private void cboColor_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
if (cboColor.Items.Count > 0 && ((ComboBoxItem)cboColor.SelectedItem).Content != null)
{
if (((ComboBoxItem)cboColor.SelectedItem).Content.ToString() == "Blue")
drawingPane.DefaultDrawingAttributes.Color = Colors.Blue;
else if (((ComboBoxItem)cboColor.SelectedItem).Content.ToString() == "Green")
drawingPane.DefaultDrawingAttributes.Color = Colors.Green;
else if (((ComboBoxItem)cboColor.SelectedItem).Content.ToString() == "Red")
drawingPane.DefaultDrawingAttributes.Color = Colors.Red;
else if (((ComboBoxItem)cboColor.SelectedItem).Content.ToString() == "Yellow")
drawingPane.DefaultDrawingAttributes.Color = Colors.Yellow;
else if (((ComboBoxItem)cboColor.SelectedItem).Content.ToString() == "Black")
drawingPane.DefaultDrawingAttributes.Color = Colors.Black;
}
}