Working with af:iterator and af:forEach programmatically (Add and delete records using List)

In previous post Working with af:iterator and af:forEach programmatically (Populate values using POJO from Managed Bean) we saw that how can we populate record from a List to af:iterator and af:forEach (ADF Faces Component)

So this post is about adding and deleting of records from List while List is presented using af:iterator.
here i am extending previous post and using same sample application



Added two fields and button on page to add records 

<af:panelFormLayout id="pfl1" rows="1">
                    <af:inputText label="Name" id="it1" binding="#{viewScope.PopulateIteratorBean.nameBind}"/>
                    <af:inputText label="Department" id="it2" binding="#{viewScope.PopulateIteratorBean.deptNameBind}"/>
                    <af:button text="Add" id="b1"
                               actionListener="#{viewScope.PopulateIteratorBean.addNewRecordAction}"/>
                </af:panelFormLayout>

and on this button action simply added both attributes to List and added partial trigger of button to af:iterator to refresh it

    // Component binding to access inputValue from page
    
    private RichInputText nameBind;
    private RichInputText deptNameBind;
    
    public void setNameBind(RichInputText nameBind) {
        this.nameBind = nameBind;
    }

    public RichInputText getNameBind() {
        return nameBind;
    }

    public void setDeptNameBind(RichInputText deptNameBind) {
        this.deptNameBind = deptNameBind;
    }

    public RichInputText getDeptNameBind() {
        return deptNameBind;
    }

    /**Method to add record in List and show on page using af:iterator and af:forEach
     * @param actionEvent
     */
    public void addNewRecordAction(ActionEvent actionEvent) {
        if (nameBind.getValue() != null && deptNameBind.getValue() != null) {
            EmployeeDet obj = new EmployeeDet(nameBind.getValue().toString(), deptNameBind.getValue().toString());
            employeeDetail.add(obj);
            
        }
    }

On page - add a new record (record added in List and appeared in iterator as well)

So it is quite simple to add records but deletion of record is a bit tricky but not difficult at all :)
Let's see this-
For deleting record i have added a delete link inside iterator so that it should appear for each record as you can see in snap (above)
Here question is that how to know that which record should be deleted  ?

So for this i have added a f:attribute tag to link , this attribute contains the value of current item of iterator

f:attribute derives it's value from var of af:iterator/af:forEach, this var represents each item of List
Now on delete button's action - get the current item and remove it from List

    /**Method to delete selected record
     * @param actionEvent
     */
    public void deleteRecordAction(ActionEvent actionEvent) {
        //Get value from f:attribute (current item)
       Object itemVal= actionEvent.getComponent().getAttributes().get("itemVal");
       //Remove selected item from List
       employeeDetail.remove(itemVal);
    }

After deleting records

Sample ADF Application- Download

Working with af:iterator and af:forEach programmatically (Populate values using POJO from Managed Bean)

This is another post about Working programmatically with ADF (populating af:iterator and af:forEach programmatically )

Previously i have posted about populating af:iterator and af:forEach using ADF BC and binding layer to show master-detail relation
Implementing master/detail tree relation using af:Iterator and af:forEach for better UI designs - Oracle ADF

For this post i am populating employee name and it's department name using List datastructure ,to get and set value of attributes

Created a java bean class , it has 2 variable for both attributes

public class EmployeeDet {
    public EmployeeDet(String name, String deptName) {
        this.name = name;
        this.deptName = deptName;
    }
    //Attribute to display EmployeeName and Department Name
    private String name;
    private String deptName;

    public void setName(String name) {
        this.name = name;
    }

    public String getName() {
        return name;
    }

    public void setDeptName(String deptName) {
        this.deptName = deptName;
    }

    public String getDeptName() {
        return deptName;
    }
}

Next step is to create a managed bean to populate data in af:iterator and af:forEach , this managed bean makes use of

EmployeeDet 

java bean class to add data in same format for all items of iterator and forEach. A List data structure is used to pass all values to iterator. See code of managed bean 

    //Constructor-populate default records
    public PopulateIteratorBean() {

        EmployeeDet obj = new EmployeeDet("Ashish Awasthi", "Oracle ADF");
        employeeDetail.add(obj);
        obj = new EmployeeDet("Alex Smith", "Java");
        employeeDetail.add(obj);
        obj = new EmployeeDet("James S", "PHP");
        employeeDetail.add(obj);
    }
    //ArrayList to poplate data in af:iterator and af:forEach
    private List<EmployeeDet> employeeDetail = new ArrayList();

    public void setEmployeeDetail(List<EmployeeDet> employeeDetail) {
        this.employeeDetail = employeeDetail;
    }

    public List<EmployeeDet> getEmployeeDetail() {

        return employeeDetail;
    }

Now drop af:iterator on page and set it's properties like value, var etc

using var reference of iterator , set value in output text to show Employee Name and DepartmentName , see XML source of af:iterator

