Using ExecuteWithParams action

Tech stack

Implementation demonstrated in this blog is developed using JDeveloper – version 11.1.1.7.0

Use case

In this blog we are going to see how we can use the often overlooked out-of-the-box action called ExecuteWithParams. This action basically lists all the bind variables associated with your view object and you can directly pass the values to these variables form the UI action binding to filter the VO. This saves you the time of writing the trivial AM method and calling it from a bean.

To illustrate the use of this action, we will create a query based view object which will have a bind variable in its query. On the UI, we will use single instance of this VO to show different data by sending different values for the bind variable.

Implementation steps

Step 1: Create EmployeeForDeptVO which will be our query based view object.

As you can see, the VO query has a bind variable pDeptId in the where clause. Expose this VO in the application module.

That’s pretty much our model side code. Let’s see how our UI is to be implemented.

Step 2: Create a jspx page with af:panelTabbed layout having 5 tabs, one each for departments: Administration, Meeting, Purchasing, Human Resources and Shipping. Upon running the page it will look like following:

Step 3: Now we will create a task flow which will look like following:

As can be seen above, the task flow has an input parameter deptId which the task flow consumer will pass. The default activity of this task flow is the ExecuteWithParams action which we drag and drop from data controls. Before adding the action to page, a dialog will ask us to provide values for all bind variables. In our case, the bind variable is pDeptId, for which we will provide #{pageFlowScope.deptId} as the value.

So what we did here is, we created a task flow which takes department Id as input parameter and pass this input value to ExecuteWithParams. Whenever this task flow is executed, the default activity ExecuteWithParams will trigger a VO query with input department Id and populate the rows accordingly.

The next activity in the task flow is a jsff page where we simply create a read only af:table using the EmployeeForDeptVO1 instance from data controls. This will load the rows of employees populated by the default activity.

Step 4: In the jspx page we created in step 3, add the above task flow inside each of the tabs (af:showDetailItem). Since there are 5 tabs, it will have 5 task flow bindings in the page definition file of the jspx page (one instance belonging to each tab).

Select each binding and pass the department Id as per the tab in which it belongs.

The department Id values will be: Administration = 10, Marketing = 20, Purchasing = 30, Human Resources = 40 and Shipping = 50.

We are now done with the UI with one small thing to do.

Step 5: If you run the page now, you will see that all the tabs displays same data. Any idea why this is happening?

This is happening because when the page is being loaded, all the tabs are trying to execute same task flow. But since we are using single VO, the tab for which query gets executed last decides what data will display in all the other tabs. In other words, if query for Administration tab is executed last then all the tabs will display employees for Administration department. How can we fix this?

The answer is to make the execution of task flow instances for each tab conditional. That is, we would want the task flow instance belonging to Marketing tab to get executed only when we click on Marketing tab. Similarly, for every individual tab, their respective task flow should get executed only when the particular tab is clicked.

In order to achieve this, we will do following:

Step 5.1 For each individual tab (af:showDetailItem), add an af:setPropertyListener as shown below:

As can be seen above, on tab disclosure event for Administration tab, we are setting property #{pageFlowScope.disclosedTab} as “administration”. Similarly set properties for all other tabs.

Step 5.2 In page definition select individual task flow instances and set the activation properties as shown below:

Above is task flow instance for Administration tab. Since on initial page load this tab is disclosed by default, we want its task flow instance to get executed. This is why we are adding to the activation condition #{pageFlowScope.disclosedTab == null} check. For other tabs the condition will be as follows.

Step 6: You are now ready to run and test the page :)

Alternative approach

Another approach to execute a view object with different values of query bind variables will be to expose an AM method and implement the UI side bean code to call it. In our approach we are doing the same without writing a single line of code and utilizing the ADF out of box action.

Summary

Hope you enjoyed this little blog. Until next time, live long, prosper and… Happy Coding!

Download the demo to take a look at the whole source code, which contains also some stuff, that is not explained here or just take a look at the video demonstration, in which the result is being presented.

Source Code: http://www.guardiansoftheoracleworld.com/blogs/adfman/2015/20150826_Using_execute_with_params.zip