Public Function FindCommonVisualAncestor ( _
    otherVisual As DependencyObject _
) As DependencyObject

Dim instance As Visual
Dim otherVisual As DependencyObject
Dim returnValue As DependencyObject

returnValue = instance.FindCommonVisualAncestor(otherVisual)

public DependencyObject FindCommonVisualAncestor(
    DependencyObject otherVisual
)

public:
DependencyObject^ FindCommonVisualAncestor(
    DependencyObject^ otherVisual
)

public function FindCommonVisualAncestor(
    otherVisual : DependencyObject
) : DependencyObject

You cannot use methods in XAML.