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wpftreeviewunselect

unselecting and reselecting a TreeViewItem in a TreeView


I've got the following problem:

In my TreeView i added unselect functionality by calling my own deselect()-method when the user clicks the TreeView but not a TreeViewItem. Here is my TreeView method:

public void deselectAll()
{
    TreeViewItem item = SelectedItem as TreeViewItem;
    if (item != null)
    {
        this.Focus();
        item.IsSelected = false;
    }
}

My problem is, that i can't reselect a TreeViewItem after i unselected it. I've read, that focusing the TreeView itself should solve this problem, but it's not. It also doesn't matter if i put the 'Focus()' before or after the 'IsSelected = false'.

Does anyone has an idea why this is not working? Any thoughts would be appreciated.


Solution

  • after you set item.IsSelected = false; you have to call .Focus() for your treeview.

            <TreeView MouseLeftButtonDown="TreeView_MouseLeftButtonDown">
                <TreeViewItem Header="Employee1">
                    <TreeViewItem Header="Jesper"/>
                    <TreeViewItem Header="Aaberg"/>
                    <TreeViewItem Header="12345"/>
                </TreeViewItem>
                <TreeViewItem Header="Employee2">
                    <TreeViewItem Header="Dominik"/>
                    <TreeViewItem Header="Paiha"/>
                    <TreeViewItem Header="98765"/>
                </TreeViewItem>
            </TreeView>
    
        private void TreeView_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
        {
            var tv = sender as TreeView;
    
            if (tv != null)
            {
                var item = (TreeViewItem)tv.SelectedItem;
                item.IsSelected = false;
                tv.Focus();
            }
        }
    

    you wrote focus() dont solve your problem. where do you call your deselectAll()?

    as a workaround you can use the MouseLeftDown to set an item as selected.

    ps: dont forget to mark an answer as an anwser.