You can create ScaleFactor dependency property for your user control which internally bounds to the RadPdfViewer's ScaleFactor depencency property. This way the application can be bound to the new dependency property without having to know about Telerik's control internal existance.
I am attaching a sample project showing how to achieve the described above. A few words about this project:
- There is PdfViewerUserControl which has a RadPdfViewer in it.
- In code behind of this user control a new ScaleFactor dependency property is registered.
- In XAML the PdfViewerUserControl's ScaleFactor property in bounded to the child RadPdfViewer's dependency property.
- In MainWindow.xaml the user control is used and a textbox has its text property bounded to the ScaleFactor dependency property.
- Either by holding control and scrolling with the mouse wheel, or by using the "Zoom in" and "Zoom out" buttons you may change the ScaleFactor and this results in updating the text in the textbox.
I hope this helps. If you have any other questions or concerns do not hesitate to contact us again.
the Telerik team
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