Re: Thoughts on the ComboBox framework

[Havoc Pennington <hp redhat com>]

On Mon, Mar 31, 2003 at 05:10:20PM -0500, Owen Taylor wrote: 
> On Mon, 2003-03-31 at 16:17, Havoc Pennington wrote:
> > On Mon, Mar 31, 2003 at 03:49:29PM -0500, Owen Taylor wrote: 
> > >  GtkOptionBox
> > > 
> > 
> > I strongly hate GtkOptionBox. ;-) The advantage of using a familiar
> > term (ComboBox, OptionMenu) easily outweighs the technicality that it
> > can look like either one.
> 
> I was *not* thinking of it as a portmanteau-combination of 
> GtkOptionMenu and GtkComboBox; but rather just as GtkOptionThingy.
> The problem with GtkComboBox is that the typical use case
> is not clearly a "combination" of anything. GtkChoice?

That problem is just a technicality IMO, people are used to the name
combo for this widget from other APIs (they have trouble finding
OptionMenu), so if it's called Combo they'll find it. Most of us don't
actually *know* why it's called a combo anyhow. ;-)

Plus if you have the HistoryEntry as a subclass and allow
set_sample_widget() then GtkComboBox *is* accurate, so there 
isn't even a technicality to worry about.

> So, your interface really needs to look a lot like GtkTreeModel:
> with incremental notification of additions, deletions
> and changes to current rows. You could do the whole thing
> as:
>  
>  gtk_entry_set_completions_tree_model ()
>  
> And leave the updating of that on ::changed up to the app.
> That would work if you don't want GTK+ doing the searching.
> But "give me the completion" definitely doesn't work 
> since we need a list and "give me the completions" (plus
> a "completions changed, ask me again") is, in my guess,
> going to be slower and more flickery than stuffing everything
> into a tree.
> 

That makes sense to me.

> What the widgets have in common is not the _implementation_ of
> the popdown button, but the quite complicated _interface_ of the
> what gets displayed in the dropdown list / menu, and somewhat less
> importantly, the _interface_ of "an item in the drop down list was
> selected".

Ah, if you want to allow custom random stuff in the entry dropdown
that's true. I was thinking that the entry dropdown had to display
strings and nothing else, and that the only possible action on "an
item was selected" would be to put said item in the entry.

I guess I can imagine putting pixmaps in the entry dropdown, such as
favicons for URLs. Not sure I can imagine an action on select other
than putting the text in the entry, but I'm sure people can think of
something. ;-) 

Havoc