Hi Boris,
I made a simple GUI app with a textbox that pops up and disappears when required. However, whenever this popup appears I want nitpicker to immediately change focus to this popup and put it in front of all other nitpicker clients and windows. Now the behaviour is either "click", "transient" or "none", meaning the focus is only given when the user clicks on the window, or never.
I had to solved this exact problem in the Sculpt scenario where the control panel "Leitzentrale" should always have the keyboard focus while activated. Otherwise, the regular nitpicker focus policy should be in place. I hope that my solution works equally well for your scenario:
Please have a look at the combination of the 'nit_user_focus' and 'nit_focus' components in the sculpt.run script [1]. The former captures the state of the regular nitpicker focus. The latter overrides the former whenever the Leitzentrale is enabled.
[1] https://github.com/nfeske/genode/blob/sculpt/repos/gems/run/sculpt.run
Cheers Norman