Rating Screenlet for Android

Requirements

• Android SDK 4.1 (API Level 16) or above
• Liferay Portal 6.2 CE/EE, Liferay CE Portal 7.0/7.1, Liferay DXP 7.0+
• Liferay Screens Compatibility app (CE or EE/DXP). This app is preinstalled in Liferay CE Portal 7.0/7.1 and Liferay DXP 7.0+.

Compatibility

• Android SDK 4.1 (API Level 16) or above

Xamarin Requirements

• Visual Studio 7.2
• Mono .NET framework 5.4.1.6

Features

Rating Screenlet shows an asset’s rating. It also lets users update or delete the rating. This Screenlet comes with different Views that display ratings as thumbs, stars, and emojis.

JSON Services Used

Screenlets in Liferay Screens call JSON web services in the portal. This Screenlet calls the following services and methods.

Service	Method	Notes
ScreensratingsentryService (Screens compatibility plugin)	getRatingsEntries	With entryId
ScreensratingsentryService (Screens compatibility plugin)	getRatingsEntries	With classPK and className
ScreensratingsentryService (Screens compatibility plugin)	updateRatingsEntry
ScreensratingsentryService (Screens compatibility plugin)	deleteRatingsEntry

Module

• None

Views

The default View uses an Android RatingBar to show an asset’s rating. Other custom Views may show the rating with a different Android component such as Button, ImageButton, or others.

This Screenlet has five different Views:

1. Like
2. Thumbs (default)
3. Stars
4. Reactions
5. Emojis

Figure 1: Rating Screenlet's different Views.

Offline

This Screenlet supports offline mode so it can function without a network connection. For more information on how offline mode works, see the tutorial on its architecture. Here are the offline mode policies that you can use with this Screenlet:

Policy	What happens	When to use
REMOTE_ONLY	The Screenlet loads the data from the Liferay instance. If a connection issue occurs, the Screenlet uses the listener to notify the developer about the error. If the Screenlet successfully loads the data, it stores it in the local cache for later use.	Use this policy when you always need to show updated data, and show nothing when there’s no connection.
CACHE_ONLY	The Screenlet loads the data from the local cache. If the data isn’t there, the Screenlet uses the listener to notify the developer about the error.	Use this policy when you always need to show local data, without retrieving remote information under any circumstance.
REMOTE_FIRST	The Screenlet loads the data from the Liferay instance. If this succeeds, the Screenlet shows the data to the user and stores it in the local cache for later use. If a connection issue occurs, the Screenlet retrieves the data from the local cache. If the data doesn’t exist there, the Screenlet uses the listener to notify the developer about the error.	Use this policy to show the most recent version of the data when connected, but show an outdated version when there’s no connection.
CACHE_FIRST	The Screenlet loads the data from the local cache. If the data isn’t there, the Screenlet requests it from the Liferay instance and notifies the developer about any errors that occur (including connectivity errors).	Use this policy to save bandwidth and loading time in case you have local (but probably outdated) data.

Required Attributes

• entryId

If you don’t use entryId, you must use both of the following attributes:

• className
• classPK

Attributes

Attribute	Data type	Explanation
layoutId	@layout	The ID of the layout to use to show the View.
autoLoad	boolean	Whether the rating loads automatically when the Screenlet appears in the app’s UI. The default value is true.
editable	boolean	Whether the user can change the rating.
entryId	number	The primary key of the asset with the rating to display.
className	string	The asset’s fully qualified class name. For example, a blog entry’s className is com.liferay.blogs.kernel.model.BlogsEntry. The className attribute is required when using it with classPK to instantiate the Screenlet.
classPK	number	The asset’s unique identifier. Only use this attribute when also using className to instantiate the Screenlet.
groupId	number	The ID of the site (group) containing the asset.
cachePolicy	string	The offline mode setting. See the Offline section for details.

Methods

Method	Return	Explanation
load()	void	Starts the request to load the asset’s ratings.

Listener

Rating Screenlet delegates some events to an object or class that implements its RatingListener interface. Therefore, Rating Screenlet’s listener methods are as follows:

• onRatingOperationSuccess(AssetRating assetRating): Called when the operation finishes successfully and the rating is loaded.