Set Up for Platform Development with Kotlin Android Apps

1. In your browser, go to the Meta Horizon Developer Dashboard⁠.
2. From the left-side navigation, click My Apps.
3. Choose your app from the list of apps.
4. From the left-side navigation, click Development > API. You’ll find your App ID in the middle of the API page. You’ll need your App ID to call the initialization APIs described in the next few sections.
5. From the left-side navigation, click Distribution > Builds.
6. Open any build from the list of builds. You’ll find your Package Name in the middle of the Build Details page.

1. Open Android Studio
2. Select File > New > New Project
3. Select the “Empty Activity” template
4. Click “Next”
5. Fill the Project Settings
   • In Name, input a value such as “notification”
   • In Package Name, input the value from Prerequisites, such as “horizon.platform.sample.notification”
   • In Minimum SDK, select API 35 Android 15.0
   • In Build configuration language, select Kotlin DSL
6. Click Finish
7. Wait a few seconds until the project creation is completed
8. In the top left, there is a dropdown menu with Android as current value, select Project so you can see all the files in the project

1. Open the file ./gradle/libs.versions.toml
   • In the versions section, replace the version of the following libraries:

   [versions]
   // Find and Replace the version of the following libraries:
   activityCompose = "1.9.3"
   coreKtx = "1.13.1"
   kotlin = "2.1.0"
   
   • In the plugins section, add the compose compiler plugin

   [plugins]
   // Existing lines
   kotlin-compose = { id = "org.jetbrains.kotlin.plugin.compose", version.ref = "kotlin" }
   
2. Open the file ./build.gradle.kts. In the plugins section, add the compose compiler plugin

   plugins {
       // Existing lines
       alias(libs.plugins.kotlin.compose) apply false
   }
   
3. Open the file ./app/build.gradle.kts. In the plugins section, add the compose compiler plugin

   plugins {
       // Existing lines
       alias(libs.plugins.kotlin.compose)
   }
   
4. In the menu bar, select File, Sync Project with Gradle Files
5. In the menu bar, select Build, Generate App Bundles or APKs, Generate APKs

1. Open the file ./settings.gradle.kts. In the section dependencyResolutionManagement.repositories, add mavenCentral(). It should look similar to:

   dependencyResolutionManagement {
       repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
       repositories {
           google()
           mavenCentral()
       }
   }
   
2. Open the file ./gradle/libs.versions.toml
   • In the versions section, add the line below to set the SDK version

   [versions]
   // Existing lines
   horizonPlatformSdk = "0.2.0"
   
   • In the libraries section, add the SDK libraries

   [libraries]
   // Existing lines
   core-kotlin = { module = "com.meta.horizon.platform.sdk:core-kotlin", version.ref = "horizonPlatformSdk" }
   
3. Open the file app/build.gradle.kts. In the dependencies section, add the SDK libraries. It should look similar to:

   dependencies {
       // Existing lines
       implementation(libs.core.kotlin)
   }
   
4. In the menu bar, select File, Sync Project with Gradle Files
5. In the menu bar, select Build, Generate App Bundles or APKs, Generate APKs
6. In the left panel, expand the “External Libraries” section and you should see the SDK dependencies listed
   • com.meta.horizon.platform.sdk:core-kotlin

1. Open the file MainActivity.kt
   • Add imports

   import android.content.Context
   import android.util.Log
   import horizon.core.android.driver.coroutines.HorizonServiceConnection
   import kotlinx.coroutines.coroutineScope
   import kotlinx.coroutines.runBlocking
   
   • Add this content and set the correct value in APPLICATION_ID

   fun onCreatePlatformSDK(context: Context) = runBlocking {
       initPlatformSDK(context)
   }
   
   suspend fun initPlatformSDK(context: Context) = coroutineScope {
       val TAG = "MainActivity"
       val APPLICATION_ID = "FILL_APP_ID"
       try {
           Log.i(TAG, "Connecting to Horizon Service with valid app id")
           HorizonServiceConnection.connect(APPLICATION_ID, context)
           Log.i(TAG, "PlatformSDK is ready!")
       } catch (e: Exception) {
           Log.e(TAG, "logging Exception", e)
       } catch (e: NoClassDefFoundError) {
           Log.e(TAG, "logging NoClassDefFoundError", e)
       }
   }
   
   • Find the line “override fun onCreate”, add this content to the bottom of the function body

   onCreatePlatformSDK(this@MainActivity.applicationContext)
   
   • Find the line “import horizon.core.android.driver.coroutines.HorizonServiceConnection”. You can hover over the class name “HorizonServiceConnection” and the package name “coroutines” to see the JavaDoc contents
2. In the menu bar, select Build, Generate App Bundles or APKs, Generate APKs

1. Connect the headset to the computer using USB-C cable
2. In the menu bar, select Build, Generate App Bundles or APKs, Generate APKs
3. Open an Android Studio terminal
4. Install the app

   adb install ./app/build/outputs/apk/debug/app-debug.apk
   
5. Start the app

   APP_PACKAGE_NAME=horizon.platform.sample.notification
   adb shell am start-activity -n "$APP_PACKAGE_NAME/.MainActivity"
   
6. Review logcat, you should see similar content

   14:21:51.972 MainActivity             I  Connecting to Horizon Service with valid app id
   14:21:51.998 HzServiceConnection      D  Horizon Platform connection: Start
   14:21:52.000 HzServiceConnection      D  Horizon Platform connection initialization state: horizon.core.android.driver.coroutines.HorizonServiceConnection$InitializationStage$Uninitialized@a71c274
   14:21:52.000 HzServiceConnection      D  Horizon Platform connection starting
   14:21:52.008 MainActivity             I  PlatformSDK is ready!
   14:21:52.047 HzServiceConnection      D  Horizon Platform connection created, getting global session id
   14:21:52.048 HzServiceConnection      D  Horizon Platform connection success!
   14:21:52.048 HzServiceConnection      D  Horizon Platform connection initialization state: horizon.core.android.driver.coroutines.HorizonServiceConnection$InitializationStage$Connected@3564b79
   
7. Stop the app

   APP_PACKAGE_NAME=horizon.platform.sample.notification
   adb shell am force-stop "$APP_PACKAGE_NAME"
   

• Application
• Application lifecycle
• Group presence
• In-app purchase
• Leaderboards
• User age category
• Users