How to fire a entity level validation on an attribute change in ADF BC?

by default JDeveloper allows you to select the attributes that trigger validation, so that validation execution happens only when one of the triggering attributes is dirty.In previous releases of JDeveloper, an entity-level validator would fire on an attribute whenever the entity as a whole was dirty.

Specifying the attributes which when changed trigger the entity level validation

1. Create the entity level validation with the required rule type
2. Go to the Validation execution tab to select the condition when the rule should be fired. This is the place where we should select if changes to a particular attribute should fire the current business rule. 
3. This is shown in the below image 

1. We can select more then one attribute in the triggering attributes dialog.
2. Firing execution only when required makes your application more performant.

How to programmatically navigate in ADF?

Sometimes we might need to programmatically execute the navigation and redirect to another page in Oracle ADF. This can be done in two ways

Approach #1

Get the navigation handler handle from the application context and pass the appropriate arguments to that. A sample code to achieve the same is as below.

import javax.faces.context.FacesContext;
import javax.faces.application.Application;
import javax.faces.application.NavigationHandler;

public void handleNavigation() {
    FacesContext context = FacesContext.getCurrentInstance();
    Application app = context.getApplication();
    NavigationHandler handler = app.getNavigationHandler();
    handler.handleNavigation(context, null, "navigation-action");
}

If you see the signature of the handleNavigation method, it is as below

public abstract void handleNavigation(FacesContext context,
                                      String fromAction,
                                      String outcome)

Approach #2

1. Have a command button with action set on it.
2. Make the visible property of the button false. 
3. Programmatically execute the action of the button to navigate to the required page. In this way we hide the button and achieve the navigation. The sample code for the same is as below

import javax.faces.context.FacesContext;
import javax.faces.component.UIViewRoot;
import javax.faces.event.ActionEvent;
import oracle.adf.view.rich.component.rich.nav.RichCommandButton;

public void handleNavigation() {
  FacesContext facesContext = FacesContext.getCurrentInstance();
  UIViewRoot root = facesContext.getViewRoot();
  RichCommandButton button = (RichCommandButton) root.findComponent("button-id");
  ActionEvent actionEvent = new ActionEvent(button);
  actionEvent.queue();
}

Get the button pressed on af:dialog in the managed bean in ADF?

For this scenario let us assume that we are handling a dialog with three buttons Yes, No and Cancel as shown below

Step1

In this step bind the DialogListener of the af:dialog to the managed bean method which will be executed on clicking any button on the dialog. This can be configured as shown below from the property inspector.

Step2

get the button pressed as shown in the below code and perform the respective action.

import oracle.adf.view.rich.event.DialogEvent.Outcome;
import oracle.adf.view.rich.event.DialogEvent;

public void onDialogButtonPress(DialogEvent dialogEvent) {
Outcome dialogOutcome = dialogEvent.getOutcome();

if(dialogOutcome == Outcome.yes) {

}
else if (dialogOutcome == Outcome.no) {

}
else if (dialogOutcome == Outcome.cancel) {

}
}

Note:  The cancel event is deprecated and should be handled at the client side or invoke the server side event from client side. I shall explain this in another post.

How to get the view object instance in the managed bean from pagedef file in Oracle ADF?

Sometimes during the implementation of Oracle ADF applications we might need programmatic access to the underlying View Object. It is not advisable to create the instance of the ADF model business components directly.

We can get the view Object from the iterator in the pagedef file of the corresponding page or page fragment. If suppose the iterator is as shown in the below diagram.

The following code will get the view object from the Iterator.

How to get auto complete in editing css files for Oracle ADF skinning?

By default whenever we type anything in the editor, we get the auto complete option from the JDeveloper. It is not the case for editing the css files using the JDeveloper. We have to enable the supported components option as shown below to get the auto complete.

go to tools -> preferences -> CSS Editor. Enable the checkbox "ADF Faces Extension"

Once done we get the auto complete options in writing the skin selectors in the css file. This is a very useful tip and avoids the user to remember the skin selectors.

How to create deploy and reuse the taskflow/datacontrol as a library in Oracle ADF application? How to Reuse taskflow of one application in another in ADF?

Many a times we might need to use the taskflow or datacontrol of one ADF application in another. For example if there is an application module with much of business functionality then we might want to reuse the entire AM in another application. This can be achieved in many ways. One way is to create a library out of the ADF application and deploy it and reuse it as an artifact in another application. The following approach explains this.

