protected override void OnPreviewGotKeyboardFocus(KeyboardFocusChangedEventArgs e)
{
base.OnPreviewGotKeyboardFocus(e);
if (this.AutoSelectBehavior == AutoSelectBehavior.OnFocus)
{
// If the focus was not in one of our child ( or popup ), we select all the text.
if (!TreeHelper.IsDescendantOf(e.OldFocus as DependencyObject, this))
{
this.SelectAll();
}
}
}
/// <summary>
/// Returns true if the specified element is a child of parent somewhere in the visual
/// tree. This method will work for Visual, FrameworkElement and FrameworkContentElement.
/// </summary>
/// <param name="element">The element that is potentially a child of the specified parent.</param>
/// <param name="parent">The element that is potentially a parent of the specified element.</param>
public static bool IsDescendantOf(DependencyObject element, DependencyObject parent)
{
return(TreeHelper.IsDescendantOf(element, parent, true));
}