There are two types of development in ADF development using jdeveloper. ui-first approach and data-first approach.
ui-first approach – design the UI first and then the data
data-first approach – design the data first and then design the UI accordingly.
In the first approach, we are sure that its very hard to design a real-time web application without some data. For this purpose adf provides a placeholder datacontrol using which we can design the page accordingly. The placeholder datacontrol is a simulation of actual data control in realtime scenario and we have full options to design the page without the actual data using this.
To start with,
In the Application Navigator, right-click the project and choose New
In the New Gallery, expand Business Tier, select Data Controls and then Placeholder Data Control, and click OK
Enter the values for place holder name, Directory name, Description and click ok
Datacontrol.dcx, adfm.xml, placeHolder.xml file gets created
Now, right-click the created datacontrol in the panel and select ‘Create Placeholder data type‘
create the attributes and click ok
The created datacontrol is exposed in the panel like a normal datacontrol
The attributes that are exposed can be dragged and dropped to the page as usual