Question

我将所有AppObjects保留在数组列表中，并能够在第一个下拉框中看到它们，单击添加按钮后，在Java端需要执行的操作以及如何在表单的以下下拉框中显示所选对象非常感谢任何帮助，我是JSF的新手。谢谢

<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:composite="http://java.sun.com/jsf/composite"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:a4j="http://richfaces.org/a4j"
xmlns:rich="http://richfaces.org/rich">

<h:head>
    <title></title>
</h:head>
<h:body>
    <h:form>
        <a4j:outputPanel id="results" ajaxRendered="true">
            <h:panelGrid columns="7">
                <rich:panel header="APP Objects">
                    <rich:select defaultLabel="APP Objects" value="#{searchObjectinDB.chosenAppObject}" listWidth="200">
                        <f:selectItems value="#{searchObjectinDB.AppObjects}" /> 
                        //getting items as list here
                    </rich:select>                                              
                </rich:panel>
                &#160;&#160;&#160;
                <a4j:commandButton id="addAppObject" value="Add" 
                    action="#{searchObjectinDB.getObjectDetails()}" //Upon clicking add button, what needs to be done in this method to show in the below drop down box
                    reRender="selected_objects">
                </a4j:commandButton>
                &#160;&#160;&#160;

                <a4j:outputPanel id="selected_objects">
                    <h:panelGrid columns = "1">
                        <rich:panel header="Selected Objects" style="width: 100%">
                            //need to create another list and display the selected items from first list
                        </rich:panel>
                    </h:panelGrid>
                </a4j:outputPanel>
            </h:panelGrid>
        </a4j:outputPanel>
    </h:form>
<h:body>

我将所有AppObjects保留在数组列表中，并能够在下拉框中看到它们，单击添加按钮后，在Java端需要执行的操作以及如何在下面的下拉框中显示所选对象非常感谢您的帮助，我是JSF的新手

Answer 1

这非常简单，基本上，您只需要一个新集合即可保留所选项目。每次调用方法getObjectDetails时，都会将selectedAppObject变量添加到所选项目的集合中，就像这样：

public class SearchObjectinDB {

   Object chosenAppObject;
   List<Object> AppObjects;
   List<Object> selectedAppObjects = new ArrayList<>();

   //getters and setters

   public void getObjectDetails() {
      selectedAppObjects.add(chosenAppObject);
   }

}

您的XHTML代码还需要创建一个新列表并显示选择的项目：

<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:composite="http://java.sun.com/jsf/composite"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:a4j="http://richfaces.org/a4j"
xmlns:rich="http://richfaces.org/rich">

<h:head>
    <title></title>
</h:head>
<h:body>
    <h:form>
        <a4j:outputPanel id="results" ajaxRendered="true">
            <h:panelGrid columns="7">
                <rich:panel header="APP Objects">
                    <rich:select defaultLabel="APP Objects" value="#{searchObjectinDB.chosenAppObject}" listWidth="200">
                        <f:selectItems value="#{searchObjectinDB.AppObjects}" /> 
                        //getting items as list here
                    </rich:select>                                              
                </rich:panel>
                &#160;&#160;&#160;
                <a4j:commandButton id="addAppObject" value="Add" 
                    action="#{searchObjectinDB.getObjectDetails()}" //Upon clicking add button, what needs to be done in this method to show in the below drop down box
                    reRender="selected_objects">
                </a4j:commandButton>
                &#160;&#160;&#160;

                <a4j:outputPanel id="selected_objects">
                    <h:panelGrid columns = "1">
                        <rich:panel header="Selected Objects" style="width: 100%">
                            <a4j:repeat value="#{searchObjectinDB.selectedAppObjects}" var="item">
                                <tr>
                                    <td><h:outputText value="#{item.toString}" id="item1" /></td>
                                </tr>
                            </a4j:repeat>
                        </rich:panel>
                    </h:panelGrid>
                </a4j:outputPanel>
            </h:panelGrid>
        </a4j:outputPanel>
    </h:form>
<h:body>

想要从jsf下拉框中选择一个值，然后点击添加按钮后需要在底部的下拉框中显示

1 个答案: