private void AirfieldInfoButton_Checked(object sender, RoutedEventArgs e)
{
if (airfieldinfo == null)
{
airfieldinfo = new AirfieldInformationWindow(airfield, this);
}
airfieldinfo.Closed += Airfieldinfo_Closed;
airfieldinfo.Show();
}
private void Airfieldinfo_Closed(object sender, EventArgs e)
{
airfieldinfo = null;
}
