PyGTK TextView problems-Collection of common programming errors

I have two problems regarding the TextView widget for PyGTK. How do I dictate the size of the TextView and how do I simply get and insert text (not just set text) into TextView ?

Below is my source code:

import sys

importStatus = False
output = None

try:
    import pygtk
    pygtk.require('2.0')
    import gtk
    importStatus = True

except ImportError:
    print "PyGTK module does not exist. Can't launch GUI !"
    print "Please download and install GTK and PyGTK."
    importStatus = False

if importStatus:

    class gtkGUI():

        def __init__(self):
            print "gtkGUI imported"
            self.startGUI()

        def startGUI(self):
            print "GUI Started"
            self.window = gtk.Window(gtk.WINDOW_TOPLEVEL)
            self.window.set_border_width(10)

            ## Buttons
            self.btn = gtk.Button("Press me !")

            ## Text View with frame wrapping
            self.page_size = gtk.Adjustment(lower=100, page_size=100)
            self.sw = gtk.ScrolledWindow(self.page_size)
            self.sw.set_policy(gtk.POLICY_AUTOMATIC, gtk.POLICY_AUTOMATIC)
            output = gtk.TextView()
            self.textbuffer = output.get_buffer()
            output.set_wrap_mode(gtk.WRAP_WORD)
            output.set_editable(False)
            self.sw.add(output)
            self.frame = gtk.Frame()
            self.frame.set_label(" Result: ")
            self.frame.set_shadow_type(gtk.SHADOW_ETCHED_OUT)
            self.frame.add(self.sw)

            ## Packing widgets into window

            # Vertical box to contain all boxes
            self.vbox = gtk.VBox(homogeneous=False, spacing=0)

            # Output View
            self.vbox.pack_start(self.frame, expand=False, fill=False, padding=5)

            # Adding button to window
            self.box = gtk.HBox(homogeneous=False, spacing=0)
            self.box.pack_end(self.btn, expand=False, fill=False, padding=5)
            self.vbox.pack_start(self.box, expand=False, fill=False, padding=5)

            ## Presenting window
            self.window.add(self.vbox)
            self.window.show_all()
            gtk.main()
            self.insertText("helloworld")
            return None

        def insertText(self, text):
            if(output == None):
                print "Empty Output"
            else:
                print "inserting - " + output

Output when running the above code:

Empty Output

These codes above are the core codes that I have summarized from a bigger codebase containing the essentials to the problem.

Java has a “textarea.append(“…”);” and “textarea.getText()” for Swing. I can’t find anything similar for the TextView in PyGTK.