public void PrinterNavigateToAddEditContact(ContactView contact, object o)
 {
     //phtkiet
     //if (this.AppFrame.CanGoBack)
     try
     {
         if (this.AppFrame.BackStack.Count > 1)
             this.AppFrame.BackStack.RemoveAt(this.AppFrame.BackStack.Count - 2);
         GC.Collect();
     }
     catch (Exception ex)
     {
         System.Diagnostics.Debug.WriteLine(ex.ToString());
     }
     //phtkiet
     var x = new Page_AddEditContact(contact, 2, o);     // 2: mode printer        
     AppFrame.Navigate(x.GetType());
 }
 public void NavigateToAddEditContact(ContactView contact)
 {
     //phtkiet
     //if (this.AppFrame.CanGoBack)
     try
     {
         if (this.AppFrame.BackStack.Count > 1)
             this.AppFrame.BackStack.RemoveAt(this.AppFrame.BackStack.Count - 2);
         GC.Collect();
     }
     catch (Exception ex)
     {
         System.Diagnostics.Debug.WriteLine(ex.ToString());
     }
     //phtkiet
     var editPage = new Page_AddEditContact(contact, 1, null);
     AppFrame.Navigate(editPage.GetType());
 }