4.5. Table Packing Example

The example program table.py makes a window with three buttons in a 2x2 table. The first two buttons will be placed in the upper row. A third, quit button, is placed in the lower row, spanning both columns. Figure 4.6, “Packing using a Table” illustrates the resulting window:

Figure 4.6. Packing using a Table

Packing using a Table

Here's the source code:

    1	#!/usr/bin/env python
    2	
    3	# example table.py
    4	
    5	import pygtk
    6	pygtk.require('2.0')
    7	import gtk
    8	
    9	class Table:
   10	    # Our callback.
   11	    # The data passed to this method is printed to stdout
   12	    def callback(self, widget, data=None):
   13	        print "Hello again - %s was pressed" % data
   14	
   15	    # This callback quits the program
   16	    def delete_event(self, widget, event, data=None):
   17	        gtk.main_quit()
   18	        return False
   19	
   20	    def __init__(self):
   21	        # Create a new window
   22	        self.window = gtk.Window(gtk.WINDOW_TOPLEVEL)
   23	
   24	        # Set the window title
   25	        self.window.set_title("Table")
   26	
   27	        # Set a handler for delete_event that immediately
   28	        # exits GTK.
   29	        self.window.connect("delete_event", self.delete_event)
   30	
   31	        # Sets the border width of the window.
   32	        self.window.set_border_width(20)
   33	
   34	        # Create a 2x2 table
   35	        table = gtk.Table(2, 2, True)
   36	
   37	        # Put the table in the main window
   38	        self.window.add(table)
   39	
   40	        # Create first button
   41	        button = gtk.Button("button 1")
   42	
   43	        # When the button is clicked, we call the "callback" method
   44	        # with a pointer to "button 1" as its argument
   45	        button.connect("clicked", self.callback, "button 1")
   46	
   47	
   48	        # Insert button 1 into the upper left quadrant of the table
   49	        table.attach(button, 0, 1, 0, 1)
   50	
   51	        button.show()
   52	
   53	        # Create second button
   54	
   55	        button = gtk.Button("button 2")
   56	
   57	        # When the button is clicked, we call the "callback" method
   58	        # with a pointer to "button 2" as its argument
   59	        button.connect("clicked", self.callback, "button 2")
   60	        # Insert button 2 into the upper right quadrant of the table
   61	        table.attach(button, 1, 2, 0, 1)
   62	
   63	        button.show()
   64	
   65	        # Create "Quit" button
   66	        button = gtk.Button("Quit")
   67	
   68	        # When the button is clicked, we call the main_quit function
   69	        # and the program exits
   70	        button.connect("clicked", lambda w: gtk.main_quit())
   71	
   72	        # Insert the quit button into the both lower quadrants of the table
   73	        table.attach(button, 0, 2, 1, 2)
   74	
   75	        button.show()
   76	
   77	        table.show()
   78	        self.window.show()
   79	
   80	def main():
   81	    gtk.main()
   82	    return 0       
   83	
   84	if __name__ == "__main__":
   85	    Table()
   86	    main()

The Table class is defined in line 9-78. Lines 12-13 define the callback() method which is called when two of the buttons are "clicked". The callback just prints a message to the console indicating which button was pressed using the passed in string data.

Lines 16-18 define the delete_event() method which is called when the window is slated for deletion by the window manager.

Lines 20-78 define the Table instance initialization method __init__() . It creates a window (line 22), sets the window title (line 25), connects the delete_event() callback to the "delete_event" signal (line 29), and sets the border width (line 32). A gtk.Table is created in line 35 and added to the window in line 38.

The two upper buttons are created (lines 41 and 55), their "clicked" signals are connected to the callback() method (lines 45 and 59), and attached to the table in the first row (lines 49 and 61). Lines 66-72 create the "Quit" button, connect its "clicked" signal to the main_quit() function and attach it to the table spanning the whole second row.