Android SDK reference

Overview

This reference guide documents all of the methods available in the Android SDK, and explains in detail how these methods work. LaunchDarkly's SDKs are open source. The source is available in GitHub or the generated Javadocs. You can also try this SDK out by cloning and running a sample application that uses this SDK.

Getting started

After you complete the Getting Started process, follow these instructions to start using the LaunchDarkly SDK in your Android application.

To get started, declare a dependency on the LaunchDarkly Android SDK:

1implementation 'com.launchdarkly:launchdarkly-android-client-sdk:3.1.1'
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The SDK uses AndroidX from Jetpack. For projects not currently using AndroidX, a migration guide is available here.

Next, import the LaunchDarkly client in your application code:

1import com.launchdarkly.sdk.*;
2import com.launchdarkly.sdk.android.*;
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Once the SDK is installed, create a single, shared instance of LDClient. This authorizes your application to connect to LaunchDarkly and retrieve flag values for your application and environment. To create a client instance, you need your environment's mobile key, available in the Projects tab of your account settings page. Be sure to use a mobile key. Never embed a server-side SDK key into a mobile application.

The following example shows the simplest way to create the client. It will block for up to five seconds until the latest feature flags are retrieved from LaunchDarkly.

Here is how to create the client:

1LDConfig ldConfig = new LDConfig.Builder()
2    .mobileKey("YOUR_MOBILE_KEY")
3    .build();
4
5LDUser user = new LDUser.Builder("user key")
6    .email("fake@example.com")
7    .build();
8
9LDClient client = LDClient.init(this.getApplication(), ldConfig, user, 5);
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However, calling blocking code from the main thread in an Android app is not a best practice. The preferred method is shown below. It allows you to use the client immediately. Flags from the previous launch of the app are stored on the device and retrieved for immediate use. The client still connects in the background and continually updates itself with the latest flags.

Here is the preferred method:

1LDClient client = LDClient.init(this.getApplication(), ldConfig, user, 0);
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Using client, you can check which variation a particular user receives for a given feature flag:

1boolean showFeature = client.boolVariation(flagKey, true);
2if (showFeature) {
3    // application code to show the feature
4}
5else {
6    // the code to run if the feature is off
7}
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Lastly, shut down the client when your application terminates. To learn more, read Shutting down.

Data collection

To learn more about data collection within this SDK and implications on submissions to the Apple App Store, read Apple App Store data collection policy.

Supported features

This SDK supports the following features:

• Aliasing users
• Configuration
• Evaluating flags
• Flag evaluation reasons
• Flushing events
• Getting all flags
• Identifying and changing users
• Logging configuration
• Monitoring SDK status
• Multiple environments
• Offline mode
• Sending custom events
• Shutting down
• Subscribing to flag changes
• User configuration