private bool AllowHandleKeyEvent(FocusNavigationDirection direction)
{
if (!IsSelected)
{
return(false);
}
DependencyObject currentFocus = Keyboard.FocusedElement as DependencyObject;
if (currentFocus != null && UIElementHelper.IsUIElementOrUIElement3D(currentFocus))
{
DependencyObject predict = UIElementHelper.PredictFocus(currentFocus, direction);
if (predict != currentFocus)
{
while (predict != null)
{
TreeViewItem item = predict as TreeViewItem;
if (item == this)
{
return(false); // There is a focusable item in the header
}
else if ((item != null) || (predict is TreeView))
{
return(true);
}
predict = VisualTreeHelper.GetParent(predict);
}
}
}
return(true);
}
