java - 如何在 Vaadin 上使用 withConverter 方法防止 Binder 中出现 “null” 文本

Question

使用Binder时如何防止显示文本“null” withConverter方法

    TextField id = new TextField("Id");
    TextField name = new TextField("Name");

        Binder<Customer> b = new Binder<>();

        b.forField(id)
                .withConverter(Integer::valueOf, String::valueOf, "Invalid")
                .bind(Customer::getId, Customer::setId);
        b.forField(name)
                .bind(Customer::getName, Customer::setName);
        b.readBean(customer);

结果是这样的:

How do the conversion without losing the validation type?

Answer 1

最后，我找到了使用vaadin API的解决方案，感谢帮助@Shirkam

    b.forField(id)
            .withConverter(Integer::valueOf, String::valueOf, "Invalid")
            .withNullRepresentation(0)
            .withValidator(new IntegerRangeValidator("Value must be greater than 0 ", 1, null))
            .bind(Customer::getId, Customer::setId);
    b.forField(name)
            .bind(Customer::getName, Customer::setName);
    b.readBean(customer);