如何在WPF上使用Dispatcher或BackroundWorker以及自定义StatusBar控件

In my application I realized a custom statusbar control. It has progressbar, statusTextBox etc. Other modules could get the instance of that class with MEF, and bind their data in his elements with methods and properties. The problem is that the View of my statusbar updates only after some operation has finished. Here is a code example:In my application I realized a custom statusbar