> Android development – Rabbit Escape really working on Android

October 7th, 2014

Series: Setup, Menu, Drawing, non-Android, Working, Saving state.

Up until now, you weren’t sure to believe my promises that Rabbit Escape really was going to be an Android game, since I hadn’t actually got it running on Android. Well, the wait is over:

> Showing urgent (flashing) windows on all desktop in LXDE’s taskbar (window list) in Lubuntu

September 25th, 2014

As it stands, lxpanel’s taskbar plugin (part of the LXDE desktop you get with Lubuntu) does not show urgent (flashing) windows if they are on a different virtual desktop from the one you are looking at.

This seems wrong to me (I logged Bug 682), and the fix is a little one-liner:

--- lxpanel.orig/src/plugins/taskbar.c  2013-08-27 23:57:55.000000000 +0100
+++ lxpanel/src/plugins/taskbar.c       2014-09-26 00:48:25.026855589 +0100
@@ -202,10 +202,10 @@
     tk->flash_timeout = g_timeout_add(interval, (GSourceFunc) flash_window_timeout, tk);
-/* Determine if a task is visible considering only its desktop placement. */
+/* Determine if a task is visible considering only its desktop placement and urgency. */
 static gboolean task_is_visible_on_current_desktop(TaskbarPlugin * tb, Task * tk)
-    return ((tk->desktop == ALL_WORKSPACES) || (tk->desktop == tb->current_desktop) || (tb->show_all_desks));
+    return ((tk->desktop == ALL_WORKSPACES) || (tk->desktop == tb->current_desktop) || (tb->show_all_desks) || tk->urgency);
 /* Recompute the visible task for a class when the class membership changes.

To install this patch into Lubuntu, do something like this:

sudo apt-get install build-essential fakeroot dpkg-dev
sudo apt-get build-dep lxpanel
mkdir lxpanel
cd lxpanel
apt-get source lxpanel
cd lxpanel-*
wget https://sourceforge.net/p/lxde/bugs/682/attachment/show-urgent-windows-on-all-desktops.patch
patch -p1 < show-urgent-windows-on-all-desktops.patch
dpkg-buildpackage -rfakeroot -b
cd ..
sudo dpkg -i lxpanel_*.deb
killall lxpanel
lxpanel --profile Lubuntu

> Launch an urgent window using Python and Xlib with the UrgencyHint flag

September 25th, 2014

I am trying to fix a bug in lxpanel’s taskbar plugin, and needed to launch an urgent window. Here’s how I did it in a little python.


# urgent.py -- launch an urgent window (Copyright messages are at the bottom)

# To use:
# sudo apt-get install python-xlib
# ./urgent.py

import sys
import Xlib
from Xlib import X, display, Xutil

d = display.Display()
s = d.screen()
w = s.root.create_window(
    50, 50, 300, 200, 2,
    background_pixel = s.white_pixel,

w.set_wm_name( 'Urgent!' )
w.set_wm_hints( flags = Xutil.UrgencyHint )


    while 1:
        e = d.next_event()
except Xlib.error.ConnectionClosedError:

# This code is based on:
# examples/xrandr.py -- demonstrate the RandR extension
# from http://python-xlib.sourceforge.net/
#    Copyright (C) 2014 Andy Balaam
#    Copyright (C) 2009 David H. Bronke
#    This program is free software; you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation; either version 2 of the License, or
#    (at your option) any later version.
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    GNU General Public License for more details.
#    You should have received a copy of the GNU General Public License
#    along with this program; if not, write to the Free Software
#    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

> Android programming – a non-Android, Android Game

September 24th, 2014

Series: Setup, Menu, Drawing, non-Android, Working, Saving state

We’re planning to write an Android game. So why would we deliberately avoid Android while we’re writing it? To make sure we’re not overly-dependent on the Android ways of doing things, and are able to run our tests etc. on the local machine:

> Android programming – drawing bitmaps in a game loop

September 21st, 2014

Series: Setup, Menu, Drawing, non-Android, Working, Saving state

I will be talking about how to write Android programs that share code with non-Android programs. The program I will be writing is a simple game.

This time we’re writing a game loop and drawing images onto a Canvas using a SurfaceView: