Refreshing ADF region

• We can configure region, refreshes to invoke the task flow 
• ADF region can invoke the task flow if the region is in active state 

There are two type of refresh options
1) Default - Refreshes the region when the page loads and RefreshCondition=true.
2) ifNeeded - Refreshes the region if the value of the flow binding parameters changes.ifNeeded Option is set do not set the refresh condition

Shown above are the activation options for a region

Conditional -Refreshes the region if true
Differed - This is relevant if the the applications uses Faceletes XHTML pages
Immediate - Refresh the region immediately.Region refresh when the page displays

There are 3 ways of refreshing the region

1) Neither refresh or RefreshCondition specified ,Region refreshes the parent page displays
2) ADF region get refreshes when the RefreshConditions EL returns true .Refresh condition is independent of the changing value of binding parameters
3) ifNeeded is set for the Refresh option.Any change of value of binding parameters the refresh take place.ifNeeded selected no RefreshCondition specified.

Lets go through an example demonstrating the refresh condition
Create a task flow

Create a managed bean in pageflowscope of the task flow.

package view;

import java.util.HashMap;

import java.util.Map;

import oracle.adf.view.rich.context.AdfFacesContext;

public class RegionMap {

    private boolean refresh;

    private String time;

    public void setTime(String time) {

        this.time = time;

    }

    public void setRefresh(boolean refresh) {

        this.refresh = refresh;

    }

    public boolean isRefresh() {

        String flag =(String) AdfFacesContext.getCurrentInstance().getPageFlowScope().get("varFlag");

     

        if ("true".equals(flag))

            return true;

        else

            return false;

    }

    public RegionMap() {

        super();

    }

    public Map getMyMap() {

        Map map = new HashMap();

        map.put("test1", "test1");

        map.put("test2", "test2");

        return map;

    }

    public String getTime() {

        long t =System.currentTimeMillis();

        System.out.println(t);

        return "" + t;

    }

    public boolean refreshRegion() {

        AdfFacesContext.getCurrentInstance().getPageFlowScope().put("curTime", System.currentTimeMillis());

        return true;

    }

    public String testMeth() {

        String flag=("true".equals((String) AdfFacesContext.getCurrentInstance().getPageFlowScope().get("varFlag")) ? "false" :

         "true");

        AdfFacesContext.getCurrentInstance().getPageFlowScope().put("varFlag", flag);

        System.out.println("Flag =" + flag);

        // Add event code here...

        return null;

    }

}

 Drag and drop the task flow to testRefreshRegion.jspx as a region and set the refresh condition as shown below

The code for testRefreshRegion.jspx is as 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="testRefreshRegion.jspx" id="d1">

            <af:form id="f1">

                <af:region value="#{bindings.regionRefresh1.regionModel}" id="r1"/>

                <af:button text="button 1" id="b1" action="#{pageFlowScope.RegionMap.testMeth}"/>

            </af:form>

        </af:document>

    </f:view>

</jsp:root>

We need to add the managed bean to adfc-config.xml to visible to this page.Run the page. Click on the button based on the pageFlowScope variable = true the region will get refreshed.

ifNeeded and Binding variable change 

 Change the refresh property to ifNeeded as below .

Code for the testRefreshRegion.jspx is as 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="testRefreshRegion.jspx" id="d1">

            <af:form id="f1">

                <af:region value="#{bindings.regionRefresh1.regionModel}" id="r1"/>

                <af:button text="button 1" id="b1" action="#{pageFlowScope.RegionMap.testMeth}"/>

                <af:button text="button 2" id="b2" action="#{pageFlowScope.RegionMap.testChange}"/>

            </af:form>

        </af:document>

    </f:view>

Added button 2 here with action method as #{pageFlowScope.RegionMap.testChange}

Add testChange() method to the managed bean.

    public String testChange() {

        AdfFacesContext.getCurrentInstance().getPageFlowScope().put("changeVar", getTime());

       

        // Add event code here...

        return null;

    }

Go to the page Def file of the testRefreshRegionPage.jspx and add parameters there .

<?xml version="1.0" encoding="UTF-8" ?>

<pageDefinition xmlns="http://xmlns.oracle.com/adfm/uimodel" version="12.1.2.66.68" id="testRefreshRegionPageDef"

                Package="view.pageDefs">

  <parameters/>

  <executables>

    <variableIterator id="variables"/>

    <taskFlow id="regionRefresh1" taskFlowId="/WEB-INF/regionRefresh.xml#regionRefresh" activation="deferred"

              xmlns="http://xmlns.oracle.com/adf/controller/binding" Refresh="ifNeeded">

      <parameters>

        <parameter id="parameter" value="#{pageFlowScope.changeVar}"/>

      </parameters>

    </taskFlow>

  </executables>

  <bindings/>

</pageDefinition>

Run the page and click on the 2nd button to see the region refreshes .