Cascading List of Values in ADF

Hi Friends,

This article explains about the concepts of Cascading lov in ADF . Cascading LOV is the most common requirement in ADF we come across, But i haven't found single blog which had listed out the detailed steps to create Cascaded LOV , in this post i will going to cover each and every step of Cascaded LOV creation process.

Before we begin the process LOV creation process, I would like to create some database tables , relationship between this tables and Insert some data into tables. Below link contain scripts to create database tables and insert data into tables.

https://drive.google.com/file/d/0B7aSuIl4TDKJRk5VNmdvdW1xamc/view?usp=sharing

Once we are done with the process , then we can proceed further with Cascaded LOV creation Process.

Before we begin i would like to show how page looks with cascading LOV .

Here "BusinessUnit" is Parent LOV , upon the selection of Parent LOV values , child LOV that is "Practice" values display relevant values with respect to Parent lov

So two View objecs one for Business unit and other for Practice will be created and Businessunit id will be passed as reference in Practice View Object to filter out values based on the Parent value selection

Now we will follow below steps to achieve it.

1. Create Applications à Fusion Web Application (ADF)

2. Click on Ok and Create Application with below names

Application Name	CascadedLOVApp
Application Package Prefix	Demo.adf.CascadedLOVApp

3. Subsequently click on Next to Finish it

After Completion of Application Creation Process , The next process to create BC4J Components , like View Objects and Application Module

4. Create View Object by clicking on Model and then ADF Business Components

Provide Database Details to Connect to Database

Click on Ok to Provide VO object Name and its Package.

Package Name	Demo.adf.CascadedLOVApp.model.server
View Object Name	DualVO

Then further Next to Proceed to Provide Query

Below Query needs to be Pasted.

SELECT '' EMPLOYE_ID, ''EMPLOYEE_NAME , '' BUSINESS_UNIT,'' PRACTICE FROM DUAL

Click on Each attribute VO to make it as "Updateable" to "Always"

Click on Next

And then click on Finish to Complete the Process

Similarly we will going to create other View Objects by following the above Process.

Creating BusinessUnitVO with below Nomenclature

Package Name	Demo.adf.CascadedLOVApp.model.server
View Object Name	BusinessUnitVO

Write following query to Provide View Object Query

SELECT BUSINESS_UNIT_ID,BUSINESS_UNIT_NAME FROM XX_BUSINESS_UNITS

and then click on Subsequent Next Button to finish the BusinessUnitVO creation Process

Create Another ViewObject with a name PracticeVO

Package Name	Demo.adf.CascadedLOVApp.model.server
View Object Name	PracticeVO

Create view object query with below query

SELECT * FROM XX_PRACTICE_UNITS

Click on Next to Provide Bind Parameter with Name "BindBusinessId"

And click on Add View Criteria to provide Condition as shown in below screenshot.

3. After Creation of ViewObject , the very next step is to create Application Module with below nomenclature

Package Name	Demo.adf.CascadedLOVApp.model.services
ApplicationModule Name	CascadedLOVAM

Click Next and also click on next to generate CascadeLovAmImpl

Click Next to Finish the Application Module Creation Process

After creating Application Module , now next step is to Associate View Objects which we have just created to Application Module

Double Click à CascadedLOVAM

Shuttle Available View Objects to Data Model Side as shown in below image

Now Business Component creation has been completed.

4. Creation of Cascaded LOV
Its time to create a Cascaded LOV , So here we are going to use DualVO attributes for cascading attributes. Attributes BusinessUnit will be made to work as Parent Lov and Practice will be used to make it works as Child Lov.

Below steps will be used to implement to Cascaded LOV.

Double Click à DualVO à Attributes àBusinessUnit

Click on Green Plus Sign and Shuttle BusinessUnitVO to left Side

Select List Attribute "BusinessUnitId" , this List attribute will hold the values and passed as parameter
as in Child LOV query .

Display Attributes selected as "BusinessUnitName" which will display Business Unit Names if we provide " BusinessUnitId" then Business unit ids will be shown in List of Values

Click on Ok to Finish it

Lets Create Child LOV by following above process.

Double Click à DualVO à Attributes àPractice

Click on Green Plus sign , and then Push PracticeVO to Left Side

Select List List Attribute as "PracticeId"

Select Display Attribute as "PracticeName"

Click OK to Finish the Process.

5. View Accessors to Provide View criteria

View Accessors will pass relevant Attribute value to View Criteria to execute the query. So in simple words View Accessors is responsible to fetch Child Lov Values based on the Parent LOV values .

In our Case BusinessUnit is Parent LOV and which need to passed as input to ChildLOV query and which in turns fetch correct values for ChildLOV Practice.

You need to Consider "BusinessUnit" and that needs to be passed as view criteria in Practice Lov

Double Click àDualVO àView Accessors

Shuttle the PracticeVOCriteria to left and Provide Value “BusinessUnit”