You're actually creating a user control; and not a "custom control". The "simplest" way to create a user control is to add properties {get;set;} to the UC in the .cs; bind the controls in the .xaml to the properties in the .cs; and implement INotifyPropertyChanged (which for a "few" controls, can be issued with "no contol name" without any hit on performance). The DataContext of the UC is the UC; i.e. "this". Any time there is new data, you load the properties and call "property changed" which updates the UI. If it's a two-way UI, data moves to the properties and events on the controls get invoked (e.g. text changed). That's the pattern, and most everything else has a "smell". X| :-\ Anything else that happens is a function of what events the user control wants to "surface" (e.g. a request queued to an observable collection or file watcher).
"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I
