Question

我试图在Vaadin中编写验证，但我不明白如何检查日期字段是否为空

我写了这样的东西

    @Override
    public void setConfiguration(EditorConfiguration editorConfiguration) {
    boolean required = ((DateFieldConfiguration) editorConfiguration).isRequired();
    if (required == true) {
        setRequiredIndicatorVisible(true);
        addValueChangeListener(event -> validate(event.getSource().getDefaultValidator(), event.getValue()));

    }

}

    private void validate(Validator<LocalDate> defaultValidator, LocalDate localDate) {

      binder.forField(this).withValidator(validator).asRequired("Mandatory").bind(s -> getValue(),
            (b, v) -> setValue(v));

}

我已经通过文本字段进行了验证：

字符串验证器代码

public class VaadinStringEditor extends TextField implements HasValueComponent<String> {

/**
 * 
 */
private static final long serialVersionUID = 6271513226609012483L;
private Binder<String> binder;

@PostConstruct
public void init() {
    setWidth("100%");
    binder = new Binder<>();
}

@Override
public void initDefaults() {
    setValue("");
    binder.validate();
}

@Override
public void setConfiguration(EditorConfiguration editorConfiguration) {
    Validator<String> validator = ((TextFieldConfiguration) editorConfiguration).getValidator();
    if (validator != null) {
        binder.forField(this).withValidator(validator).asRequired("Mandatory").bind(s -> getValue(),
                (b, v) -> setValue(v));

    }

我在这里有效：

question.setEditorConfiguration(new TextFieldConfiguration(textRequiredValidator()));

验证

    private Validator<String> textRequiredValidator() {
    return Validator.from(v -> v != null && StringUtils.trimAllWhitespace((String) v).length() != 0,
            , "Not empty");
}

Answer 1

您应该com.vaadin.ui.DateField使用LocalDate值。看看下面的例子。

示例bean：

public class MyBean {
    private LocalDate created;

    public LocalDate getCreated() {
        return created;
    }

    public void setCreated(LocalDate created) {
        this.created = created;
    }
}

编辑

DateField dateField = new DateField("Date selector");
binder.forField(dateField)
        .bind(MyBean::getCreated, MyBean::setCreated);

如果由于某种原因你希望com.vaadin.ui.TextField有编辑日期，那么你需要像这样设置转换器：

Binder<MyBean> binder = new Binder<>();
TextField textDateField = new TextField("Date here:");
binder.forField(textDateField)
        .withNullRepresentation("")
        .withConverter(new StringToLocalDateConverter())
        .bind(MyBean::getCreated, MyBean::setCreated);

转换器实施：

public class StringToLocalDateConverter implements Converter<String, LocalDate> {
    @Override
    public Result<LocalDate> convertToModel(String userInput, ValueContext valueContext) {
        try {
            return Result.ok(LocalDate.parse(userInput));
        } catch (RuntimeException e) {
            return Result.error("Invalid value");
        }
    }

    @Override
    public String convertToPresentation(LocalDate value, ValueContext valueContext) {
        return Objects.toString(value, "");
    }
}

请注意，此转换器不使用ValueContext对象，该对象包含在更复杂的情况下应考虑的信息。例如，应该处理用户区域设置。

Vaadin验证日期，不是空的

1 个答案: