private void AddUser_Click(object sender, RoutedEventArgs e)
{
if (NameUserTextBox.Text.Trim().Length < 1)
{
MessageBox.Show("Введите значение в текстовое поле!");
return;
}
viewModel.AddItem(NameUserTextBox.Text);
NameUserTextBox.SetBinding(TextBox.TextProperty, new Binding("V")
{
Source = new object()
});
NameUserTextBox.Text = "";
AddButton.Content = "+";
res = true;
}