The application context is a class I have placed in the root of my project. It contain a static property called Current used to gain easy access to it’s properties. It implements INotifyPropertyChanged so it’s possible to notify if a property is changed. In this sample I have added a bool property called IsAuthenticated.
To actually use the application context in bindings in the xaml it’s necessary to point to a resource that points to the class. In the sample below I have called the namespace root and called the resource Context. Furthermore I have added a resource to a bool to visibility converter from the Quebec framework and called it BoolToVisibilityConverter.
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Courtesy:http://xamlgeek.net/2011/01/08/show-ui-element-based-on-authentication/