Propertychange event not triggered for enum type in MVVM binding

Hi,

I have created simple MVVM sample with two buttons named "Width" (enumeration binding) and "150" (integer binding) in WPF. The "150" button is properly triggered the ZoomPropertyChanged in ZoomMode.cs class. But the ZoomModePropertyChanged in ZoomMode.cs class is not triggered when the "Width" button is clicked.

Steps to reproduce the issue:

1.Download the sample

https://expirebox.com/download/37fc1d7a1e1fb061e7a5369672f5b747.html

2.Place the break point in ZoomModePropertyChanged and ZoomPropertyChanged event handler in ZoomMode.cs class file.

3.Run the sample and click the button "150"(ZoomPropertyChanged is triggered)

4.Now click the button "Width"(ZoomModePropertyChanged is not triggered)

Why ZoomModePropertyChanged is not triggered?

Kindly let me know if im doing any thing wrong.

Regards,