Griffon: the Quickly connection

The following is but a preview of the capabilities exposed by the Griffon Gtk plugin. Ubuntu's Quickly is a desktop application framework inspired by Rails. It lets you build Gtk+Python applications in a snap (is there any doubt that a new breed of desktop application frameworks was needed?), in a similar fashion as Griffon lets you do it.

Quickly applications rely on XML formatted files to describe their UI elements. These files can be parsed using Glade. It turns out that the java-gnome supports parsing glade files too; and the griffon-gtk plugin relies on java-gnome to do its thing. I think you can guess where this conversation is headed

If you have an Ubuntu distro on your machine you can install Quickly by issuing the following command


Once you have Quickly installed you create a basic project with the following commands:


If you inspect the contents of foo/data/ui you'll find all the UI definitions that can be parsed at bootstrap in order to construct the application's user interface. We're ready to build a Griffon application that will have the same user interface. The first step would be to create a Griffon application project.


Now we copy all media files to the application's resource directory


Where $FOO_HOME points to the directory that contains the foo application created by the quickly command. Then we copy the target glade file, in this case we'll only copy the main window


Once the griffon-gtk plugin is installed (must be built from source at the moment, you won't find it at the central plugin repository) the View script is certainly very simple
application(title: 'quick', width: 600, height: 500, icon: pixbuf('icon.png')) { glade('foo-window.glade', embed: 'vbox1') }
The glade node instructs the builder to search for a glade file in the classpath, parse its contents and insert a widget whose id matches 'vbox1'. If you inspect the contents of foo-window.glade you'll find that vbox1 is the only child of the topmost window. However if you attempt to run the application right now you'll encounter a few errors. I have not located the source of the problem yet, it may be java-gnome's parsing capabilities or Quickly's version of glade xml, truth is you need to make some adjustments before getting some results. These are the required adjustments that need to be made on foo-window.glade

1. change <interface> to <glade-interface>
2. comment out <requires lib="gtk+" version="2.16"/>
3. change all <object> elements to <widget>
4. remove type="submenu" from every menu widget
5. comment out the image1 element, we'll insert it on the Groovy side.

That last change is needed because java-gnome attempts to load background.png from a temporal directory instead of the application's resource directory. The last step would be to update the View script with the following code
application(title: 'quick', width: 600, height: 500, icon: pixbuf('icon.png')) { glade('foo-window.glade', embed: 'vbox1'){ back = image('background.png') noparent { vbox1.reorderChild(back, 2) } } }
Note how an image node is nested inside the glade node (which resolves to vbox1) so the actual image is embedded into vbox1; the only change left is to reorder the nodes on vbox1.

These steps take care of reusing Quickly UI definitions on a Griffon application. What about the application's logic? If only there was a way to run python code on the JVM (hint, hint )

Keep on Groovying!