protected override void OnAppearing()
 {
     base.OnAppearing();
     BindingContext = Bill;
     if (Bill != null && Bill.Id != 0)
     {
         CreditCardDAL creditCardDAL = new CreditCardDAL();
         btn.Text = creditCardDAL.Find(Bill.CreditCarkId).CardNumber;
     }
 }
 public async Task btn_Click(object sender, EventArgs e)
 {
     if (btn.Text != null)
     {
         CreditCardDAL creditCardDAL = new CreditCardDAL();
         var           credit        = creditCardDAL.Find(btn.Text);
         if (credit != null)
         {
             CreditCardDetail creditCardDetail = new CreditCardDetail();
             creditCardDetail.CreditCard = credit;
             await Navigation.PushAsync(creditCardDetail);
         }
     }
 }