public ChatsPageViewModel() { //FriendsList OnFriendsListCommand = new Command(async() => { await App.Current.MainPage.Navigation.PushAsync(new FriendListPage()); }); //Logout OnLogoutCommand = new Command(() => { UserSetting.ClearEverything(); //clear all User data. App.Current.MainPage = new NavigationPage(new AuthenticationPage()); //go back logout screen }); }