af:panelAccordion partialtrigger on af:selectOneChoice valueChangeListener

Question

I am new in ADF faces and I am facing trouble to partialTrigger a af:panelAccordion on the value change of a af:selectOneChoice. The af:panelAccordion contains multiple af:showDetailHeader within its af:showDetailItem. All the af:showDetailItem and their af:showDetailHeader are generated dynamically. The bean college is in view scope and its code is given below:

public class College {
    private List<Department> departments;
    private List<SelectItem> departmentDropDownMenu;
    private String selectedDepartment;

    public College() {
        this.departments = new ArrayList<Department>(0);

        Employee employee1 = new Employee("Employee 1", "Information");
        Employee employee2 = new Employee("Employee 2", "Information");
        Employee employee3 = new Employee("Employee 3", "Information");
        Employee employee4 = new Employee("Employee 4", "Information");
        Employee employee5 = new Employee("Employee 5", "Information");

        List<Employee> employees1 = new ArrayList<Employee>(0);
        employees1.add(employee1);

        List<Employee> employees2 = new ArrayList<Employee>(0);
        employees2.add(employee2);

        List<Employee> employees3 = new ArrayList<Employee>(0);
        employees3.add(employee3);

        List<Employee> employees4 = new ArrayList<Employee>(0);
        employees4.add(employee4);
        employees4.add(employee5);

        Department department1 = new Department("Department 1", employees1);
        Department department2 = new Department("Department 2", employees2);
        Department department3 = new Department("Department 3", employees3);
        Department department4 = new Department("Department 4", employees4);

        this.departments.add(department1);
        this.departments.add(department2);
        this.departments.add(department3);
        this.departments.add(department4);

        List<SelectItem> departmentDropDownMenu = new ArrayList<SelectItem>(0);
        departmentDropDownMenu.add(new SelectItem("Department 1"));
        departmentDropDownMenu.add(new SelectItem("Department 2"));
        departmentDropDownMenu.add(new SelectItem("Department 3"));
        departmentDropDownMenu.add(new SelectItem("Department 4"));

        this.setDepartmentDropDownMenu(departmentDropDownMenu);
        this.setSelectedDepartment("Department 1");
    }

    public void departmentDropDrownValueChangeListener(ValueChangeEvent event) {
        String oldValue = event.getOldValue().toString();
        String newValue = event.getNewValue().toString();

        if(oldValue.equalsIgnoreCase(newValue)) {
            return;
        }
        List<Department> departmentUpdated = new ArrayList<Department>(0);

        for (Department department : departments) {
            if(department.getDepartmentName().equals(newValue)) {
                departmentUpdated.add(department);
                break;
            }
        }

        for (Department department : departments) {
            if(!department.getDepartmentName().equals(newValue)) {
                departmentUpdated.add(department);                
            }
        }

        this.setDepartments(departmentUpdated);
    }

    public void setDepartments(List<Department> departments) {
        this.departments = departments;
    }

    public List<Department> getDepartments() {
        return departments;
    }

    public void setDepartmentDropDownMenu(List<SelectItem> departmentDropDownMenu) {
        this.departmentDropDownMenu = departmentDropDownMenu;
    }

    public List<SelectItem> getDepartmentDropDownMenu() {
        return departmentDropDownMenu;
    }

    public void setSelectedDepartment(String selectedDepartment) {
        this.selectedDepartment = selectedDepartment;
    }

    public String getSelectedDepartment() {
        return selectedDepartment;
    }
}

The Department and Employee classes are simple POJO. The Department class contains only two fields: 1. String departmentName and 2. List employees with their accessors also the Employee class contains two fields: 1. String name and 2. String info.

