[RESOLVED] Treeview.ExpandAll - When is it done?

[Radjesh Klauke]

Ola,

I have loaded a treeview with files and folders. When I click on a folder which has a lot of subfolders and files this can take a while. Which event do I need to use to show a messagbox that the "expanding" is done? The is the same when I use Treeview.ExpandAll().

Thanks in advance.

[jmcilhinney]

Are you talking about the AfterExpand event?

[Radjesh Klauke]

Thanks, but no.
Example:
- Treeview is loaded with files and folders;
- When I click on a [+] to expand a folder I want to show: "expanding folder" on a label and when it is done expanding the folder: "done".

[ForumAccount]

Thanks, but no.
Example:
- Treeview is loaded with files and folders;
- When I click on a [+] to expand a folder I want to show: "expanding folder" on a label and when it is done expanding the folder: "done".

Actually, yes. You are looking for the BeforeExpand and AfterExpand events. This is a simulation of expanding a TreeView that takes time to process:

Public Class Form1
 
    '//fields
    Private previousText As String
 
    '//event handlers
    Private Sub TreeView1_AfterExpand(ByVal sender As Object, _
                                      ByVal e As TreeViewEventArgs) _
                                      Handles TreeView1.AfterExpand
        e.Node.Text = Me.previousText
 
        '//you could do this, although you might just
        '//want to set the text back as it is annoying
 
        '//MessageBox.Show("Done")
    End Sub
 
    Private Sub TreeView1_BeforeExpand(ByVal sender As Object, _
                                       ByVal e As TreeViewCancelEventArgs) _
                                       Handles TreeView1.BeforeExpand
        Me.previousText = e.Node.Text
        e.Node.Text = "Expanding..."
        Application.DoEvents()
        Threading.Thread.Sleep(750)
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, _
                              ByVal e As System.EventArgs) _
                              Handles Button1.Click
        '//make sure you add some nodes
        Me.TreeView1.Nodes(0).ExpandAll()
    End Sub
 
End Class

[Radjesh Klauke]

Thanks ForumAccount. +REP