Forms and Action URLs

Building the Web Front-End/p>

Step 8 of 11

Recall that portlets run in a portion of a page, and a page can contain multiple portlets. Because of this, portlets have phases of operation. Here, you’ll learn about the most important two. The first phase is the one you’ve already used: the render phase. All this means is that the portlet draws itself, using the JSPs you write for it.

The other phase is called the action phase. This phase runs once, when a user triggers a portlet action. The portlet performs whatever action the user triggered, such as performing a search or adding a record to a database. Then the portlet goes back to the render phase and re-renders itself according to its new state.

Action URLs

To save a guestbook entry, you must trigger a portlet action. For this, you’ll create an action URL.

Add the following tag in edit_entry.jsp after the closing </portlet:renderURL> tag:

<portlet:actionURL name="addEntry" var="addEntryURL" />

You now have the two required URLs for your form.

Forms

The form for creating guestbook entries has three fields: one for the name of the person submitting the entry, one for the person’s email address, and one for the entry itself.

Add the following tags to the end of your edit_entry.jsp file:

<aui:form action="<%= addEntryURL %>" name="<portlet:namespace />fm">

<aui:model-context bean="<%= entry %>" model="<%= GuestbookEntry.class %>" />

	<aui:fieldset>

		<aui:input name="name" />
		<aui:input name="email" />
		<aui:input name="message" />
		<aui:input name="entryId" type="hidden" />
		<aui:input name="guestbookId" type="hidden" value='<%= entry == null ? guestbookId : entry.getGuestbookId() %>'/>

	</aui:fieldset>

	<aui:button-row>

		<aui:button type="submit"></aui:button>
		<aui:button type="cancel" onClick="<%= viewURL.toString() %>"></aui:button>

	</aui:button-row>
</aui:form>

Liferay uses its Alloy UI tag library to create forms.

Save edit_entry.jsp and redeploy your application. If you refresh the page and click the Add Entry button, your form appears. If you click the Cancel button, you go back to view.jsp, but don’t try the Save button yet. You haven’t yet created the action that saves a guestbook entry, so clicking Save produces an error.

Figure 1: This is the Guestbook application's form for adding entries.

Implementing portlet actions (what happens when the user clicks Save or Delete) is your next task.