Issue: Activating other window on closed event - wpf

Question

I have some window, which can have many instances opened in single application.
I track all of them in a static dictionary.
The window must be closed when escape pressed if the window is active. And if the window is closed through escape i need activate other window, stored in a dictionary if there is one. I also need to consider current windows z-order and activate the top most of them, but for now it doesn`t matter.
So, when i have some windows opened and try to close them subsequently pressing escape what i get is that at some moment all of the windows left are closed simultaneously.
Here is the code example:
namespace WpfApplication1
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private int _count;
private void Button_Click(object sender, RoutedEventArgs e)
{
Window1.Run(this, ++_count);
}
}
/// <summary>
/// Interaction logic for Window1.xaml
/// </summary>
public partial class Window1 : Window
{
private static Dictionary<int, Window1> _opened =
new Dictionary<int, Window1>();
private int _key;
public Window1()
{
InitializeComponent();
KeyDown += OnKeyDown;
}
private void OnKeyDown(object sender, KeyEventArgs ea)
{
if (ea.Key == Key.Escape)
{
Close();
}
}
public static void Run(Window owner, int key)
{
Window1 w = null;
if (_opened.TryGetValue(key, out w))
{
w.Activate();
}
else
{
w = new Window1{_key = key};
w.Closed += (s, e) =>
{
var win = s as Window1;
_opened.Remove(win._key);
if (_opened.Count > 0)
{
_opened.First().Value.Activate();
}
};
_opened.Add(key, w);
w.Show();
}
}
}
}
Update#1
Thanks to Potecaru Tudor, he found another solution:
The solution I found was to set e.Handled = true in your KeyDown
handler after calling Close()
Solution Code:
private void OnKeyDown(object sender, KeyEventArgs ea)
{
if (ea.Key == Key.Escape)
{
ea.Handled = true;
Close();
}
}
Update#2
And here is another, not so elegant solution, just for the record
...
_opened.Remove(win._key);
if (_opened.Count > 0)
{
// i suppose here is the error hidden
var w2 = _opened.First().Value;
w2.Dispatcher.BeginInvoke(new Action(() => w2.Activate()));
}
...

Answer 1

I tried to reproduce your issue with no success, the windows are closing just fine one by one. You could try calling the Close() method only if Window.IsActive property is set on true.
EDIT I managed to reproduce your issue.
The solution I found was to set e.Handled = true in your KeyDown handler after calling Close()
I suppose the issue is that the windows become active one after another before the first one gets to be closed, so they also received the KeyDown event firing. The weird thing is it only happens in my sample for the first windows you're opening. After you're closing all of them and start opening others this will not reproduce.

Answer 2

Only way i have found is to delay next window activation, like this:
...
_opened.Remove(win._key);
if (_opened.Count > 0)
{
// i suppose here is the error hidden
var w2 = _opened.First().Value;
w2.Dispatcher.BeginInvoke(new Action(() => w2.Activate()));
}
...
Any other suggestions would be appreciated! Thank you!