Dependencyproperty binding not updating
This brings us to the root of the problem: we can’t debug dependency properties with our normal techniques,because they are updated with methods we have no insight into. Property metadata allows you to define some additional behaviors for your dependency property.
Among these is the concept of a property changed callback; that is, a method that will run each time your dependency property is updated. I know I wouldn’t want to be littering my code with snippets like this, nor would I be very excited about manually editing that format string in every instance.
I think this is the case with most powerful frameworks.
You invoke a few lines of magic, and the tool takes care of all the low level wiring code for you.
We can implement a helper class with an Attached Property for this purpose: We use a Check Box in this example only for illustration purposes.
You can easily replace it with your view model, which is not possible without involving our helper class.
A minus sign (-) indicates that a sign character precedes only negative exponents when you implement Dependency Properties.
Note that the sample approach can be used in Silverlight.
For instance, review the Use Event To Command with Appointment events ticket.
When a complex chain of bound data isn’t working correctly, it can often be difficult to tell where the system is breaking down.
To understand why this is, first we need to know a little bit about how dependency properties work in WPF.