Modal windows can get lost when switching focus in KDE

[bentoogood]

KDE only:

Switching focus to another application then switching back to gaffer when a modal window (file open dialog for example) is open results in the child window not being re-displayed. Only the parent window is visible, but as control is still with the child no interaction with the parent window is possible (even attempting to close the application).
I have to kill the process and relaunch gaffer.

[bentoogood]

It's possible my KDE window management configuration has some influence on this, so we should find other KDE users test.

[johnhaddon]

I spent some time looking into this with Paulo. We're flagging the dialogue's as Tool windows in order to keep them on top of the window they belong to - otherwise they disappear behind which is very frustrating, especially in full screen mode. When switching apps, KDE closes all the tool windows on the inactive app. On Mac they do the same, but not if the window is currently modal. On GNOME everything works OK too.

There is a setting in the KDE window manager which controls whether or not tool windows are hidden when switching to another app, and turning that off provides a workaround. Maybe we need to catch the hide event when we're modal and immediately reshow ourselves...

[bentoogood]

We will recommend gnome for now and let kde users know about work around.

[andrewkaufman]

Confirmed that #644 fixed the KDE issue.