Keyboard-aware Tkinter listbox?

[Martin Franklin]

On Wednesday 15 May 2002 2:07 pm, Stephen Ferg wrote:
> I've been using the Tkinter LISTBOX, but it seems to have some
> limitations.  Other LISTBOX implementations that I'm familiar with
> automatically sort the list of entries and support keyboard selection.
>  By keyboard selection, I mean that if you had a list like this:
> So... I thought that before I try to build this myself,  I'd like to
> ask if anyone knows if this has already been done?
>


Steve,

Tkinter does not have this functionallity but it would not be too hard to 
roll your own, basically bind <Any-Key> to a function that searches through 
you list box contents (a sorted list object will do) when it finds on that 
matches call the selection_set and see methods on the Listbox add a pinch of 
salt and your done!


somthing like.....(barely tested!)

import string
import Tkinter


class AutoListbox(Tkinter.Frame):
    def __init__(self, parent, list_data=[]):
        Tkinter.Frame.__init__(self, parent)
        self.listbox=Tkinter.Listbox(self)
        self.listbox.pack()
        self.list_data=list_data
        self.list_data.sort()
        self.setlist()
        parent.bind('<Any-Key>', self.bound)
        
        
    def setlist(self):
        self.listbox.delete(0, 'end')
        for thing in self.list_data:
            self.listbox.insert('end', thing)
        
        
    def bound(self, event):
        key=event.keysym
        if len(key)<=1:
            if key in string.letters:
                ## print key # now find it in list.....
                
                
                ## before we clear get the selected 
                try:
                    start_n=int(self.listbox.curselection()[0])
                except IndexError:
                    start_n=-1
                ## clear the selection.
                self.listbox.selection_clear(0, 'end')
                ## start from previous selection +1
                for n in range(start_n+1, len(self.list_data)):
                    item=self.list_data[n]
                    if item[0].lower()==key.lower():
                        self.listbox.selection_set(first=n)
                        return
                else:
                    # has not found it so loop from top
                    for n in range(len(self.list_data)):
                        item=self.list_data[n]
                        if item[0].lower()==key.lower():
                            self.listbox.selection_set(first=n)
                            ## should call see method but don't have
                            ## scrollbars in this demo!
                            return
                
        
if __name__=='__main__':
    root=Tkinter.Tk()
    alb=AutoListbox(root, list_data=['abc', 'bcd', 'bcde', 'cdefg'])
    alb.pack()
    root.mainloop()





HTH
Martin