/// <summary>
/// Called when IParallaxSource changes
/// </summary>
private void OnSourceChanged(View oldSource, View newSource)
{
if (m_parallaxSourceView != null)
{
m_parallaxSourceView.OffsetChanged -= OnSourceOffsetChanged;
m_parallaxSourceView = null;
}
if (newSource is IParallaxSource)
{
m_parallaxSourceView = newSource as IParallaxSource;
m_parallaxSourceView.OffsetChanged += OnSourceOffsetChanged;
}
else
{
m_parallaxSourceView = ParallaxLayout.FindParallaxSourceRecursive(newSource);
if (m_parallaxSourceView != null)
{
m_parallaxSourceView.OffsetChanged += OnSourceOffsetChanged;
}
}
if (m_parallaxSourceView != null)
{
OnSourceOffsetChanged(m_parallaxSourceView.HorizontalOffset, m_parallaxSourceView.VerticalOffset);
}
}
/// <summary>
/// Called when source changes. If the source element is not a implementing IParallaxSource, the XAML tree is walked
/// starting at the source element to find an embedded IParallaxSource element.
/// </summary>
private void OnSourceChanged(View oldSource, View newSource)
{
if (m_parallaxSourceView != null)
{
m_parallaxSourceView.OffsetChanged -= OnSourceOffsetChanged;
}
if (newSource is IParallaxSource)
{
m_parallaxSourceView = newSource as IParallaxSource;
m_parallaxSourceView.OffsetChanged += OnSourceOffsetChanged;
}
else
{
m_parallaxSourceView = FindParallaxSourceRecursive(newSource);
if (m_parallaxSourceView != null)
{
m_parallaxSourceView.OffsetChanged += OnSourceOffsetChanged;
}
}
}
/// <summary>
/// Find IParallaxSource child using recursion
/// </summary>
public static IParallaxSource FindParallaxSourceRecursive(View view)
{
if (view is IParallaxSource)
{
return(view as IParallaxSource);
}
else if (view is ILayoutController)
{
ILayoutController layout = view as ILayoutController;
foreach (View child in layout.Children)
{
IParallaxSource source = FindParallaxSourceRecursive(child);
if (source != null)
{
return(source);
}
}
}
return(null);
}
