deselecting items in listbox after certain other item choosen.

Hughesie78 · February 23rd, 2009, 06:11 AM

I have list box on a windows form in windows application app in VB.NET, the list box contains 9 items, the items are populated from a database.
The values selected on the listbox are then used to built up a SQL statement which is then sent to create a report.
My problem is, I want the list box to deselect all other options when one particular one is selected,

Item 1
Item 2
Item 3
Item 4

So Items 2,3 4 can all be selected together, but when Item 1 is selected I want all others to be deselect in the SelectedIndexChanged event.
Any ideas?

gbianchi · February 23rd, 2009, 07:37 AM

Sure! Every time you have a selectedindexchanged event raised, Loop through all the collection, and deselect the items you don't want...

Hughesie78 · March 19th, 2009, 09:11 AM

Ok, still have this issue… here is my code:
' i= 0, once this is selected I want all the others to be deselected, but I also want the user to be able to reselect the others aswell without having to manually unselect 0, there are 9 items in the list. I want the users to be able to select multiples only for 1-9, but once zero selected all the others are unselected.

If lstSt.Items.Count >= 0 Then

For i = 0 To lstStore.Items.Count - 1
If lstStore.GetSelected(i) = True And i <> 0 Then

Else

End If

Next i

End If
End if

ANy Ideas?

gbianchi · March 19th, 2009, 09:41 AM

ok, so what's the problem?

Hughesie78 · March 19th, 2009, 09:45 AM

Ok, so basically when I selected item 0 I want all other to be unselected, but I also want the user to be able to reselt the other other items in case they change their mind.
Item 0 = is basically and group of shops
Items 1-9 = individual

You see what im trying to do, I want the user to selected either Group of shops – v- individual shops

gbianchi · March 19th, 2009, 10:26 AM

Yes, but you realized that the user interface is confusing?? checkbox mean to be not exclusive each other (so, item 0 shouldn't be a check box!).
Beside the UI problem, I still don't understand where is your problem?? if the item 0 is checked, deselect all the rest, if the user checks any of the rest, deselect 0.

Hughesie78 · March 19th, 2009, 10:29 AM

Hey

Im using a list box control not a check box.
And yes how you described how is should work is perfect,( if the item 0 is checked, deselect all the rest, if the user checks any of the rest, deselect 0.) im looking for the code to do it. This would be a great help.

gbianchi · March 19th, 2009, 10:36 AM

Doesn't every item of the list has a property checked?

like

List.listitem.item(X).checked??

The code you wrote before was a great approach, what was the problem with it?

Hughesie78 · March 19th, 2009, 11:14 AM

Ok here is my code below:

situation: when I select any of the items 1-9, its fine, when I selected item 0 all the others are unselected.. this is fine.
PROBLEM: once this happens and item zero is the only one selected, I try to selected an item in 1-9 but it will not allow me until manually unselected item zero.
What I want to happen is that once I reclick item 1 say, that this will allow me and will unselected item zero at same time.
Does this make sense
So basically half of it is working
If lstStore.Items.Count >= 0 Then

For i = 0 To lstStore.Items.Count - 1

If lstStore.GetSelected(i) = TrueAnd i <> 0 Then

Me.lstStore.SetSelected(0, False)
ElseIf lstStore.GetSelected(i) = TrueAnd i = 0 Then
Me.lstStore.ClearSelected()
Me.lstStore.SelectedIndex = 0

EndIf

Next i

gbianchi · March 19th, 2009, 11:23 AM

And now we have a real problem :)

Ok, you are rigth, because you are always looking if the first item is checked.

So a solution could be have and internal boolean variable that work something like this:

At first it false. When you checked 0, convert it to true and deselect all.
when you enter the procedure again, check if the value is true and that 0 item is selected, if that happens, this is a case when the user pressed another checkbox.
if the value is true but item 0 is unchecked, then put value to false and don't do anything else..

Also some notes.

a For that does something different for the first item is useless. Better start the for at 1, and do the work for the first item before the for.
Also
if something = true then...
is the same as
if something then
because something is a boolean by itself ;)