Re: Sorting Integer value treeview column

[Jason Brisbane <darkeen westnet com au>]

Thanks.

Every time I used G_TYPE_INT in the gtk_list_store_new function the 
value returned wasnt the INT as expected. The value shown was an 8 digit 
number that didnt have any relation to the int as shown in the mysql 
client. I believe it was a pointer.

So I tried using a double (G_TYPE_DOUBLE) and adding the data via : 2, 
g_ascii_strtod(db_row[2], NULL),

I got the desired result, although it did padd the result with trailing 
zeroes...
So the program was behaving with the results...

So I tried one last version...Typeing with INT64... (G_TYPE_INT64)
and hooking the database value returned with the function:

2, g_ascii_strtoull(db_row[2], NULL, 10 ),

TADA! The value dispayed in the list was the integer I expected. The 
sort of the list worked a treat!

Just a pointer for those who might have the same problems...



David Nec(as (Yeti) wrote:
> On Sat, May 05, 2007 at 06:20:05PM +0800, Jason Brisbane wrote:
>   
> > I have a treeview that is populated with an Integer value (from a mysql 
> > database) that is populated into a G_TYPE_STRING.
> >     
>
> Why?  Inappropriate data representation is the source of all
> your problems.
>
>   
> > This displays 
> > correctly but the sort function using:
> >           gtk_tree_view_column_set_sort_column_id (col, x);
> >           gtk_tree_view_column_set_sort_indicator (col, TRUE);
> >
> > sorts the values as Alphanumeric, not numeric.
> > ...
> >
> > Do I need to hook in a Sort function and use the Modelsort instead of Model?
> >     
>
> You do if you want to keep integers represented as strings.
>
>   
> > Should sorting a integer value be a basic function of a treeview/liststore?
> >     
>
> It *can* sort by integer columns.  GtkCellRendererText can
> even diplay (format) a G_TYPE_INT column without the need of
> an explicitly set cell data function.
>
> But if you want to sort strings by some random associated
> value you have to tell it how to compare these values.
>
>   
> > Should I be setting an attribute of the column as "integer" instead of 
> > "text"?
> >     
>
> No, you should use integer data model (i.e. G_TYPE_INT) for
> integers.  If you need to present them as text, format them
> to text: either by using GtkCellRendererText built-in
> capabilities or an explicite cell data function that sets
> the "text" attribute.
>
> If rendering the presentation is very expensive, you may
> want to cache the presentations in the model *in addition*
> to the primary value, but this is not the case anyway.
>
> I attach a simple program that demonstrates sorting by
> two integer columns: one presented as plain number the other
> as date+time.
>
> Yeti
>
> --
> http://gwyddion.net/
>
>
>   
<SNIP>

--
---
Regards,

Jason Brisbane