Step1: Create the library out of ViewController project application

1. Double click the view controller project
2. In the project properties dialog, click the Deployment section
3. Create a new deployment profile by clicking the New option
4. In the archive type select the ADF library jar file as shown below

ADF libraries is a Java Archive (JAR) file concept in ADF that contains a specific manifest file that allow Oracle JDeveloper to detect and import reusable components so they show in the ADF Component palette.

Step2: Deploy the taskflow/UI project using the newly created deployment profile

Now that we have created the deployment profile, we will deploy the project and its artifacts as the ADF library so that it can be imported and used in another application. Deployment is done as below

Step3: Import the deployment in another application

1. Create the file system connection in the resource palette to point to that directory as shown below. Give some connection name and in the directory path, point to the jar file deployed directory 
2. Select the deployment and say add to the project as shown below.

1.  
2. On doing that we observe the new data control and the new connection are also imported to the current project. 
3. We can thus use the service methods from the imported data control
4. We can also observe in the below image about how to import the region from the imported library from the component palette

One important thing to note is the naming convention here. If the package names are same in the imported library and the current project then we will have the naming conflicts and the fucntionality will not work as expected. The better naming convention is to com.project_name.resource_package

How to implement skinning in Oracle ADF ?

In order to implement the skinning we need to configure three files in oracle ADF.

1. trinidad-skins.xml by default this file is not present on creating the Oracle ADF fusion application. We have to create this file in the WEB-INF directory. This is the file where we register and configure all the available for this application. For each skin we have several properties to be configured. A sample trinidad-skins.xml looks as below.


<?xml version="1.0" encoding="windows-1252" ?>
<skins xmlns="http://myfaces.apache.org/trinidad/skin">
 <skin>
<id>custom.skin.adf.app</id>
<family>MyApplicationSkin</family>
<extends>blafplus-rich.desktop</extends>
<render-kit-id>org.apache.myfaces.trinidad.desktop</render-kit-id>
<style-sheet-name>css/myapp-layout.css</style-sheet-name>
 </skin>
</skins>





trinidad-config.xml: If there are more than one skin defined in the trinidad-skins.xml, then we can choose one of them to be active on the current application. This is the file where we specify the skin that is applied in the current application.


<?xml version="1.0" encoding="windows-1252" ?>
<trinidad-config xmlns="http://myfaces.apache.org/trinidad/config">
  <skin-family>MyApplicationSkin</skin-family>
  <skin-version>v1.2</skin-version>
</trinidad-config> 

css file: This is file where define the look and feel of each and every component. We have to use and identify various ADF skin selectors mentioned in this link.

 By default in the adf application we create, the fusion skin is applied and the look and feel is as below.

After applying selectors and modifying the myapp-layout.css file the look may be as below.

How to get Locale/Language in ADF BC, ADF Faces and using Expression language - Oracle ADF

Many times we might need get the locale of the user and may be manipulate the skins or business logic based on that. By default, ADF Faces determines the locale of the end user by inspecting the browser language settings.

Get the locale in ADF Business Components Java Class

import java.util.Locale;
import oracle.adf.share.ADFContext;

Locale locale = ADFContext.getCurrent().adfctx.getLocale();

Get the locale in ADF Managed Bean

import java.util.Locale;
import javax.faces.context.FacesContext;

Locale locale = FacesContext.getCurrentInstance().getViewRoot().getLocale();

Get the locale using expression language

#{facesContext.ViewRoot.locale.language}

Once we get the locale, we can get the user language using either of the below methods

1. String userLang = locale.getLanguage();
2. #{facesContext.ViewRoot.locale.language}

javax.el.ELException: oracle.adfinternal.controller.savepoint.SavePointException: ADFC-08011: Oracle ADF

Sometimes we get the following error when working with oracle ADF

javax.el.ELException: oracle.adfinternal.controller.savepoint.SavePointException: ADFC-08011: The JNDI connection name is not specified in configuration file adf-config.xml.

This is because the data source is not configured in the adf-config.xml which tells the framework the place the store the current snapshot of the application

it can be done as shown in my previous blog step1

oracle.jbo.JboException: JBO-34010: The "view/DataBindings.cpx" descriptor appears in the application classpath more than once:

The above error occurs when the current project under development is including an external library (May be another ADF application). There can be package name conflicts which is causing this issue. The databindings.cpx is present in the same package (folder structure) in the imported library and the current package.

Best practice is to use the unique names often starting the package name with the short form of the current application.