<af:panelGroupLayout id="pgl1" layout="horizontal">
                        <af:iterator id="i1" value="#{viewScope.PopulateIteratorBean.employeeDetail}" var="item">
                            <af:panelBox id="pb2" showDisclosure="false">
                                <f:facet name="toolbar"/>
                                <af:panelGroupLayout id="pgl3" layout="horizontal">
                                    <af:outputText value="#{item.name}" id="ot1"
                                                   inlineStyle="font-weight:bold; font-size:medium; color:#0572ce;;"/>
                                    <af:spacer width="2" height="0" id="s1"/>
                                    <af:outputText value="(#{item.deptName})" id="ot2"
                                                   inlineStyle="font-weight:bold;font-size:small;color:red;"/>
                                </af:panelGroupLayout>
                            </af:panelBox>
                        </af:iterator>
                    </af:panelGroupLayout>  

on running it looks like this-

do same for af:forEach

<af:panelGroupLayout id="pgl2" layout="horizontal">
                        <af:forEach items="#{viewScope.PopulateIteratorBean.employeeDetail}" var="feach">
                            <af:showDetailHeader text="#{feach.deptName}" disclosed="true" id="sdh1">
                                <af:outputText value="#{feach.name}" id="ot3"
                                               inlineStyle="font-weight:bold; font-size:medium; color:#0572ce;;"/>
                            </af:showDetailHeader>
                        </af:forEach>
                    </af:panelGroupLayout>

on running it looks like this-

 Sample ADF Application-Download
Thanks, Happy Learning :)

Custom selection listener for af:listView, Invoke selectionListener programmatically

In the last post (Better UI for data collection using af:listView, Enable selection in ADF Faces List component ) about af:listView, we saw that how can we present data collection in a better way using af:listView and enable selection using EL (same as used for af:table)

Now in this post i will describe about defining custom selection listener for af:listView
Suppose you have to do some task on selection of an item in list other than making it current row, for this you have to override default selection listener and define own custom selection listener in managed bean
So next step is to define a method in managed bean for handling selection event of af:list view

• Select af:listView, goto properties and click on edit menu of selectionListener property and create a method in managed bean








• now see what we have to do in custom selection listener, first invoke default selection listener EL (#{bindings.Departments1.collectionModel.makeCurrent}) to make selected row as current and then get current row from iterator as selected row is now current row
  See the managed bean code -



//Import these packages

import javax.el.ELContext;
import javax.el.ExpressionFactory;
import javax.el.MethodExpression;
import javax.el.ValueExpression;

import javax.faces.application.FacesMessage;
import javax.faces.context.FacesContext;

import oracle.jbo.Row;

import org.apache.myfaces.trinidad.event.SelectionEvent;   


 /**
     * Programmatic invocation of a method that an EL evaluates to.
     *
     * @param el EL of the method to invoke
     * @param paramTypes Array of Class defining the types of the parameters
     * @param params Array of Object defining the values of the parametrs
     * @return Object that the method returns
     */
    public static Object invokeEL(String el, Class[] paramTypes, Object[] params) {
        FacesContext facesContext = FacesContext.getCurrentInstance();
        ELContext elContext = facesContext.getELContext();
        ExpressionFactory expressionFactory = facesContext.getApplication().getExpressionFactory();
        MethodExpression exp = expressionFactory.createMethodExpression(elContext, el, Object.class, paramTypes);

        return exp.invoke(elContext, params);
    }

    /**
     * Programmatic evaluation of EL.
     *
     * @param el EL to evaluate
     * @return Result of the evaluation
     */
    public static Object evaluateEL(String el) {
        FacesContext facesContext = FacesContext.getCurrentInstance();
        ELContext elContext = facesContext.getELContext();
        ExpressionFactory expressionFactory = facesContext.getApplication().getExpressionFactory();
        ValueExpression exp = expressionFactory.createValueExpression(elContext, el, Object.class);

        return exp.getValue(elContext);
    }

    /**Custome Selection Listener for af:listView
     * @param selectionEvent
     */
    public void listSelectionListener(SelectionEvent selectionEvent) {
        //invoke this EL to set selected row as current row, if it is not invoked then first row will be current row
        invokeEL("#{bindings.Departments1.collectionModel.makeCurrent}", new Class[] { SelectionEvent.class }, new Object[] {
                 selectionEvent });
        // get the selected row , by this you can get any attribute of that row
        Row selectedRow = (Row) evaluateEL("#{bindings.Departments1Iterator.currentRow}");
        FacesMessage msg = new FacesMessage(selectedRow.getAttribute("DepartmentName").toString());
        msg.setSeverity(FacesMessage.SEVERITY_INFO);
        FacesContext.getCurrentInstance().addMessage(null, msg);
    }



• Now run application and check

Download Sample ADF Application here
Thanks , Happy Learning :)