JDev 12.1.3: Use Default Activity Instead of the Deprecated Invoke Action

Since JDeveloper 12.1.3 the invoke action used in earlier version has been deprecated. Users still using the old invoke action to load data on page load should migrate their code to using the default activity in a bounded task flow instead. This article describes how to use the executeWithParams method as a default activity in a bounded task flow (btf) to load data to be shown in a region. For this we implement a common

Use Case:
in a text field the user enters a string which should be used to look-up data in the DB and show the data as a table in a region.
For this we use the HR schema and build a look-up for locations after the name of the city of the location. In a page the user can insert the name or part of a cities name into a text field. This input is send as parameter to a bounded task flow. The default activity of the btf calls a method in the view object which uses a view criteria to search for cities starting with the given input data. In a second implementation the same technique is used but a where clause is used in the VO and the VO is called with executeWithParams. The result of the search is displayed as a table in a region.

Implementation

Model Project:
We start by creating a new ‘Fusion Web Application’ and creating a model project of the HR DB schema. Here we only use the location table for which we create entity object and view object.
Now we create the view criteria which we use to find locations by part of the city name.

Next step is to create the java class for the view object including the method to safely access the created bind variable. In the class we add a method to apply the created view criteria which we expose in the client interface well as the methods to access bind variables.


Finally we have to make sure that the locations view object is part of the data model of the application module.
Resulting Application Module Data Model

Resulting Application Module Data Model


Next we add another view object to the data model which we use to implement the use case a second time. This time we use the view criteria we defined in the view object LocationsView and select it as the default where clause.

ViewController Project:
We start implementing the view controller project by first adding a start page, ‘Start’, to the unbounded task flow in adfc-config.xml. For this page we use a quick layout (One Column, Header stretched).

After opening the page (which creates it) we add a third grid row to the panelGridLayout we got from the quick layout which later holds the result table. In the first grid row we add a captain for the page, ‘Execute with param sample’, the second grid row we add an af:inputText which holds the users input for the city name to search for.
The page looks like

<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE html>
<f:view xmlns:f="http://java.sun.com/jsf/core" xmlns:af="http://xmlns.oracle.com/adf/faces/rich">
    <af:document title="Start.jsf" id="d1">
        <af:form id="f1">
            <af:panelGridLayout id="pgl1">
                <af:gridRow height="50px" id="gr1">
                    <af:gridCell width="100%" halign="stretch" valign="stretch" id="gc1">
                        <!-- Header -->
                        <af:outputText value="ExecuteWithParams Test" id="ot1" inlineStyle="font-size:x-large;"/>
                    </af:gridCell>
                </af:gridRow>
                <af:gridRow height="50px" id="gr2">
                    <af:gridCell width="100%" halign="stretch" valign="stretch" id="gc2">
                        <!-- Content -->
                        <af:inputText label="City" id="it1" value="" autoSubmit="true"/>
                    </af:gridCell>
                </af:gridRow>
                <af:gridRow id="gr3">
                    <af:gridCell id="gc3">
                        <!-- REGION HERE -->
                    </af:gridCell>
                </af:gridRow>
            </af:panelGridLayout>
        </af:form>
    </af:document>
</f:view>

Now we create a pageDefinition for the page, where we define a variable and an attribute binding which holds the users input into the inputText we added to a grid row below the header.


The final inputText look like

<af:inputText label="City" id="it1" value="#{bindings.searchCityName1.inputValue}" autoSubmit="true"/>

As you see we set the autoSubmit property to true as we don’t have (and need) a button to submit the data to the binding layer.

The next task is to create a new bounded task flow which has one input parameter, which is used to search for locations with cities starting with the given parameter from the inputText component.

Once the bounded task flow is created we can drag this btf onto the start page and drop it in the girdCell in the third gridRow and wire the parameter for the task flow to the value we have stored in the in the variable iterator via the inputText.

Finally we make the region refresh whenever the inputParamter of the task flow changes by setting the regions refresh property to ‘ifNeeded’.
The final ‘Start’ page layout looks like

<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE html>
<f:view xmlns:f="http://java.sun.com/jsf/core" xmlns:af="http://xmlns.oracle.com/adf/faces/rich">
    <af:document title="Start.jsf" id="d1">
        <af:form id="f1">
            <af:panelGridLayout id="pgl1">
                <af:gridRow height="50px" id="gr1">
                    <af:gridCell width="100%" halign="stretch" valign="stretch" id="gc1">
                        <!-- Header -->
                        <af:outputText value="ExecuteWithParams Test" id="ot1" inlineStyle="font-size:x-large;"/>
                    </af:gridCell>
                </af:gridRow>
                <af:gridRow height="50px" id="gr2">
                    <af:gridCell width="100%" halign="stretch" valign="stretch" id="gc2">
                        <!-- Content -->
                        <af:inputText label="City" id="it1" value="#{bindings.searchCityName1.inputValue}" autoSubmit="true"/>
                    </af:gridCell>
                </af:gridRow>
                <af:gridRow id="gr3">
                    <af:gridCell id="gc3">
                        <af:region value="#{bindings.showlocatiobycitybtf1.regionModel}" id="r1"/>
                    </af:gridCell>
                </af:gridRow>
            </af:panelGridLayout>
        </af:form>
    </af:document>
</f:view>

This concludes the first implementation and we can run the application

The sample application can be downloaded form ADFEMG Sample Project. It contains a second page (Start2) which uses the other view object (LocationsWithParamsView) inside the region. It’s build like the first version. The difference is that the default activity nor is the executeWithParams from the VOs operations instead the self implemented method from the VO. You spare writing the method and exposing the method in the client interface this way.
Be aware that the sample uses the HR DB schema and you have to change the connection information to point to your DB.