Okay! Here goes. I started with a base installation of Volumio 1.2 beta and installed X, the Matchbox WM and Midori on top of that.
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install xserver-xorg xserver-xorg-core xfonts-base xinit xserver-xorg-input-evdev
sudo apt-get install matchbox
sudo apt-get install midori
Then added an .xsession in the home of the default user “pi” and symlinked it to .xinitrc just to be sure (The symlink may not be required. I’m far from an expert in Linux and am not familiar with Raspbian at all).
Using nano to enter the following into .xsession:
sudo nano .xsession
Enter the lines below and use CTRL-X to save and exit.
midori -e fullscreen -a localhost & matchbox-window-manager -use_titlebar no
Then the symlink and starting X, you should now see a fullscreen browser with Volumio’s GUI.
ln -s .xsession .xinitrc
That will get you where you want to be if you only want to add a display to Volumio. Note that it won’t start on boot at this point, you’ll need to change that still if that’s what you want.
To get the 15" touch screen going I had to modify config.txt to adapt to its native resolution
Touch will work out of the box but not exactly hitting the right spot. To build and run the calibration tool I ran the following:
sudo apt-get install gcc build-essential
sudo apt-get install libx11-dev libxext-dev libxi-dev x11proto-input-dev
tar xvzf xinput_calibrator-0.7.5.tar.gz
sudo make install
Then you can run xinput_calibrator in X to properly calibrate the touch screen.
Now, for my project, I’m figuring out how to configure Matchbox with a nice matchbox-panel in the bottom for navigation to other things (Google Calendar, recipes, etc) and how to get matchbox-keyboard, the virtual on screen keyboard, to play nicely (autohide when not needed for example). Might have to try a few different keyboards for that, I also installed onboard and florence to have a look.