刷新后聚焦TreeViewElement

Question

I have a Problem with focusing an TreeViewItem. I have a (little bit optimated) TreeView and refreshing the content. Visually the selected Item stays selected but logically it isn't. The Focus-Check at the beginning and at the end are not the same, but in my opinion they should.

Here is my Code (with all non-working refocusing things):

private void Refresh(string selectedContent)
{
    //Check out the focused element
    //Returns "System.Windows.Controls.TreeViewItem Header:<my selectedContent-Value>; Items.Count:0"
    MessageBox.Show(Keyboard.FocusedElement.ToString());

    var currentFocus = Keyboard.FocusedElement;
    tv.Refresh(); //this refreshes the treeview

    //Not working
    Keyboard.Focus(currentFocus);

    //Not working
    DependencyObject focusScope = FocusManager.GetFocusScope(currentFocus);
    FocusManager.SetFocusedElement(focusScope, currentFocus);

    //also not working
    currentFocus.Focus();

    //not working
    Keyboard.Focus(tv.TryFindNode(selectedContent)); //TryFindNode searches the node in the TreeView and returns it

    //not working
    tv.TryFindNode(selectedContent).Focus();

    //Check out the focused element
    //returns "TreeViewTesting.TreeViewTesting" (my class where I'm testing this issue)
    MessageBox.Show(Keyboard.FocusedElement.ToString());
}

What I don't understand is, that this works:

private void Refresh(string selectedContent)
{
    //Check out the focused element
    //Returns "System.Windows.Controls.TreeViewItem Header:<my selectedContent-Value>; Items.Count:0"
    MessageBox.Show(Keyboard.FocusedElement.ToString());

    tv.Refresh(); //this refreshes the treeview

    MessageBox.Show("I'm just a Message to show a messagebox");

    tv.TryFindNode(selectedContent).Focus();

    //Check out the focused element
    //Returns "System.Windows.Controls.TreeViewItem Header:<my selectedContent-Value>; Items.Count:0"
    MessageBox.Show(Keyboard.FocusedElement.ToString());
}

So, how do I that, what the Dummy-Messagebox is doing with the focus? Anyone has an Idea?

Answer 1

I have an application that manipulates other controls after selecting a TreeNode in a TreeView. When the process is done, the TreeNode is still selected but the TreeView has lost focus.

Based on Hunv's approach in their comments above, I found the following to produce the desired result (which is TreeView focused, TreeNode selected):

private void treeView_AfterSelect(object sender, TreeViewEventArgs e)
{
    ProcessMySelection();

    // give the app a chance to 'recover' and keep focus on the TreeView
    // i don't understand why this works -- is there a better way?
    Application.DoEvents()
}