MVF Technical Discussion and Uses (If you plan to Use Them) (2 Viewers)

[RonPaii]

There is no reason to store the data as a delimited list. Store it normalized and display it as delimited text. I started with MajP's sample db and replace the list with a treeview control. The sample form has 2 "MVF", controls displaying the selections as a list and the other fill's the combo box value with delimited list. The user selections tables differ only in name. I am still working on positioning and sizing.

 

[BlueSpruce]

There is no reason to store the data as a delimited list. Store it normalized and display it as delimited text.

That's right!.. That's just what I said to Isladogs and MajP. Store each value, one per record, in a regular child table so I can slice and dice the data with regular queries.

 

[MajP]

Why can't a real listbox control be used to select multiple values that binds each value to a regular table?

Obviously you can do that. That is what people have been doing for years. But that does not give the feel of the MVF combo. The idea was to give you some of the function of an MVF control. Expandable working on the combobox down arrow, checkboxes, ability to close the list. In my case in addition the ability to select all, deselect all, and order the list.

That's right!.. That's just what I said to Isladogs and MajP. Store each value, one per record, in a regular child table so I can slice and dice the data with regular queries

And that is what my original demo showed.

 

[BlueSpruce]

I started with MajP's sample db and replace the list with a treeview control...

Interesting. Does that treeview control work in 64-bit Access? How are values selected from the tree stored? Are there cascading tables for each level of the tree?

 

[BlueSpruce]

Multiselect listboxes are an excellent Access feature which have nothing to do with MVFs

Really? I thought multiselect list boxes used MVF's to store multiple selections.

 

[RonPaii]

Yes, I am using 64-bit Access it works in 32bit without change. The treeview control is filled the same as the original forms in-memory recordset. The data is written back to the user selections table when the ok button is clicked by going though the tree looking for newly checked and un-checked leafs. The available selections table has 3 columns, [SelectionID],[ValueText],[ParentID], processed recursively starting with [ParentID] = 0. Selection tables without structure like the color table pass a query column 0 As [ParentID].