/// <summary>
/// Called when HeaderProperty is invalidated on "d."
/// </summary>
private static void OnHeaderChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
HeaderedContentControl ctrl = (HeaderedContentControl)d;
ctrl.SetValue(HasHeaderPropertyKey, (e.NewValue != null) ? BooleanBoxes.TrueBox : BooleanBoxes.FalseBox);
ctrl.OnHeaderChanged(e.OldValue, e.NewValue);
}
/// <summary>
/// HeaderProperty property changed handler.
/// </summary>
/// <param name="d">HeaderedContentControl whose Header property is changed.</param>
/// <param name="e">DependencyPropertyChangedEventArgs, which contains the old and new value.</param>
private static void OnHeaderPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
HeaderedContentControl ctrl = (HeaderedContentControl)d;
ctrl.OnHeaderChanged(e.OldValue, e.NewValue);
}