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Xamarin.Forms: making the switch control MVVM compliant

The switch control out of the Xamarin.Forms toolbox does not appear to be MVVM compliant. That means that its toggle (as a result of a UI tap) changes the state of the switch w/o validating or asking the Model (via the ViewModel) if it should change its state. I tried handling a "toggling" event or subclassing the switch but was unable to find a OOP solution to this problem. Instead I disabled the control and handled the ItemSelected event on the listView which first validates and then changes the state of the IsToggledProperty binding property. The disadvantage of incorrectly using the IsEnabled property is dimming an otherwise active control but at this point I'm able to live w/ this downside.

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