[Tutor] Scrolling multilistbox help

[Alberto Troiano]

Hey tutors

I'm using the Multilistbox class and I noticed that it only handles the 
mouse scroll and the scrollbar to go down or up.I succesfully implemented 
the sort function that came with the class
I also added code to handle the up and down arrow keys and it goes down all 
right but only select the item and it doesn't scroll down or up

How can make it go up or down?
I'm sendind the class here:

class MultiListbox(Frame):
    fila=0
    sortedBy=-1
    def __init__(self, master, lists):
	Frame.__init__(self, master)
	self.lists = []
	for l,w,a in lists:
	    frame = Frame(self,background="red"); frame.pack(side=LEFT, expand=YES, 
fill=BOTH)
	    Button(frame,background="red",foreground="white",font="Verdana 8 
bold",text=l, borderwidth=1, relief=RAISED,command=lambda a=a: 
self._sortBy(a)).pack(fill=X)
	    lb = Listbox(frame, width=w, borderwidth=0, selectborderwidth=0,
			 relief=FLAT, exportselection=FALSE)
	    lb.pack(expand=YES, fill=BOTH)
	    self.lists.append(lb)
	    lb.bind('<B1-Motion>', lambda e, s=self: s._select(e.y))
	    lb.bind('<Double-Button-3>', lambda e, s=self: s._devolverfila(e.y))
	    lb.bind('<Return>', lambda e, s=self: s._devolverfila(e.y))
	    lb.bind('<Button-1>', lambda e, s=self: s._select(e.y))
	    lb.bind('<Down>', lambda s: _select1())
                    lb.bind('<Up>', lambda s: _select2())
	    lb.bind('<Leave>', lambda e: 'break')
	    lb.bind('<B2-Motion>', lambda e, s=self: s._b2motion(e.x, e.y))
	    lb.bind('<Button-2>', lambda e, s=self: s._button2(e.x, e.y))
	frame = Frame(self,background="red"); frame.pack(side=LEFT, fill=Y)
	Label(frame,background="red",foreground="white",font="Verdana 8 bold", 
borderwidth=1, relief=RAISED).pack(fill=X)
	sb = Scrollbar(frame,background="red", orient=VERTICAL, 
command=self._scroll)
	sb.pack(expand=YES, fill=Y)
	self.lists[0]['yscrollcommand']=sb.set

    def _sortBy(self, column):
        """ Sort by a given column. """
        if column == self.sortedBy:
            direction = -1 * self.direction
        else:
            direction = 1
        elements = self.get(0, END)
        self.delete(0, END)
        elements.sort(lambda x, y: self._sortAssist(column, direction, x, 
y))
        self.insert(END, *elements)
        self.sortedBy = column
        self.direction = direction

    def _sortAssist(self, column, direction, x, y):
        if column!=0:
            c = cmp(x[column], y[column])
            if c:
                return direction * c
            else:
                return direction * cmp(x, y)
        else:
            c = cmp(int(x[column]), int(y[column]))
            if c:
                return direction * c
            else:
                return direction * cmp(x, y)

    def _select(self, y):
	row = self.lists[0].nearest(y)
	self.selection_clear(0, END)
	self.selection_set(row)
	self.fila=row
	return 'break'

    def _devolverfila(self, y):
	row = self.lists[0].nearest(y)
	self.selection_clear(0, END)
	self.selection_set(row)
	self.fila=row

    def _select1(self):
        if self.fila==self.size()-1:
            pass
        else:
            self.selection_clear(0, END)
    	    self.selection_set(self.fila+1)
            self.fila+=1
            self._scroll()
	return 'break'

    def _select2(self):
    	if self.fila==0:
            pass
        else:
            self.selection_clear(0, END)
            self.selection_set(self.fila-1)
            self.fila-=1
	return 'break'

    def _button2(self, x, y):
	for l in self.lists: l.scan_mark(x, y)
	return 'break'

    def _b2motion(self, x, y):
	for l in self.lists: l.scan_dragto(x, y)
	return 'break'

    def _scroll(self, *args):
	for l in self.lists:
	    apply(l.yview, args)

    def curselection(self):
	return self.lists[0].curselection()

    def delete(self, first, last=None):
	for l in self.lists:
	    l.delete(first, last)

    def get(self, first, last=None):
	result = []
	for l in self.lists:
	    result.append(l.get(first,last))
	if last: return apply(map, [None] + result)
	return result

    def index(self, index):
	self.lists[0].index(index)

    def insert(self, index, *elements):
	for e in elements:
	    i = 0
	    for l in self.lists:
		l.insert(index, e[i])
		i = i + 1

    def size(self):
	return self.lists[0].size()

    def see(self, index):
	for l in self.lists:
	    l.see(index)

    def selection_anchor(self, index):
	for l in self.lists:
	    l.selection_anchor(index)

    def selection_clear(self, first, last=None):
	for l in self.lists:
	    l.selection_clear(first, last)

    def selection_includes(self, index):
	return self.lists[0].selection_includes(index)

    def selection_set(self, first, last=None):
	for l in self.lists:
	    l.selection_set(first, last)


THanks in advanced

Alberto