Creating iOS List Screenlets

It’s very common for mobile apps to display lists. Liferay Screens lets you display asset lists and DDL lists in your iOS app by using Asset List Screenlet and DDL List Screenlet, respectively. Screens also includes list Screenlets for displaying lists of other Liferay entities like web content articles, images, and more. The Screenlet reference documentation lists all the Screenlets included with Liferay Screens. If there’s not a list Screenlet for the entity you want to display in a list, you must create your own list Screenlet. A list Screenlet can display any entity from a Liferay instance. For example, you can create a list Screenlet that displays standard Liferay entities like User, or custom entities from custom Liferay apps.

The tutorials in this section use code from the sample Bookmark List Screenlet to show you how to create your own list Screenlet. This Screenlet displays a list of bookmarks from Liferay’s Bookmarks portlet. You can find this Screenlet’s complete code here in GitHub.

Note that because this tutorial focuses on creating a list Screenlet, it doesn’t explain general Screenlet concepts and components. Before beginning, you should therefore read the following:

• Creating iOS Screenlets
• Supporting Multiple Themes in Your Screenlet
• Create and Use a Connector with Your Screenlet
• Add a Screenlet Delegate
• Creating and Using Your Screenlet’s Model Class

You’ll create a list Screenlet by following these steps:

1. Creating the Model class
2. Creating the Theme
3. Creating the Connector
4. Creating the Interactor
5. Creating the Delegate
6. Creating the Screenlet class

First though, you should understand how pagination works with list Screenlets.

Pagination

To ensure that users can scroll smoothly through large lists of items, list Screenlets support fluent pagination. Support for this is built into the list Screenlet framework. You’ll see this as you construct your list Screenlet.

Creating the Model Class

Recall that a model class transforms each [String:AnyObject] entity Screens receives into a model object that represents the corresponding Liferay entity. For instructions on creating your model class, see the tutorial Creating and Using Your Screenlet’s Model Class. The example model class in that tutorial is identical to Bookmark List Screenlet’s.

Next, you’ll create your list Screenlet’s theme.

« Creating the iOS Screenlet's ClassCreating the iOS List Screenlet's Theme »