Question

I am transfering FrameworkElement from StackPanel on WPF Page to programmatically created StackPanel. At a certain point I need to refresh bindings and get property values.

At this point FrameworkElement.DataContext has correct value and BindingExpression.Status==BindingStatus.Unattached for all binding expressions. I execute BindingExpression.UpdateTarget, but property values are empty.

I found source code for BindingExpression.UpdateTarget():

    public override void UpdateTarget() 
    {
        if (Status == BindingStatus.Detached) 
            throw new InvalidOperationException(SR.Get(SRID.BindingExpressionIsDetached)); 

        if (Worker != null) 
        {
            Worker.RefreshValue();  // calls TransferValue
        }
    } 

Worker gets instance in internal override void BindingExpression.Activate(). Also inside Activate() BindingExpression.Status set to BindingStatus.Active.

How can I programmatically initiate execution for BindingExpression.Activate() and make UpdateTarget after that?

Update

Solution here (thanks, Olli):

public  void UpdateAllBindingTargets( DependencyObject obj)
    {

        FrameworkElement visualBlock = obj as FrameworkElement;
        if (visualBlock==null)
            return;
        if (visualBlock.DataContext==null)
            return;
        Object objDataContext = visualBlock.DataContext;

        IEnumerable<KeyValuePair<DependencyProperty, BindingExpression>> allElementBinding = GetAllBindings(obj);
        foreach (KeyValuePair<DependencyProperty, BindingExpression> bindingInfo in allElementBinding)
        {
            BindingOperations.ClearBinding(obj, bindingInfo.Key);

            Binding myBinding = new Binding(bindingInfo.Value.ParentBinding.Path.Path);
            myBinding.Source = objDataContext;
            visualBlock.SetBinding(bindingInfo.Key, myBinding);
            BindingOperations.GetBindingExpression(visualBlock, bindingInfo.Key).UpdateTarget();

        }

    }

where getting all bindings for object:

public  IEnumerable<KeyValuePair<DependencyProperty, BindingExpression>> GetAllBindings( DependencyObject obj)
    {
        var stack = new Stack<DependencyObject>();

        stack.Push(obj);

        while (stack.Count > 0)
        {
            var cur = stack.Pop();
            var lve = cur.GetLocalValueEnumerator();

            while (lve.MoveNext())
                if (BindingOperations.IsDataBound(cur, lve.Current.Property))
                {
                    KeyValuePair<DependencyProperty,BindingExpression> result=new KeyValuePair<DependencyProperty, BindingExpression>(lve.Current.Property,lve.Current.Value as BindingExpression);
                    yield return result;
                }

            int count = VisualTreeHelper.GetChildrenCount(cur);
            for (int i = 0; i < count; ++i)
            {
                var child = VisualTreeHelper.GetChild(cur, i);
                if (child is FrameworkElement)
                    stack.Push(child);
            }
        }
    }

Answer 1

You can programmatically create a new binding, which should do the trick.

http://msdn.microsoft.com/en-us/library/ms752347.aspx#creating_a_binding

Example from the MSDN page

MyData myDataObject = new MyData(DateTime.Now);      
Binding myBinding = new Binding("MyDataProperty");
myBinding.Source = myDataObject;
myText.SetBinding(TextBlock.TextProperty, myBinding);