C#

Dave Kreskowiak wrote:

That's because the UI thread has to handle adding those items to the ListView. it cannot be done from another thread because you can only maniplute a control on the thread that created it.

You can, however, add each item tot he ListView, one a few at time, from a background thread, by Invoking a method on the UI thread to add just a few items at a time.

' Because we run our routine that gets the selected class's properties on a background thread using the
' BackgroundWorker component, we can't update our listview directly using this thread, if we try, we get
' a cross-threading exception; our listview was created on the program's main thread and can't be changed
' directly by our background thread.

' To get round this little problem, we create delegate routines and then call the listview control's
' invoke method which uses the delegated routine to update the listview control on the main thread.

Private Delegate Sub AddItem(ByVal lv As ListView, ByVal lvi As ListViewItem)

Private Shared Sub AddListViewItem(ByVal listViewCtrl As ListView, ByVal lvi As ListViewItem)
           listViewCtrl.Items.Add(lvi)
       End Sub

listViewCtrl.Invoke(New AddItem(AddressOf AddListViewItem), New Object() {listViewCtrl, lvGroupItem})

Luc Pattyn wrote:

. it is wise to use AddRange rather than Add, and

Luc Pattyn wrote:

sometimes surround the entire operation with SuspendLayout/ResumeLayout