title: Horizontal scrollbar treeview in Tkinter
body: <p>I have some problems with the treeview of Tkinter and the horizontal scrollbar.
  The scroll bar does not seem to work. It looks like a Tk bug.</p>
  
  <p>I can not post pictures or links, sorry.</p>
  
  <p>When I click on the branches to expand, the scrollbar does not work.</p>
  
  <pre><code>from Tkinter import *
  import ttk
  
  
  root = Tk()     
  
  frame = Frame(root)
  
  tree = ttk.Treeview(frame, selectmode='browse')
  
  scrollbar_horizontal = ttk.Scrollbar(frame, orient='horizontal', command = tree.xview)    
  scrollbar_vertical = ttk.Scrollbar(frame, orient='vertical', command = tree.yview)   
  scrollbar_horizontal.pack(side='bottom', fill=X)    
  scrollbar_vertical.pack(side='right', fill=Y)
  
  tree.configure(xscrollcommand=scrollbar_horizontal.set, yscrollcommand=scrollbar_vertical.set)
  
  tree.pack(side=LEFT, fill=BOTH, expand=False)
  
  frame.pack(expand=False)
  
  tree.insert('', '0', 'it_titulo', text='Matematicas')    
  tree.insert('', '1', 'it_aritmetica', text='Aritmetica')    
  tree.insert('', '2', 'it_algebra', text='Algebra')    
  tree.insert('', 'end', 'it_geometria', text='Geometria')
  
  tree.insert('it_aritmetica', '0', 'prop_sum', text='Propiedades de la suma')    
  tree.insert('it_aritmetica', '1', 'prop_res', text='Propiedades de la resta')    
  tree.insert('it_aritmetica', '2', 'prop_mul', text='Propiedades de la multiplicacion')    
  tree.insert('it_aritmetica', '3', 'prop_div', text='Propiedades de la division')   
  tree.insert('it_aritmetica', 'end', 'art_repaso', text='Repaso')    
  
  tree.insert('it_algebra', '0', 'alg_ele', text='Algebra Elemental')    
  tree.insert('it_algebra', '1', 'alg_int', text='Algebra Intermedia')    
  tree.insert('it_algebra', '2', 'alg_avz', text='Algebra Avanzada')    
  tree.insert('it_algebra', 'end', 'alg_repaso', text='Repaso')    
  
  tree.insert('alg_ele', '0', 'prop_conm_adn', text='Propiedad conmutativa de la adicion')
  
  root.mainloop()
  </code></pre>