Unresponsive touch events on Galaxy S6

[tomasz ankudowicz]

Hey all, I started playing with Kivy and noticed some unresponsiveness on my Galaxy S6. On both, the showcase and my own app launched via Kivy Launcher, I'm unable to click TabbedPanelItem to switch to selected tab and dropdown items on Showcase' Spinner. Everything else works fine and additionally both widgets are fully responsive on another device (Nexus 5)!

I assume there is something wrong with my phone's Android settings. I checked some previous threads and people had gestures and triple tap zoom enabled. This is not the case with my phone and I'm slowly running out of ideas. Before figuring out that this is related to specific device, I spent days trying to adjust my TabbedPanel source code ;)

Any help will be appreciated.
-t

[Damien Moore]

One thought... Check all your on_touch_* handlers and make sure you aren't returning True (which will stop propagating to other widgets) when you should be returning False. I only suggest this because the propagation order appears to vary on some devices.

[Filip Demaertelaere]

I think you fall into a known problem.

There are several bug report open for it.

See eg https://github.com/kivy/kivy/issues/4031 (which refers to other similar open topics).

Op zondag 24 juli 2016 14:04:20 UTC+2 schreef tomasz ankudowicz:

[Damien Moore]

If it's only affecting a few widgets then I don't see how it's a hardware issue.

I would put some logger statements in these methods:

https://github.com/kivy/kivy/blob/master/kivy/uix/behaviors/button.py#L137

https://github.com/kivy/kivy/blob/master/kivy/uix/tabbedpanel.py#L164

And then see what is going on in adb

[tomasz ankudowicz]

Thanks guys for the answers. Yes, I think this is the same problem and from other topics on kivy/issues I understand that this started in 1.9.1. However, the error is quite old and I don't see any upcoming solution.

I was not precise in my initial thread: the event actually works after continuous 20-30 touches. Sometimes faster, sometimes later. I tested my app on 3 other devices and Galaxy S6 is the only one affected. It might be related to the high density screen, but not sure yet. The fact that this appears in the Showcase makes me thinking that it's just a kivy problem.

I also noticed that the Showcase TabbedPanel example works fine, but their implementation is a bit different: they use on_release in their kv, while I followed documentation (https://kivy.org/docs/api-kivy.uix.tabbedpanel.html) without specifying any on_ methods. I just rely on TabbedPanel's on_touch_down method.

Damien, I will do the logger as soon as I can (I'm currently traveling), but since this is only visible on Android, how would you implement it? As a print to a Label on the screen to see where the delay is actually created?

[Damien Moore]

Print will work, but you can also use Kivy's logger class. You use adb logcat to monitor the output of the phone (you will see print and logger output this way). What's trickier might be finding the correct location in the filesystem where you can edit the kivy module files.