PyGTK recipes

This page lists code snippets for PyGTK that I (as every-once-in-a-while PyGTK user) usually have to search for, or that describe things that are not intuitively to find and that should be documented hence.

For now, this is quite unorganized (probably until there are enough entries to warrant better organization).

The recipes are targeted at

Glade-based apps
somewhat experienced developers (with understanding of programming and basic understanding of Python)

Feel free to add your own recipes.

Basic .glade file loading

Assuming you have a glade file with name myGui.glade, you can load it like this:

   1 import gtk
   2 import gtk.glade
   3 
   4 class MyGUI:
   5     """ Main class for this application (holds the GUI) """
   6     def __init__ (self):
   7         self.tree = gtk.glade.XML("myGui.glade")
   8         self.tree.signal_autoconnect(self)
   9 
  10 if __name__ == "__main__":
  11     h = MyGUI()
  12     gtk.main()

If you have added a handler for the GtkWidget.delete-event in Glade (lets say with a handler named "on_mywindow_delete"), you should add this to your MyGUI class to handle the "close window" event (in this example, by quitting the app):

   1     def on_mywindow_delete (self, widget, dummy):
   2         gtk.main_quit()

Creating a simple list box from a gtk.TreeView

How to create a very simple list box (based on a GtkTreeView control in the glade file):

   1 self.treeview = self.tree.get_widget("myTreeView")
   2 liststore = gtk.ListStore(str) # create a list store with just one column (which holds a string)
   3 self.treeview.set_model(liststore)
   4 
   5 cr = gtk.CellRendererText()
   6 tc = gtk.TreeViewColumn("TheTitle", cr, text=0)
   7 self.treeview.append_column(tc)

(TODO: there must be an easier way to do this! But how??)

To sort the listbox entries alphabetically, add this as well:

   1 liststore.set_sort_column_id(0, gtk.SORT_ASCENDING)

... alternatively, you can make a specific column sortable for the user ("tc" is a TreeViewColumn which was created before; 0 is the index of the liststore column which belongs to the TreeViewColumn):

   1 tc.set_sort_column_id(0)

If you want to have the column sorted right from the beginning, simulate a "click" on the column header like this:

   1 tc.emit("clicked")

(note that for this to work, you must have already added the column to a treeview, with append_column).

Add new entries to the list box like this:

   1 self.treeview.get_model().append(["The Entry Text"])

To react on selection changes you have to handle the "changed" event.

   1 self.treeview.connect("changed", self.on_myTreeView_changed)

... and then implement the handler like this:

   1 def on_myTreeView_changed (self, *args):
   2     selectedItem = self.treeview.get_active() # this is the index of the selected item in the ListStore
   3 
   4     # Note: the 0 at the end specifies the index in the ListStore row
   5     print "selected item has text '%s'" % (self.treeview.get_model()[selectedItem][0])

Using a gtk.TextView control

If you have added a GtkTextView in Glade (lets say with name "myTextView"), do this after loading the .glade file:

   1 self.myTextView = self.tree.get_widget("myTextView")
   2 self.textBuffer = gtk.TextBuffer(None) # we need a gtk.TextBuffer object for storing the actual text
   3 self.myTextView.set_buffer(self.textBuffer)

To append a new line:

   1 self.textBuffer.insert_at_cursor(line, len(line))

To change the whole text at once:

   1 self.textBuffer.set_text(myNewText)

Changing TextView font

   1 textView = self.tree.get_widget("myTextView")
   2 fontName = "Monospace 12"
   3 pangoFont = pango.FontDescription(fontName)
   4 textView.modify_font(pangoFont)

Instead of the hardcoded name you can get the font name also with

   1 fontName = fontDialog.get_font_name()

(TODO: add a "correct way" for setting a TextView to user-preferred monospace font)