仅当验证失败时，输入字段才会保留以前的值 [英] Input fields hold previous values only if validation failed

问题描述

我想出了一个奇怪的问题.我试图隔离问题，所以以下是我的简化代码.

I came up with a strange problem. I tried to isolate the problem so following is my simplified code.

public class MyBean {

  private List<Data> dataList;
  Data selectedData;

  public MyBean() {
    dataList = new ArrayList<Data>();
    dataList.add(new Data("John", 16));
    dataList.add(new Data("William", 25));
  }

  public List<Data> getDataList() {
    return dataList;
  }

  public void edit(Data data) {
    selectedData = data;
  }
  public void newData() {
    selectedData = new Data(null, null);
  }

  public Data getSelectedData() {
    return selectedData;
  }

  public class Data {
    String name;
    Integer age;
    Data(String name, Integer age) {
      this.name = name;
      this.age = age;
    }
    public String getName() {
      return name;
    }
    public void setName(String name) {
      this.name = name;
    }
    public Integer getAge() {
      return age;
    }
    public void setAge(Integer age) {
      this.age = age;
    }
  }
}

xhtml:

<rich:modalPanel id="pop">
  <h:form>
    Name: <h:inputText value="#{myBean.selectedData.name}" required="true" id="txtName"/><br/>
    Age : <h:inputText value="#{myBean.selectedData.age}" required="true" id="txtAge"/>
    <a4j:commandButton value="Save"/>
    <a4j:commandButton value="Close" onclick="Richfaces.hideModalPanel('pop');return false;"/>
    <br/>
    <rich:message for="txtName"/><br/>
    <rich:message for="txtAge"/>
  </h:form>     
</rich:modalPanel>

<h:form>
  <rich:dataTable value="#{myBean.dataList}" var="data">
    <rich:column>#{data.name}</rich:column>
    <rich:column>
      <a4j:commandLink value="Edit" action="#{myBean.edit(data)}" reRender="pop" oncomplete="Richfaces.showModalPanel('pop')"/>
    </rich:column>
  </rich:dataTable>
  <a4j:commandButton value="New" action="#{myBean.newData()}" reRender="pop" oncomplete="Richfaces.showModalPanel('pop')"/>
</h:form>

这是错误的路径:

1. 加载页面
2. 点击第一行的编辑"链接(弹出窗口)
3. 在弹出窗口中，清除年龄"字段并点击保存".(显示必填信息)
4. 点击取消(不填写年龄"字段)
5. 点击第二个链接.
6. 现在它显示不相关的数据(以前的数据).- 这就是问题
7. 即使我点击新建"按钮，它也会显示不正确的数据.
   

仅当弹出窗口中的验证失败时才会发生这种情况.
有解决办法吗?

This happens only if a validation is failed in the popup.
Is there a solution for this?

推荐答案

这个问题在 JSF 2 中也得到了认可，并在下面的回答中详细解释了:发生验证错误后如何使用 PrimeFaces AJAX 填充文本字段? 如果您使用的是 JSF 2，则可以使用 OmniFaces 的 ResetInputAjaxActionListener 或 PrimeFaces 的 <p:resetInput>或 resetValues="true" 为此.

This problem is in JSF 2 also recognized and explained in detail in the following answer: How can I populate a text field using PrimeFaces AJAX after validation errors occur? If you were using JSF 2, you could have used OmniFaces' ResetInputAjaxActionListener or PrimeFaces' <p:resetInput> or resetValues="true" for this.

说到点子上，你需要清除 EditableValueHolder 组件即将进行 ajax 渲染，但未包含在 ajax 执行中.要清除状态，在 JSF 2 中您将使用便捷方法 resetValue() 为此，但这在 JSF 1.2 中不可用，您需要调用 4 个单独的方法 setValue(null), setSubmittedValue(null), setLocalValueSet(false), setValid(true) 清除状态.

To the point, you need to clear the state of the EditableValueHolder component when it's about to be ajax-rendered, but which isn't included in the ajax-execute. To clear the state, in JSF 2 you would have used the convenience method resetValue() for this, but this isn't available in JSF 1.2 and you need to invoke the 4 individual methods setValue(null), setSubmittedValue(null), setLocalValueSet(false), setValid(true) to clear the state.

要确定哪些组件将被 ajax 渲染，但不被 ajax 执行，在 JSF 2 中，您将为此使用 PartialViewContext 方法，但这在 JSF 中不可用1.2 还没有标准化 ajax.您需要摆弄 RichFaces 特定的 ajax API 才能弄清楚这一点.我无法从头顶上看出这一点，所以这是一个启动示例，假设您已经知道需要清除的组件.想象一下弹出窗口中的表单有 id="popForm" 并且名称输入字段有 id="nameInput"，下面是如何在 中清除它newData() 方法:

To figure out which components are to be ajax-rendered, but aren't been ajax-executed, in JSF 2 you would have used PartialViewContext methods for this, but this is not available in JSF 1.2 which hasn't standardized ajax yet. You'd need to fiddle with RichFaces specific ajax API in order to figure that. I can't tell that from top of head, so here's a kickoff example assuming that you already know the components which needs to be cleared. Imagine that the form in your popup has id="popForm" and the name input field has id="nameInput", here's how you could clear it inside the newData() method:

UIInput nameInput = (UIInput) context.getViewRoot().findComponent("popForm:nameInput");
nameInput.setValue(null);
nameInput.setSubmittedValue(null);
nameInput.setLocalValueSet(false);
nameInput.setValid(true);

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