Defining the Component Metadata Properties

Building the Web Front-End

Step 2 of 11

When users add applications to a page, they pick them from a list of display categories.

Figure 1: Users choose applications from a list of display categories.

A portlet’s display category is defined in its component class as a metadata property. Since the Guestbook portlet lets users communicate with each other, you’ll add it to the Social category. Only one Guestbook portlet should be added to a page, so you’ll also define it as a non-instanceable portlet. Such a portlet can appear only once on a page or Site, depending on its scope.

1. Open the GuestbookPortlet class and update the component class metadata properties to match this configuration:

   @Component(
       immediate = true,
       property = {
         "com.liferay.portlet.display-category=category.social",
         "com.liferay.portlet.instanceable=false",
         "com.liferay.portlet.scopeable=true",
         "javax.portlet.display-name=Guestbook",
         "javax.portlet.expiration-cache=0",
         "javax.portlet.init-param.template-path=/",
         "javax.portlet.init-param.view-template=/guestbook/view.jsp",
         "javax.portlet.resource-bundle=content.Language",
         "javax.portlet.security-role-ref=power-user,user",
         "javax.portlet.supports.mime-type=text/html"
       },
       service = Portlet.class
   )
   

The com.liferay.portlet.display-category=category.social property sets the Guestbook portlet’s display category to Social. The com.liferay.portlet.instanceable=false property specifies that the Guestbook portlet is non-instanceable, so only one instance of the portlet can be added to a page. In the property javax.portlet.init-param.view-template, you also update the location of the main view.jsp to a folder in src/main/resources/META-INF/resources called /guestbook. You’ll wind up creating two folders there for the two different portlets you’ll create: guestbook and guestbook-admin. For now, just create the guestbook folder:

1. Open src/main/resources, then open META-INF. Right-click on the resources folder and select New → Folder.

2. Name the folder guestbook and hit Enter (or click OK).

3. Drag view.jsp and drop it onto the guestbook folder to move it there.

4. Open view.jsp and modify the path to init.jsp to include it from the parent folder:

   <%@ include file="../init.jsp" %>
   

Since you edited the portlet’s metadata, you must remove and re-add the portlet to the page before continuing:

1. Go to localhost:8080 in your web browser.

2. Sign in to your administrative account.

3. The Guestbook portlet now shows an error on the page. Click its portlet menu (at the top-right of the portlet), then select Remove and click OK to confirm.

4. Open the Add menu and select Widgets.

5. Open the Social category and drag and drop the Guestbook widget onto the page.

Great! Now the Guestbook portlet appears in an appropriate category. Though you were able to add it to the page before, the user experience is better.