Re: PoC: Little improvements to EditGrid - Enum ComboBox

On Wed, 2012-06-06 at 09:33 +0100, Dave Page wrote:
> Hi
>
> On Wed, Jun 6, 2012 at 7:33 AM, Dickson S. Guedes <listas(at)guedesoft(dot)net> wrote:
> > Hello all,
> >
> > I'm starting some proof-of-concept working on frmEditGrid trying make
> > some "improvements" like:
> >
> > 1) show a combo box in columns of type enum;
>
> Nice.
>
> > 2) show a datetime picker in columns of type date/time/timestamp;
>
> Hmm, nice idea in principle, but I'm not sure if there's a suitable
> control that will allow the flexibility required (fractional seconds,
> timezones etc). Obviously that's not needed in all cases, but we
> should be consistent, otherwise we'd get people asking why they can
> use a picker for timestamp but not timestamptz for example.
>
> > 3) show a combo box in columns that has referential to another table;
>
> Also nice, but I think this one needs some careful handling. Perhaps
> limit the combo items to the first 500 or something, and still allow
> the user to manually type a value? We don't want to try to load 10
> million values into the combo!
>
> > For the first item I have a very WIP patch (attached based on commit
> > 896dce8f744816385aa89013d7808960f15a5109) and a working example
> > (attached screenshots and sql) .. I'd like to see your opinions about
> > them, if it is a good idea, and if the initial implementation is
> > following the expectations of such feature. I'd like to know if anyone
> > is/was working in a feature like this, I wouldn't like to reinvent the
> > wheel.
>
> Looks like a great start to me.
>
> > For the second one I'm researching some interaction between
> > wxDatePicker, wxTimePicker and wxCalendarCtrl to create a new type of
> > CellEditor, so we could use some sqlGridDateTimeEditor that
> > encapsulates the logic. Is that a good approach? What is your opinions
> > about that?
>
> Right - see above. Maybe the answer is to develop a popup control that
> can handle date/time/timezone, and yet still allow the user to edit
> manually for things like fractional seconds.
>
> > Finally, for the last one, I see some challenges like:
> >
> > - Which field should be displayed in the combo?
> > Generally the value of a FK doesn't has enough information about
> > what it means, them you need another field (e.g a description or
> > person_name field) to make sense.
>
> Well, you could use a grid instead of a combo box to allow the user to
> choose, and display the FK value in the first column, and the PK value
> from the referenced table in the second and subsequent rows. I think
> anything more than that is probably too domain specific.
>
> > - How to play with composite referential keys? Should they be
> > supported, and if so how should be the behavior?
> > It seems pretty dark to me how to bring values from two fields from
> > a FK in distinct combo boxes.
>
> Yeah, I don't really like the idea of trying to support that case. I
> can't see any sensible way to make it work nicely.
>
> > - Caching the data for performance.
>
> Yes! :-)
>
> > Well, this is just a start point and your opinions is very important.
> >
> > What do you think guys?
>
> I think it'll be a nice addition to the tool - thanks for working on it.
>

+1

> One additional suggestion you may want to include: bytea handling. For
> input, allow the user to select a local file as the contents of a
> bytea field. For output, it would be great if we could detect some
> common filetypes and offer viewers for them - e.g. detect that a bytea
> contains an image and allow the user to view it.
>

And handling of big texts, and NULL values. But even without that, it
would be great to see the enum, and simple FK handling.

--
Guillaume
http://blog.guillaume.lelarge.info
http://www.dalibo.com