deselecting items in listbox after certain other item choosen.

Hughesie78 · March 20th, 2009, 06:33 AM

ok, here is what ive done. now, it works fine, until i select 3 from items 1-9, and want to select back to item 0, its not setting my boolean to true.

Dim bStore As Boolean
bStore = False
'determine what has been selected and give it boolean
If lstStore.Items.Count >= 0 Then

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

If bStore = True And lstStore.GetSelected(i) = True And i <> 0 Then
bStore = False
ElseIf bStore = True And lstStore.GetSelected(i) = True And i = 0 Then
bStore = True
ElseIf bStore = False Then
If lstStore.GetSelected(i) = True And i = 0 Then
bStore = True
ElseIf lstStore.GetSelected(i) = True And lstStore.GetSelected(0) = True Then
bStore = True
ElseIf lstStore.GetSelected(i) = True And lstStore.GetSelected(0) = True And i <> 0 Then
bStore = True
End If
Else
bStore = True
End If
Next i
'pass stores based on boolena bStore
If bStore = True Then
Me.lstStore.ClearSelected()
Me.lstStore.SetSelected(0, True)
Else
Me.lstStore.SetSelected(0, False)
End If
End If

gbianchi · March 20th, 2009, 08:09 AM

Bstore has to be at form level, not procedure level. nothing is good if you have it that way (since it will always take the value of item 0 selection, so you are not winning anything). The whole idea, is to know if the item was previously selected, or was selected in this change.
Also did you read the rest of the post?? you are still making the errors I pointed to you.

Hughesie78 · March 20th, 2009, 09:17 AM

hi

yes I read the rest of your post, I will make those changes, but first.. what can i do to make hte bstore at form level.. if u didnt guess already.. am Im a VB.net newbie!

gbianchi · March 20th, 2009, 09:25 AM

Well, if you can define a variable at procedure level, you can do it the same at form level (in this case, your form is a class). Just take it outside the procedure.. and read!, google is your best friend.

Hughesie78 · March 20th, 2009, 09:50 AM

ok.. have declared bStore now outside my onlclick 'PrivateSub lstStore_Click
still when i select any of 1-9 items, i cannot reslect item 0.

gbianchi · March 20th, 2009, 09:55 AM

mmm.. And did you change your code????

read my pseudo code and try to make it work. Your actual code don't work (not even do what is supposed to do. Why not try with adding some comments so you find out if you are doing what you are supposed to do. Also, debugging is a great way to find out what is happening.

Are you new to programming also?

Hughesie78 · March 20th, 2009, 10:01 AM

no didnt change. not sure exactly what to do.

I wouldnt say new, raw & new to OO would be more the truth, im a DB Developer.

gbianchi · March 20th, 2009, 01:21 PM

ok. This will do the trick, put a checkedlistbox on a form and add this...

Code:

    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        'add info to the listbox

        For i As Int16 = 0 To 9
            Me.CheckedListBox1.Items.Add(i, False)
        Next
    End Sub


    Private Sub CheckedListBox1_ItemCheck(ByVal sender As Object, ByVal e As System.Windows.Forms.ItemCheckEventArgs) Handles CheckedListBox1.ItemCheck
        If e.Index = 0 Then
            'has changed the first element
            If e.NewValue = CheckState.Checked Then
                'clear the rest of the list
                While CheckedListBox1.CheckedIndices.Count > 0
                    CheckedListBox1.SetItemCheckState(CheckedListBox1.CheckedIndices.Item(0), CheckState.Unchecked)
                End While
            End If
        Else
            'has changed the other elements
            'don't do anything
        End If

    End Sub

Hughesie78 · March 23rd, 2009, 06:50 AM

thanks a mil.
is there anyway this can be done by using only a list box, and not a checked list box? list box is the preffered choice.

Hughesie78 · March 23rd, 2009, 07:07 AM

also, when I use the code above, and i sected two Items between 1 & 9 i get a break error "An unhandled exception of type 'System.StackOverflowException' occurred in mscorlib.dll"