Set focus on textbox in WPF

Question

How to set the focus on an TextBox element in WPF

I have this code:

txtCompanyID.Focusable = true;
txtCompanyID.Focus();

Answer 1

In Code behind you can achieve it only by doing this.

 private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            txtIndex.Focusable = true;
            txtIndex.Focus();
        }

Note: It wont work before window is loaded