protected override void OnAppearing()
 {
     vmAluno        = new XF.Local.AlunoViewModel.AlunoViewModel();
     BindingContext = vmAluno;
     base.OnAppearing();
 }
 public MainPage()
 {
     vmAluno        = new XF.Local.AlunoViewModel.AlunoViewModel();
     BindingContext = vmAluno;
     InitializeComponent();
 }