Problems running Python3.4/GObject (GTK3.0)

[katadelos]

Hi,

I've been experimenting with packaging GTK3 with the corresponding Python3.4 bindings and have been having trouble with running a simple test application. When the test application included is run, the buttons are not drawn on the screen of the Kindle but do respond to touch events. The window title seems to be set correctly, so I'm curious as to what is causing this issue.

Any thoughts?

I've included the script that I'm using to download and extract packages from the Debian Jessie repo, which is a modified version of the script from this thread. To build the environment, run python3 build.py.

[katadelos]

Update:

On the advice of @NiLuJe, I removed Python from the equation entirely and compiled a minimal GTK3 application to see whether the problem lay with Python or GTK3. When I ran my compiled binary, I had the same outcome as before - the titlebar turned invisible but none of the widgets were drawn. However, when I ran my application within Xephyr, it worked perfectly. I also tried to run one of the Python/GTK examples within Xephyr and I had different results depending on whether I was within a debian chroot or not. Outside of the chroot, GTK tried to load fontconfig definitions from the usual system path and failed with a bunch of errors like this:

Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 84: Having multiple <family> in <alias> isn't supported and may not work as expected
Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 84: Having multiple <family> in <alias> isn't supported and may not work as expected
Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 93: Having multiple <family> in <alias> isn't supported and may not work as expected
Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 93: Having multiple <family> in <alias> isn't supported and may not work as expected
Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 102: Having multiple <family> in <alias> isn't supported and may not work as expected
Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 102: Having multiple <family> in <alias> isn't supported and may not work as expected

The program loads but the text doesn't display properly, as shown in the image below. When I'm within the chroot, this is not an issue, presumably because it's loading the font config files from within the chroot.

Why does GTK work within Xephyr but not directly on the Kindle's X11 server?

[NiLuJe]

I can't comment on the X thing as I'm not familiar with any of it, but the fontconfig thing *is* familiar .

That's a simple version mismatch: the config format evolved in some release long ago, which made newer configs partly unreadable by older versions. Or vice-versa.

This was fun for a while even on desktop, with apps that bundle fontconfig and/or fontconfig shards (looking at you, CEF & Electron ).

[NiLuJe]

You can force fontconfig's searchpath via env vars to work around the config mismatches somewhat, without having to do anything crazier.

IIRC, FONTCONFIG_FILE points to the "master" fonts.conf (i.e., what's usually /etc/fonts/fonts.conf). This can point to a bogus path if you just need to discard everything (which was my own use-case, but that was a pretty edge-casey one ;p).

There may be finer-grained approaches, check fontconfig's docs .