WPF Combo Box doesn't rollup until the event is processed.

[jennyk]

I have a small program which has a combobox and a text box on it.

In the combo box selection changed event, i have something like this

private void comboBox1_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
System.Threading.Thread.Sleep(10000);
textBox1.Text = "Something";

}

When ever i select something from the combox box, it waits 10sec and displays "Something" in textBox1. But the problem here is until 10sec, the combobox stay open, then displays text and then rollup. That means it is waiting until selectionchanged event to completed to rollup.

How can i make the combobox rollup(or close) ones a value is selected.

I am attaching a picture, which shows the rolldown of combobox(If what i said above is not clear)

Thank You for any help!!!!