2.8 Examining the Binding Metadata Files Involved

The group of bindings supporting the UI components on a page are described in a page-specific XML file called the page definition file. The first time you drop a databound component from the Data Control Palette on a page, JDeveloper will create the page definition file for it. Figure 2-25 shows the contents of the searchtechniciansPageDef.xml file in the Structure window. Each time you add components to the page using the Data Control Palette JDeveloper adds appropriate declarative binding entries into this page definition file.

For example, after performing the steps in the previous section to create the databound UI components on the searchtechnicians.jspx page, you can see in the figure that JDeveloper added an action binding named ExecuteWithParams to invoke the built-in data control operation of the same name. Iterator bindings named TechniciansIterator and SkillsIterator were added to handle the data collection of rows from the Technicians and Skills view object instances, respectively. Action bindings named Next and Previous were added to support the buttons that were dropped. And, finally, value bindings of appropriate names were added to support the read-only outputText fields and the table.

Figure 2-25 Page Definition XML File for searchtechnicians.jspx

The very first time you perform Oracle ADF Model data binding in a project, JDeveloper creates one additional XML file called DataBindings.cpx that stores information about the mapping between page names and page definition names and that lists the data controls that are in use in the project. Figure 2-26 shows what the DataBindings.cpx file looks like in the Structure window. At runtime, this file is used to create the overall Oracle ADF Model binding context. In addition, page map and page definition information from this file are used to instantiate the binding containers for pages as they are needed by the pages the user visits in your application.

Figure 2-26 Structure of DataBindings.cpx

For complete details on the structure and contents of the DataControls.dcx, DataBindings.cpx, and PageDef.xml metadata files, see Appendix A, "Reference ADF XML Files".