Rob Hasselbaum]

On Fri, Mar 19, 2010 at 2:05 PM, Aaron J. Seigo <aseigo at kde.org> wrote:
> On March 19, 2010, Rob Hasselbaum wrote:
>> It's expensive. So just blocking the updates from propagating between
>> the data engine and the applet isn't enough.
>
> if nothing it connected to a source and the source was created using
> sourceRequestEvent() it is automatically removed.

Yup. That's exactly what I'm relying on. When the applet becomes
hidden, I'm disconnecting from the source and the data engine becomes
idle unless there is some other visualization connected to that source
or a different one. Works as advertised.

>> And a nice benefit of
>> pausing the data engine's work is that the applet becomes idle on its
>> own.
>
> * dataengines are inherently shared between visualizations (that's actually
> kind of the entire point of them); so this won't work if one visualization
> (applet, e.g.) is shown and the other isn't

Right, I should have mentioned that my dataUpdate slot also throws
away any data it gets for the source after it has disconnected, so it
truly becomes idle.