private void editExpenseBtn_Click(object sender, RoutedEventArgs e)
 {
     ExpenseInfo expenseToEdit = GetSelectedItem();
     if (expenseToEdit != null)
      {
          Funds.AddExpenseWindow AddExpenseWindowObj = new Funds.AddExpenseWindow(expenseToEdit);
          AddExpenseWindowObj.Show();
      }
 }
 private void addExpenseBtn_Click(object sender, RoutedEventArgs e)
 {
     Funds.AddExpenseWindow AddExpenseWindowObj = new Funds.AddExpenseWindow(null);
     AddExpenseWindowObj.Show();
 }