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If validation in successful, the web controller then calls the FormSubmissionController handleFormSubmission(FormEntrySession, HttpServletRequest) method. Again, the FormSubmissionController iterates through all the FormSubmissionControllerActions, this time calling their handleFormSubmissionhandleSubmission(FormEntrySession, HttpServletRequest) methods to handle the submission of the individual elements in the form.

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That's a basic, but not exhaustive, overview of how the module work. We didn't discuss how obsgroups are implemented, or about the various classes in the schema package, among other things. Check out the javadocs for more information.

Other Features

Custom Tags

Custom tags can be registered by calling the HtmlFormEntryService addHandler method().  Modules can register new tags by calling this method... for an example, in the HTML Form Flowsheet module the onLoad() method in the HtmlFormFlowsheetActivator registers a handler for a new "htmlformflowsheet" tag.  To create a custom tag, you will need to define implementations of TagHandler, HtmlGeneratorElement, and FormSubmissionControllerAction for this new tag.  You can take a look at some of the existing tags for examples of how to do this.

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In the future, attribute descriptors may be used for other purposes besides metadata sharing.  For instance, the Html Form Entry Designer module could use the descriptors to determine the valid attributes for a tag.

Custom Content for Velocity Context

If your module instantiates a Spring bean that implements org.openmrs.module.htmlformentry.velocity.VelocityContextContentProvider then your bean's populateContext() method will be called each time a new HTML Form is opened (for entry, view, or edit). (Since HTML Form Entry 1.11)

See an example from the Kenya EMR module on github.