Actually, judging by the information you have provided, it seems like you wouldn't need to set the ContentViewDisplayMode at all. Can you please confirm that what you have as a setup is one page ("Home") with one news widget on it displaying a section of news, and another page ("NewsDetail") which also has one news widget, which should display a selection of news if now querystring parameter is included int he URL or a single news item in details mode, if a news item from "Home" is clicked? If that's correct, than this falls in the default behavior of the news widget - it has its ContentViewDisplayMode property set to automatic by default, and if a request from another news widget is made to a page which contains a news widget, it will automatically switch to Details, otherwise it will be in master and display a selection of news. Setting ContentViewDisplayMode is useful when you have two ContentView widgets (e.g. News) on the same page, as this would allow you to control how they react to passing querystring parameters in the URL of the same page.
Please do not hesitate to let me know if the functionality that you're trying to achieve differs from what I've described above.
the Telerik team
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