NavigationPageU.cs

public class NavigationPageU : NavigationPage
    {

        public NavigationPageU(){}

        //Implements initial page in constructor
        public NavigationPageU(Page p) => Task.Run(() => { PushAsync(p); });


        public new Task PushAsync(Page page,bool animated = false)
        {
            if (Navigation.NavigationStack.Count > 0 &&  (page.GetType() == Navigation.NavigationStack.Last().GetType()))
            {
                return Task.FromResult(false);
            }
            return base.PushAsync(page, animated);
        }

        public Task PushModalAsync(Page page, bool animated)
        {
            if (Navigation.NavigationStack.Count > 0 && (page.GetType() == Navigation.NavigationStack.Last().GetType()))
            {
                return Task.FromResult(false);
            }
            return Navigation.PushModalAsync(page, animated);
        }




    }