In D10785#214018, @rkflx wrote:

I guess your patch did no lack proper testing and you just uploaded the wrong revision :D

Even when your test plan contains a weird case, the most basic function should work too: Open Gwenview, toggle Thumbnail Bar, quit.

Apologies, I was too hasty in submitting this patch. I swear I tested the above though...

I wonder if we can get rid of mThumbnailBarVisibleBeforeFullScreen? In fullscreen mode we always hide the thumbnailbar, and in normal mode it could just directly read the config value (see also a similar refactoring Peter did recently in c2e8c8923841). Not sure if it will work, though, because the menubar checkbox has to be in sync.

I've updated it (and hopefully tested thoroughly enough!), to work like this:

• The checked state of the thumbnail bar action is used to track what the user wants
• Fullscreen sets the visibility of the bar directly, without toggling the action
• When saving the config, we use the checked state of the action

What this means is that if the thumbnail bar is visible in normal mode, going to fullscreen will hide it but the button/action will remain checked to indicate the state the user wants it in (which fullscreen overrides). In Normal mode, they should stay in sync.
Therefore in a way, the checked state of the action is replacing mThumbnailBarVisibleBeforeFullScreen.

Not sure whether this is a 'good' way of doing it.