protected abstract void OnUpdate(
	TimeSpan deltaTime
)

Protected MustOverride Sub OnUpdate ( 
	deltaTime As TimeSpan
)

protected:
virtual void OnUpdate(
	TimeSpan deltaTime
) abstract

abstract OnUpdate : 
        deltaTime : TimeSpan -> unit 

This method is automatically called by Update(TimeSpan), but only if the screen is visible (see IsVisible). Derived classes can override this method to update the state of the screen, for example, to advance time dependent animations.