Touchscreen - can't select panel menu items. (20.04)


Well, this one has me stumped! I have a new touch screen ( connected to an udoo-x86 single board computer. I've just installed Ubuntu MATE 20.04 and it looks and works fantastic, except a little problem that I can't seem to sort.

I can select menu items on the panel with the touchscreen. Both global menu and app indicator menus pop up, but if I select a menu item it highlights it for an instant but won't select it.

Everything else works exactly as expected - Brisk menu works fine, both Mutiny and Familiar versions. Menus within apps like Firefox and Libre Office work perfectly with the touch screen and the 'onboard' keyboard works great too. It is just panel menu items, and only with the touchscreen - I can connect a mouse and it all works as it should.

I'm stuck as I'm not sure if this is a kernel or software problem. I tried the screen on another single board computer I have running ubuntu Budgie 19.10 and could select everything fine.

have I missed something obvious?!? Thanks loads for any help!

1 Like

I can confirm error on HP Stream 8 tablet

I already saw that the menus work fine in applications like Firefox and LibreOffice, but they don't work in the global app menu or the menus for the indicators.

But do the menus work in an application such as Pluma?

The global app menu, the indicators, and Pluma all use a library called GTK+ for almost all of the work they do; Firefox and LibreOffice only use GTK+ so that they can blend in with the desktop. Firefox and LibreOffice only use GTK+ for drawing a (limited) amount of stuff -- they do not use GTK+ to handle user interaction; the other three applications I mentioned do use GTK+ for user interaction.

Try opening Pluma, then selecting something in the Pluma menu. If Pluma doesn't have its own menu, switch to the panel layout called Traditional if possible (search the Brisk menu for MATE Tweak and launch that application to change panel layouts).

If you cannot select stuff in the Pluma menu either, then the common factor is GTK+. If you can, then the common factor is some component of the panel -- considering both the global app menu and the indicators are Canonical/Ubuntu products, maybe there's a connection there?