scroll a frame to display several lines of widgets at a time

[Matt Hammond]

I don't quite understand (if I'm interpreting you correctly) why you want  
separate widgets, all displayed at once, for several hundred records -  
surely better to just reuse the one set of widgets and have the scrollbar  
or back-forward buttons change which record is being displayed in the  
widgets.

If you're after replacing widgets, then you need to destroy them first.  
Use the self.destroy method and unset/change any variables referencing the  
widget so it get a chance to be garbage collected.

However, if you want a scrollable view onto a larger area, what you need  
to do is use a Canvas, with a window shape on it. You then put a frame  
into that window.

    canvas = Tkinter.Canvas( <parent> )
    canvas.grid( ... )
    winID = self.canvas.create_window(0,0, anchor=Tkinter.NW)

Then later you can add a frame to that window on the canvas:

    canvas.itemconfigure( winID, window = <my frame> )
    canvas['scrollregion'] = canvas.bbox('all')

Make sure you've created the frame and perhaps called update_idletasks()  
to give it a chance to size itself before shoving it onto the canvas.

And of course, the scrollbar!

    yscroll = Tkinter.Scrollbar( <parent>, orient=Tkinter.VERTICAL)
    yscroll.grid( ... )
    yscroll['command'] = canvas.yview
    canvas['yscrollcommand'] = yscroll.set


On Thu, 01 Sep 2005 14:33:36 +0100, William Gill <noreply at gcgroup.net>  
wrote:

> I need to display a couple of labels and a checkbox from each entry in  
> my database.  Simple enough, but there are several hundred records, and  
> I only want to display 5 or 10 at a time.  Can this be accomplished by  
> putting everything in a Frame(), using width, height, grid_propagate(0)  
> , and a scrollbar?  or do I have to grid 5 rows at a time?  If the  
> latter, can I just grid over the previous 5 or do they have to be  
> explicitly removed first.
>
> Thanks.
>
> Bill



-- 

| Matt Hammond
| R&D Engineer, BBC Research and Development, Tadworth, Surrey, UK.