The Screenlets that come with Liferay Screens cover common use cases for mobile apps that use Liferay. They authenticate users, interact with Dynamic Data Lists, view assets, and more. However, what if there’s no Screenlet for your specific use case? No sweat! You can create your own. Extensibility is a key strength of Liferay Screens.
This tutorial explains how to create your own Screenlets. As an example, it references code from the sample Add Bookmark Screenlet, that saves bookmarks to Liferay’s Bookmarks portlet.
In general, you use the following steps to create Screenlets:
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Determine your Screenlet’s location. Where you create your Screenlet depends on how you’ll use it.
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Create the Screenlet’s UI (its View). Although this tutorial presents all the information you need to create a View for your Screenlet, you may first want to learn how to create a View. For more information on Views in general, see the tutorial on using Views with Screenlets.
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Create the Screenlet’s Interactor. Interactors are Screenlet components that make server calls.
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Define the Screenlet’s attributes. These are the XML attributes the app developer can set when inserting the Screenlet’s XML. These attributes control aspects of the Screenlet’s behavior. You’ll add functionality to these attributes in the Screenlet class.
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Create the Screenlet class. The Screenlet class is the Screenlet’s central component. It controls the Screenlet’s behavior and is the component the app developer interacts with when inserting a Screenlet.
To understand the components that make up a Screenlet, you should first learn the architecture of Liferay Screens for Android.
Without further ado, let the Screenlet creation begin!
Determining Your Screenlet’s Location
Where you should create your Screenlet depends on how you plan to use it. If you don’t plan to reuse your Screenlet in another app or don’t want to redistribute it, create it in a new package inside your Android app project. This lets you reference and access Liferay Screens’s core, in addition to all the View Sets you may have imported.
If you want to reuse your Screenlet in another app, create it in a new Android application module. The tutorial Packaging Android Screenlets explains how to do this. When your Screenlet’s project is in place, you can start by creating the Screenlet’s UI.