Question

我有一个带有h:selectManyList和Primefaces commandButton的JSF页面。我想在单击按钮时将新元素添加到列表中。调用按钮的操作方法，但元素不会显示在列表中。我可能只是看不到树林。

页：

<?xml version="1.0"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<html xmlns="http://www.w3.org/1999/xhtml"
    xmlns:h="http://java.sun.com/jsf/html"
    xmlns:p="http://primefaces.org/ui"
    xmlns:f="http://java.sun.com/jsf/core">
<h:head/>
<h:body>
    <h:form id="form">
        <h:messages id="errors"/>
        <h:selectManyListbox id="listBox" value="#{testBean.availableThings}" style="width:100%">
            <f:selectItems value="#{testBean.selectedThings}"/>
        </h:selectManyListbox>
        <br/>
        <p:commandButton id="adder" value="Add" action="#{testBean.addThing}" 
            ajax="true" update="listBox" process="@this listBox"/>
    </h:form>
</h:body>
</html>

支持bean：

import java.util.ArrayList;
import java.util.List;

import javax.faces.model.SelectItem;

@javax.faces.bean.ManagedBean
@javax.faces.bean.ViewScoped
@com.ocpsoft.pretty.faces.annotation.URLMapping(
    id = "testbean",
    pattern = "/testbean/",
    viewId = "/pages/general/testbean.xhtml")
public class TestBean {
    private List<SelectItem> availableThings;
    private List<String> selectedThings;

    public TestBean() {
        availableThings = new ArrayList<>();
        selectedThings = new ArrayList<>();
    }

    public List<SelectItem> getAvailableThings() {
        return availableThings;
    }

    public void setAvailableThings(List<SelectItem> list) {
        this.availableThings = list;
    }

    public List<String> getSelectedThings() {
        return selectedThings;
    }

    public void setSelectedThings(List<String> list) {
        this.selectedThings = list;
    }

    public void addThing() {
        availableThings.add(new SelectItem("item", "item")); // I get this message
        System.err.println("Added item");
    }
}

为什么添加的项目不会出现在列表中，我需要做些什么才能使其显示？

Answer 1

你颠倒了xhtml中的字段。

REST_FRAMEWORK = {
  # Add custom renderer.
  'DEFAULT_RENDERER_CLASSES'=(
              'path.to.CustomJSONRenderer',
              'rest_framework.renderers.JSONRenderer',
              'rest_framework.renderers.BrowsableAPIRenderer'),
  # Add cutom exception handler
  'EXCEPTION_HANDLER': 'path.to.custom_exception_handler'
   }

应该是

<h:selectManyListbox id="listBox" value="#{testBean.availableThings}" style="width:100%">
    <f:selectItems value="#{testBean.selectedThings}"/>
</h:selectManyListbox>

Button不会将项添加到selectManyList

1 个答案: