Essentially for our event to work we need the sender to be the shopping cart proxy and not the actual shopping cart.To do this we will need to extend one of version, but I’ll leave that as an exercise for the reader.Upon closer inspection I discovered that the object we were binding to was an delegate and you would think all is well.You of course would be wrong, here is what happens when the Shopping Cart raises a property changed event.It has a public property named Current, which returns a random number. When the value changes, the Property Changed event is raised so that the binding system will attempt to push that new value into a Text Block in the UI.The Text Block’s Text property is bound to the Current property on the Random Number Engine, and that binding is where we use the Update Threshold Converter to govern how often the data is pushed.I think the basic idea is that an entity in his system which is not “started” will be displayed as a “Start” button, and an entity which has already “started” will be displayed as a “Stop” button.Each button’s Command is set to a custom command to “start” or “stop” the entity, and the button’s Command Parameter is bound to the entity itself.
In this post, I will give you some tips on how you can debug your data bindings in WPF.Wouldn’t it be nice if you break into the debugger the instant you have a data binding error? NET Developer Group a few days ago, someone in the audience asked a question about the data binding system which piqued my interest. My problem involved a read only property that was not updated in the UI even though the property changed event was being raised.It worked fine when I first created the object, but after loading it at a later time the updates didn’t work anymore.