Get the UserControl from DataTemplate

Question

I have a DataTemplate in which i have simply used a UserControl.

DataTemplate x:Key="SampleDataTemplate">
        <controls1:UserControl1>

        </controls1:UserControl1>
</DataTemplate>

This DataTemplate is used in TransitionControl.ContentTemplate Now I want the UserControl1 Object in the c# CodeBehind.

Something Like this

TransitionControl.ContentTemplate this DataTemplate will give me UserControl1 object.

Answer 1

You could use VisualTreeHelper's GetChildrenCount and GetChild methods to get to the control that you need. Here's a method that will help (tweak it if necessary):

private List<T> FindChildren<T>(DependencyObject startNode, List<T> results = null) where T : DependencyObject {
    if (results == null) results = new List<T>();

    int count = VisualTreeHelper.GetChildrenCount(startNode);
    for (int i = 0; i < count; i++) {
        DependencyObject current = VisualTreeHelper.GetChild(startNode, i);
        if ((current.GetType()).Equals(typeof(T)) || (current.GetType().GetTypeInfo().IsSubclassOf(typeof(T)))) {
            T realType = (T)current;
            results.Add(realType);
        }
        FindChildren<T>(current, results);
    }

    return results;
}

So, all you need to do is call FindChildren<UserControl1>(MyTransitionControlInstance) and you'll get get the instance of the UserControl1 control (well, all of the instances, if there are more).

P.S. It really is a good idea to tweak the method to just look for one element, and not for all of them, if you need just one which seems to be the case.