listview

listview

• ureyes84

  OK My thought is that your probably trying to address sub items which you havent created for the record.

  I have a little example here. When you click button1 it sets up the listview and adds data for 2 records. You are adding the subitems to a collection of the listviewitem. So if you have 3 subitems then you can refer to them.

  So in the second record being added you will notice it works - now comment out those initial .SubItems.Add("") Statements and you will notice that the x.SubItems(0).Text = "New1" lines will now fail.

  Why Because they are referring to items which do not exist in the subitems collection. You need to look at this as a collection and not an array.

  I think you will need to look at what items you are actually populating in the listview.

  The second button will display the contents of a specified item. In this case the 1st record which has all 4 columns populated it will work. Now with those commented out subitems commented so it is only populating the item and no subitems and change the line to MsgBox(ListView1.Items.Item(1).SubItems.Item(2).Text) and this will now fail as there are no subitems for this record now.

  Hope this helps and I'm certain that this is what your issue is.

  
  Public Class Form1

  Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
  '//Setup the Listview
  Me.ListView1.View = View.Details
  Me.ListView1.Columns.Add("test1")
  Me.ListView1.Columns.Add("test2")
  Me.ListView1.Columns.Add("test3")
  Me.ListView1.Columns.Add("test4")

  '//Add an Item
  Dim x As New ListViewItem
  With x
  .Text = "Test"
  .SubItems.Add("Test col2")
  .SubItems.Add("Test col3")
  .SubItems.Add("Test col4")
  End With
  ListView1.Items.Add(x)

  
  '//Set using the blank template
  x = New ListViewItem
  With x
  .Text = "Second Record"
  .SubItems.Add("")
  .SubItems.Add("")
  .SubItems.Add("")
  End With
  ListView1.Items.Add(x)

  '//Update those subitems
  With ListView1.Items(1)
  x.SubItems(0).Text = "New1"
  x.SubItems(1).Text = "New2"
  x.SubItems(2).Text = "New3"
  x.SubItems(3).Text = "New4"
  End With

  End Sub

  
  Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
  MsgBox(ListView1.Items.Item(0).SubItems.Item(2).Text)
  End Sub
  End Class

  
  

• apat

  in my case

  MsgBox(ListView1.Items.Item(0).SubItems.Item(2).Text)
  
  is referring to 1st row - column 3

  MsgBox(ListView1.Items.Item(1).SubItems.Item(2).Text)

  is referring to 2st row - column 3

  But you must have all the subitems populated to refer to them by index. You cant just say row 2 column 3. You must have populated at least to items and on that 2nd item you must have populated at least 2 subitems. If you had populated a 2nd item and only 1 subitem and tried to refer to 2nd row , column 3 then you will get the error.

  This is not a grid - it is a means of displaying collections of items, subitems. You need to ensure the subitems are populated before you can refer to them.

  
  

  
  

• Greg Johnson

  Acually this is weird. Because I was using subItems as populating each different column not subitems in one column. Thats the weird. Thing. OOHHHH. I think I get it. All I want to do is change an already set text under one column on a certain row. As you can see in my code above thats what I was trying to do with the subitems. So how do I just change text on a certain row under a certain column.
  
  

• KoKoNassar

  The behaviour your describing sounds correct and by design that is the form load doesnt complete until all code within the form load event is run.

  The following article describes the firing order of the form events and a little bit about there unpredictable firing order and ways around this.

  http://www.knowdotnet.com/articles/eventfiringorder.html

  Hopefully this will help.

  
  

• john holland

  Thanks that help!
  
  Hey I have another problem...not pertaining to this subject.... I'm editing some text in my listview. I have 4 columns and I need to edit the 4 one or vb reads it as 3. (1-4|0-3) But when I edit the '3' one, and it gives me the an error saying that 3 is not a vaild index. I've tryed editing the 2 and 1 and 0 one and it works fine. but the 3 one always gives me an error. I've even tryed to add another column and still got an error. Here is the line that gives me the error.
  
  ListView1.Items.Item(num2).SubItems.Item(3).Text = FormatSize(num)
  
  This should sent the final format style (String) to the 4 column at 'num2' row. This line above it works just fine.
  
  ListView1.Items.Item(num2).SubItems.Item(2).Text = ""
  
  Can anyone figure out whats wrong Do I need to explain more
  
  

• Steve Nye

  Thanks that makes things more clear!
  
  
• listview