ADF Basics: Using setActionListener in ADF, Set pageFlowScope parameter without writing code

This post is about using setActionListener tag in ADF, this tag provides a simpler way to set values of other objects and makes use of EL
See What docs says-

The setActionListener tag is a declarative way to allow an action source (<commandButton>, <commandLink>, etc.) to set a value before navigation. It is perhaps most useful in conjunction with the "pageFlowScope" EL scope provided by ADF Faces, as it makes it possible to pass details from one page to another without writing any Java code. This tag can be used both with ADF Faces commands and JSF standard tags. More generally, it can be used with any component at all that implements the standard ActionSource interface.

Set and Get Value from Taskflow parameter (pageFlowScope variable) from Managed Bean- ADF

Hello All

This post is about getting and setting value in taskFlow parameter using Java Code so for that we have created a application with bounded taskFlow

Let's see how to do this -

We have bounded taskflow having Input Parameter defined in it named GLBL_PARAM_TEST

and we have to set its value from managed bean.
this is very simple -see how to do that

• Get pageFlowScope Map and put parameter 's value in it



        Map paramMap = RequestContext.getCurrentInstance().getPageFlowScope();
        paramMap.put("GLBL_PARAM_TEST", "Ashish"); 



• And get Value from taskFlow parameter in managed bean





    public String resolvEl(String data){
               FacesContext fc = FacesContext.getCurrentInstance();
               Application app = fc.getApplication();
               ExpressionFactory elFactory = app.getExpressionFactory();
               ELContext elContext = fc.getELContext();
               ValueExpression valueExp = elFactory.createValueExpression(elContext, data, Object.class);
               String Message=valueExp.getValue(elContext).toString();
               return Message;
             }


String param=resolvEl("#{pageFlowScope.GLBL_PARAM_TEST}");

Beauty of ADF- Taskflow, Difference b/w Facelets and JSP XML fragments in bounded taskflow

Oracle ADF framework support modular architecture for enterprize application development. Multiple small module can be bound together to form a large module .
The greatest advantage of ADF controller over core JSF navigation model is that it splits a single bulky module to multiple reusable and interconnected modules known as Taskflows.

i am not going deeper in Taskflows as every ADF developer know about it ,so the important part is page fragment.

• When  we create taskflow as bounded taskflow , and check it to create fragment in taskflow.

• Now when we create pagefragment in bounded taskflow, there is 2 option for creating fragment

Create fragment as Facelets
Create fragment as JSP XML 

Facelets- is default and official view handler for JSF pages, priviously JSP was used to view JSF pages but it didn't support all component so Facelets comes in picture under APACHE open source license. It supprts all UI component used by JSF (Java Server Faces).
Facelets was developed by Jacob Hookom in 2005.
If you create Facelets fragment in bounded taskflow, then taskflow must be dropped in a JSF page (parent page) not in .jspx (JSP XML ) page.
if you try to drop it into JSP XML page-

JSP XML- jspx is XML variant of JSP(Java Server Pages) to support XML document . JSP XML fragments are used in ADF inorder to support XML document and more powerful page validation techniques.
If you create jsp xml fragments in bounded taskflow, then taskflow must be dropped in a JSP XML(.jspx) page(parent page) not in JSF page.

Using Contextual Event in Oracle ADF (Region Communication)

Contextual event ,in simple terms is a way to communicate between taskflows.

Sometimes we have taskflow open in a region and have to get some values from that taskflow .

This scenario can be achieved by contextual event.

 

Contextual Event have two parts-

1. Publisher Event (Producer)- As button or any component that can raise event 
2. Handler Event (Customer)- that listens and process event published by producer

This tutorial is based on example developed on default HR schema of Oracle DB 11g

I have created two application and called first one in secod application as region.

• Create first application using Department table of HR schema and drag Department Name on page fragment, now create publisher event (follow steps) for Department Name .
• Select Department Name field in structure window and go to property Inspector select ContextualEvent
  click on green add icon and select event type and name for publisher event

 

• Select field value from Iterator Binding
  
• here you are done with publisher event or producer create a jar of this application in order to use it in second application.
• Now start Second Application that will handle and process this event, create a page and put an output text and set its value from managed bean
  
  
  
  
  
  

• Now create a event handler class to process published event and to make it available to page binding level , we have to create DataControl for this class.
  
  
  
  
  
  
  
  
• Right click on event class and Click on CreateDataControl.
• Now add this method binding to page so that it can be accessible from page binding

• Now drag and drop taskflow from jar library on page as region by this published event will also be available to page
  

  
• Now go to page binding and goto ContextualEvents tab ,click on subscribers tab and click on add icon this will open a popup window ,click on search button , it will show available publisher event, now select event and goto handler search option and select function that you have previously added in page binding
• Give consumer parameter name same as event handler function

 

Now Run your Application - Download ADF Sample Application

Most Used Codes in ADF (Iterate over ViewObject, get Value from pageFlow Scope variable)

Iterate Over View Object-

Some times we need to iterate in table to check for some validation as we have  to check for duplicate record, we want to delete all data of table with one click.

then we have to get all rows of table- this is a very common use case in ADF, so you can use following snippet of code to do this

1. Using AllRowInRange method to get rows available in range

  ViewObject vo=am.getViewObject();


   // Get All Rows in range of ViewObject in an Array
    Row[] rArray=vo.getAllRowsInRange();
    
    //Loop over array of Rows
    for(Row r:rArray){

       /*your operation code*/

       }

2. Using RowSetIterator-

  ViewObject vo = this.getViewObject();
       
       //Create RowSetIterator
        RowSetIterator rsi = vo.createRowSetIterator(null);
       //Iterate Over this to get all rows
        while (rsi.hasNext()) {
            Row nextRow = rsi.next();
            
        }
        rsi.closeRowSetIterator();

Get Value from taskFlow parameter(Using pageFlow Scope)-

we can get value from TaskFlow parameter using pageflow scope and can use it in Our Bean.

Suppose we have defined a parameter in page to pass Session_Id.

We can get it using pageflow scope

Integer sessionId = Integer.parseInt(resolvEl("#{pageFlowScope.Session_Id}"));

 Code For resolvEl-

    public String resolvEl(String data) {
        FacesContext fc = FacesContext.getCurrentInstance();
        Application app = fc.getApplication();
        ExpressionFactory elFactory = app.getExpressionFactory();
        ELContext elContext = fc.getELContext();
        ValueExpression valueExp = elFactory.createValueExpression(elContext, data, Object.class);
        String Message = valueExp.getValue(elContext).toString();
        return Message;
    }