WinForms TreeView - how to manually "highlight" node (like it was clicked)

Question

I would need to know how to let the programatically selected node make graphically in the state "selected" like the user clicked on it. SelectedNode only makes this one internally selected. Thank you very much!

Answer 1

The reason it does not show as highlighted is due to the tree view not having focus. This is in a button click event on my test form:

TreeView1.SelectedNode = TreeView1.Nodes(2);
TreeView1.Focus();

Which highlights the node properly. if you remove the Focus(); call it doesn't highlight until you click into the tree view (anywhere in the tree view, not necessarily on to the node that you want to be selected).

Answer 2

TreeView1.SelectedNode.BackColor = SystemColors.HighlightText; // This will work

Above solutions will only set the focus on it but will not change the highlight view of it.

Answer 3

This works for me for .net 3.5: Set the treeview component's DrawMode property to: OwnerDrawAll Then in the DrawNode event write the following:

 if (((e.State & TreeNodeStates.Selected) != 0) && (!MyTreeView.Focused))
     e.Node.ForeColor = Color.Blue;
else
     e.DrawDefault = true;

And in the BeforeSelect event have:

if (MyTreeView.SelectedNode != null)
    MyTreeView.SelectedNode.ForeColor = Color.Black;
e.Node.ForeColor = Color.Blue;

Answer 4

Here is what I got to work:

void myProcedure()
{
  // Hookup a DrawMode Event Handler
  this.myTV.DrawNode += myTV_DrawNode;
  // Set DrawMode and HideSelection
  this.myTV.DrawMode = TreeViewDrawMode.OwnerDrawText;
  this.myTV.HideSelection = false;

  // Make sure the TreeView has Focus
  this.myTV.Focus();
  // Make sure the TreeView is Selected
  this.myTV.Select();
  // If the TreeView has a Node, I want to select the first Node to demonstrate.
  if (this.myTV.Nodes.Count > 0)
  {
    // Make sure the node is visible
    this.myTV.Nodes[0].EnsureVisible();
    // Make sure the Node is Selected
    this.myTV.SelectedNode = myTV.Nodes[0];
  }
  // Make sure the SelectedNode IS the Node that we programmatically want to select.
  textBox1.Text = this.myTV.SelectedNode.Text;
  // if we display sanityCheck1 string, it actually is the correct node.text
  // Make sure .NET runtime knows the Node is selected
  textBox1.Text += "  is Selected = " + this.myTV.SelectedNode.IsSelected.ToString();
}

Following up: laalto answered the How to HighLight the TreeView.Node. The following code in the DrawNode Event Handler, from samball's answer, properly highlights the TreeView.Node based on its Selected State.

private void myTV_DrawNode(object sender, DrawTreeNodeEventArgs e)
{
  // first, let .NET draw the Node with its defaults
  e.DrawDefault = true;
  // Now update the highlighting or not
  if (e.State == TreeNodeStates.Selected)
  {
    e.Node.BackColor = SystemColors.Highlight;
    e.Node.ForeColor = SystemColors.HighlightText;
  }
  else
  {
    e.Node.BackColor = ((TreeView)sender).BackColor;
    e.Node.ForeColor = ((TreeView)sender).ForeColor;
  }
}

Platform = C# .NET 4.5 in Windows 10, Visual Studio 2015

Answer 5

TreeView1.SelectedNode = TreeView1.Nodes(2);
this.ActiveControl = TreeView1;

This works for me (.net 4.7)

Answer 6

I don't know if it helps you or not but check the taborder of the the page and make sure that the tree view control has tab order of 0

Answer 7

I had an similar issue and wanted to have a TreeView node selected (highlighted) on form load. Maybe someone has the same problem, too.

I first tried Pondidum's solution. Without success. But then I found the solution in another thread: Simply set the TabIndex of the TreeView to 0. In that case you don't need to set the focus. Just choose the node that should be selected by using SelectedNode and set the TabIndex. That's it.

Answer 8

The underlying Win32 control supports this (think it's TVIS_DROPHILITED), but I can't see the same functionality exposed through the TreeView control.

As theraneman says, you could fake it with the TreeNode.ForeColor and BackColor properties...

Answer 9

Not sure, but can you not change the background color of that node?