internal static DependencyObject GetUIParentCore(DependencyObject o)
{
UIElement e = o as UIElement;
if (e != null)
{
return(e.GetUIParentCore());
}
else
{
ContentElement ce = o as ContentElement;
if (ce != null)
{
return(ce.GetUIParentCore());
}
else
{
UIElement3D e3D = o as UIElement3D;
if (e3D != null)
{
return(e3D.GetUIParentCore());
}
}
return(null);
}
}
internal static DependencyObject GetUIParent(DependencyObject child, bool continuePastVisualTree)
{
DependencyObject parent = null;
DependencyObject myParent = null;
// Try to find a UIElement parent in the visual ancestry.
if (child is Visual)
{
myParent = ((Visual)child).InternalVisualParent;
}
else
{
myParent = ((Visual3D)child).InternalVisualParent;
}
parent = InputElement.GetContainingUIElement(myParent) as DependencyObject;
// If there was no UIElement parent in the visual ancestry,
// check along the logical branch.
if (parent == null && continuePastVisualTree)
{
UIElement childAsUIElement = child as UIElement;
if (childAsUIElement != null)
{
parent = InputElement.GetContainingInputElement(childAsUIElement.GetUIParentCore()) as DependencyObject;
}
else
{
UIElement3D childAsUIElement3D = child as UIElement3D;
if (childAsUIElement3D != null)
{
parent = InputElement.GetContainingInputElement(childAsUIElement3D.GetUIParentCore()) as DependencyObject;
}
}
}
return(parent);
}
// Walk up the parent chain to find the closest element with IsFocusScope=true
private static DependencyObject _GetFocusScope(DependencyObject d)
{
if (d == null)
{
return(null);
}
if ((bool)d.GetValue(IsFocusScopeProperty))
{
return(d);
}
// Step 1: Walk up the logical tree
UIElement uiElement = d as UIElement;
if (uiElement != null)
{
DependencyObject logicalParent = uiElement.GetUIParentCore();
if (logicalParent != null)
{
return(GetFocusScope(logicalParent));
}
}
else
{
ContentElement ce = d as ContentElement;
if (ce != null)
{
DependencyObject logicalParent = ce.GetUIParent(true);
if (logicalParent != null)
{
return(_GetFocusScope(logicalParent));
}
}
else
{
UIElement3D uiElement3D = d as UIElement3D;
if (uiElement3D != null)
{
DependencyObject logicalParent = uiElement3D.GetUIParentCore();
if (logicalParent != null)
{
return(GetFocusScope(logicalParent));
}
}
}
}
// Step 2: Walk up the visual tree
if (d is Visual || d is Visual3D)
{
DependencyObject visualParent = VisualTreeHelper.GetParent(d);
if (visualParent != null)
{
return(_GetFocusScope(visualParent));
}
}
// If visual and logical parent is null - then the element is implicit focus scope
return(d);
}