Question

I have a custom control in which I created a custom DependencyProperty called TheObject that can contain a generic object.

<comp:MyControl TheObject="{Binding Country}" />

Sometimes, I need to set the TheObject internally (by code, internally to the control).

I did something like this:

this.TheObject = new Country();

But I realized that it is causing the loss of the DataBinding and the control becomes not responding to data changes.
What I really want is that this new object remains attached to the existing DataBinding of the property.

Answer 1

Use SetCurrentValue:

This method is used by a component that programmatically sets the value of one of its own properties without disabling an application’s declared use of the property. The SetCurrentValue method changes the effective value of the property, but existing triggers, data bindings, and styles will continue to work.

this.SetCurrentValue(TheObjectProperty, new Country());