private void ContentDialog_PrimaryButtonClick(ContentDialog sender, ContentDialogButtonClickEventArgs args)
{
int year = date.Date.Year, month = date.Date.Month, day = date.Date.Day, hour = time.Time.Hours, min = time.Time.Minutes, sec = time.Time.Seconds;
TransactionViewModel.transaction.date = new DateTime(year, month, day, hour, min, sec);
TransactionViewModel.Add();
}