tapping into shake motion with xamarin forms

I'd like to setup hockeyapp to trigger the feedback upon shake gesture in Ios as listed here
https://support.hockeyapp.net/kb/general-account-management-2/invoking-feedback-ui-with-a-shake-gesture

Add the following code to your BaseView.cs file:

public override void MotionEnded(UIEventSubType motion, UIEvent event)
{
if (motion == UIEventSubType.MotionShake)
{
BITHockeyManager.SharedHockeyManager.FeedbackManager.ShowFeedbackComposeViewWithGeneratedFeedback();
}
}

But how do I tap into the base view class in xamarin forms?