The jspx code of the page is given below:

<?xml version='1.0' encoding='UTF-8'?>
<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page" version="2.1" xmlns:f="http://java.sun.com/jsf/core"
          xmlns:af="http://xmlns.oracle.com/adf/faces/rich">
    <jsp:directive.page contentType="text/html;charset=UTF-8"/>
    <f:view>
        <af:document title="Page.jspx" id="d1">
            <af:form id="f1">
                <af:panelStretchLayout id="psl1">
                    <f:facet name="center">
                        <af:panelGroupLayout id="pgl2">
                            <af:selectOneChoice label="Department" value="#{college.selectedDepartment}" id="soc1"
                                                unselectedLabel="" autoSubmit="true" immediate="true"
                                                valueChangeListener="#{college.departmentDropDrownValueChangeListener}">
                                <f:selectItems value="#{college.departmentDropDownMenu}" id="si1"/>
                            </af:selectOneChoice>
                            <af:panelAccordion id="pa1" discloseNone="true" partialTriggers="soc1" discloseMany="true">
                                <af:forEach items="#{college.departments}" var="department">
                                    <af:showDetailItem text="#{department.departmentName}" id="sdi1">
                                        <af:forEach items="#{department.employees}" var="employee">
                                            <af:showDetailHeader text="#{employee.name}" disclosed="false" id="sdh1">
                                                <af:outputText value="#{employee.info}" id="ot1"/>
                                            </af:showDetailHeader>
                                        </af:forEach>
                                    </af:showDetailItem>
                                </af:forEach>
                            </af:panelAccordion>
                        </af:panelGroupLayout>
                    </f:facet>
                </af:panelStretchLayout>
            </af:form>
        </af:document>
    </f:view>
</jsp:root>

What I want to do is to rearrange the af:showDetailItem depending on selected value of the af:selectOneChoice.

I am showing the problem in the images:

As you can see the first image is the normal condition after page load. Department 1 has only one employee viz, Employee 1 and Department 4 has two employees Employee 1, Employee 2. After selecting Department 4 from the dropdown, Department 3 goes into last position but there in Department 3 panel has apparently two af:showDetailItem in the picture but originally it has only one employee. Also that extra af:showDetailItem is not clickable.

If any one please give any suggestion it will be very helpful to me.

Thank you.

Answer 1

The problem is in using <af:forEach/>. According to the tag documentation:

Objects in the items of an <af:forEach> tag should not be added, removed or re-ordered once the component tree has been created

You can use an <af:iterator/> tag instead. JDev will complain that it isn't a valid child of <af:panelAccordion/>, but it does work.

This page layout seems to work. Note, I moved the <af:selectOneChoice/> to the top facet and dumped the <af:panelGroupLayout/> to force the accordion to stretch and make all the children visible.

<?xml version='1.0' encoding='UTF-8'?>
<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page" version="2.1" xmlns:f="http://java.sun.com/jsf/core"
          xmlns:af="http://xmlns.oracle.com/adf/faces/rich">
    <jsp:directive.page contentType="text/html;charset=UTF-8"/>
    <f:view>
        <af:document title="Page.jspx" id="d1">
            <af:form id="f1">
                <af:panelStretchLayout id="psl1">
                    <f:facet name="center">
                            <af:panelAccordion id="pa1" discloseNone="false" partialTriggers="soc1" discloseMany="true" reorder="enable">
                                <af:iterator value="#{college.departments}" var="department">
                                    <af:showDetailItem text="#{department.departmentName}" id="sdi1">
                                        <af:iterator value="#{department.employees}" var="employee">
                                            <af:showDetailHeader text="#{employee.name}" disclosed="false" id="sdh1">
                                                <af:outputText value="#{employee.info}" id="ot1"/>
                                            </af:showDetailHeader>
                                        </af:iterator>
                                    </af:showDetailItem>
                                </af:iterator>
                            </af:panelAccordion>    
                    </f:facet>
                    <f:facet name="top">
                        <af:selectOneChoice label="Department" value="#{college.selectedDepartment}" id="soc1" unselectedLabel="" autoSubmit="true"
                                            valueChangeListener="#{college.departmentDropDrownValueChangeListener}" immediate="true">
                            <f:selectItems value="#{college.departmentDropDownMenu}" id="si1"/>
                        </af:selectOneChoice>
                    </f:facet>
                </af:panelStretchLayout>
            </af:form>
        </af:document>
    </f:view>
</jsp:root>

Hope this helps. Welcome the confusion that is ADF. :)