The code that I used to traverse the Visual Tree did not use the ApplyTemplate()
method for a FrameworkElement
in the tree and therefore cildren could not be found. In my situation the following code works:
/// <summary>
/// Looks for a child control within a parent by name
/// </summary>
public static DependencyObject FindChild(DependencyObject parent, string name)
{
// confirm parent and name are valid.
if (parent == null || string.IsNullOrEmpty(name)) return null;
if (parent is FrameworkElement && (parent as FrameworkElement).Name == name) return parent;
DependencyObject result = null;
if (parent is FrameworkElement) (parent as FrameworkElement).ApplyTemplate();
int childrenCount = VisualTreeHelper.GetChildrenCount(parent);
for (int i = 0; i < childrenCount; i++)
{
var child = VisualTreeHelper.GetChild(parent, i);
result = FindChild(child, name);
if (result != null) break;
}
return result;
}
/// <summary>
/// Looks for a child control within a parent by type
/// </summary>
public static T FindChild<T>(DependencyObject parent)
where T : DependencyObject
{
// confirm parent is valid.
if (parent == null) return null;
if (parent is T) return parent as T;
DependencyObject foundChild = null;
if (parent is FrameworkElement) (parent as FrameworkElement).ApplyTemplate();
int childrenCount = VisualTreeHelper.GetChildrenCount(parent);
for (int i = 0; i < childrenCount; i++)
{
var child = VisualTreeHelper.GetChild(parent, i);
foundChild = FindChild<T>(child);
if (foundChild != null) break;
}
return foundChild as T;
}
Thanks for the comments of "dev hedgehog" for pointing that out (I missed it).
I will not use this approach in production code, it has to be done with databinding like "HighCore" commented.
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