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Graeme Geldenhuys · Guest

Hi,

How does MVP handle lookup lists is a Object Maintenance (Edit) form.
For example. I have a Student object which has a Level property
(reference). In the Student Edit form you can change the student's level
using a ComboBox which is a observer (or whatever MVP uses) of a
application Levels lookup list.

There are many more such examples. Like an Employee and a Language or
Country combo box, etc...

Note though, that the combobox contains a lookup list that gets updated
over time, not a static enum type (like Gender [male, female, unknown]).

1) How do you handle something like this with MVP?

2) How do you hookup the GUI and the Object you are editing and the
Lookup list? When you edit the Student, the students correct Level
needs to be selected in the lookup lists ComboBox when the edit form opens.

3) What happens if you are busy editing a Student, and somewhere else in
the program the Levels lookup list gets updated (refreshed from the DB,
or a new lookup item added etc)?

Regards,
- Graeme -

Joanna Carter [TeamB] · Guest

"Graeme Geldenhuys" <graemeg (AT) spamfilter (DOT) co.za> a écrit dans le message de
news: 459a2097 (AT) newsgroups (DOT) borland.com...

| How does MVP handle lookup lists is a Object Maintenance (Edit) form.
| For example. I have a Student object which has a Level property
| (reference). In the Student Edit form you can change the student's level
| using a ComboBox which is a observer (or whatever MVP uses) of a
| application Levels lookup list.

| 1) How do you handle something like this with MVP?

You need an MVP "component" that handles object properties, i.e. proprties
that are of an object type.

| 2) How do you hookup the GUI and the Object you are editing and the
| Lookup list? When you edit the Student, the students correct Level
| needs to be selected in the lookup lists ComboBox when the edit form
opens.

The Interactor knows how to either populate a combobox or popup a selection
dialog and then assign the chosen item to the property that it is managing.

| 3) What happens if you are busy editing a Student, and somewhere else in
| the program the Levels lookup list gets updated (refreshed from the DB,
| or a new lookup item added etc)?

Then you get the snapshot of data available when you dropped the combo list
or opened the dialog. Dynamic updating of a lookup list could prove visually
challenging for a user :-)

Joanna

--
Joanna Carter [TeamB]
Consultant Software Engineer