Include open source notices

Google Play services sometimes includes, or depends upon, open source libraries. To comply with the license requirements of open source libraries, you as a developer are responsible for appropriately displaying the notices for the open source libraries that your app uses.

Google Play services includes a set of tools designed to give developers an easier way to express the open source software notices of libraries used in their apps. One of these tools is a Gradle plugin that collects license terms from included libraries, as declared in their POM files, and creates an activity that can be used to display these terms. Learn more about how the tool finds and packages license information.

Add the Gradle plugin

In your root-level build file, do the following:

1. Include the Google Maven repository.
2. Add the oss-licenses plugin to your dependencies.

The following code snippet shows these steps:

Kotlin DSL

build.gradle.kts

buildscript {
  repositories {
    ...
    google()  // maven { url("https://maven.google.com") } for Gradle <= 3
  }
  dependencies {
    ...
    classpath("com.google.android.gms:oss-licenses-plugin:0.10.6")
  }
}

Groovy DSL

build.gradle

buildscript {
  repositories {
    ...
    google()  // maven { url "https://maven.google.com" } for Gradle <= 3
  }
  dependencies {
    ...
    classpath 'com.google.android.gms:oss-licenses-plugin:0.10.6'
  }
}

In your app-level build file, apply the plugin by adding the following line under the existing declaration of the com.android.application plugin at the top of the file:

Kotlin DSL

app/build.gradle.kts

plugins {
    id("com.android.application")
    id("com.google.android.gms.oss-licenses-plugin")
}

Groovy DSL

app/build.gradle

plugins {
    id 'com.android.application'
    id 'com.google.android.gms.oss-licenses-plugin'
}

You can view the code for this plugin on GitHub.

Add the library to your app

In the dependencies section of your app-level build file, add a dependency on theoss-licenses library:

Kotlin DSL

build.gradle.kts

implementation("com.google.android.gms:play-services-oss-licenses:17.0.1")

Groovy DSL

build.gradle

implementation 'com.google.android.gms:play-services-oss-licenses:17.0.1'

Display license information

When your app builds, the Gradle plugin processes the licenses and adds them to your app's resources. To easily display the license, you can launch an activity that's provided by the play-services-oss-licenses library at an appropriate point in your app, as shown in the following code snippet:

Kotlin

import com.google.android.gms.oss.licenses.OssLicensesMenuActivity
...

// When the user selects an option to see the licenses:
startActivity(Intent(this, OssLicensesMenuActivity::class.java))

Java

import com.google.android.gms.oss.licenses.OssLicensesMenuActivity;
...

// When the user selects an option to see the licenses:
startActivity(new Intent(this, OssLicensesMenuActivity.class));

When launched, this activity display a list of open source libraries that are compiled into your app, including the libraries that are a part of Google Play services, as shown in figure 1. Users can tap on the name of a library to view additional license information for that library.

Figure 1. The licenses menu activity shows a selectable list of open source libraries that an app uses.

Set the activity title

By default, the displayed activity has the title "Open source licenses". You can customize the title of the activity by calling setActivityTitle(), as shown in the following code snippet:

Kotlin

OssLicensesMenuActivity.setActivityTitle(getString(R.string.custom_license_title))

Java

OssLicensesMenuActivity.setActivityTitle(getString(R.string.custom_license_title));

Apply a theme to the activity

You can apply a theme to the activity to match the theme used in your app's other activities. To do so, include the open source license activity in an <activity> element within your app's manifest file, as shown in the following code snippet:

<application android:theme="@style/AppTheme" ...>
    <activity
        android:name="com.google.android.gms.oss.licenses.OssLicensesMenuActivity"
        android:theme="@style/AppTheme" />
    <activity
        android:name="com.google.android.gms.oss.licenses.OssLicensesActivity"
        android:theme="@style/AppTheme" />
</application>

How the list of licenses is determined

At compile time, the Gradle plugin scans the POM dependencies of your app's project. When a Maven POM exists for a direct dependency of the app, the plugin processes each <licenses> element and embeds the link and title of each license in an Android asset that's included with your app.

Note: The list of licenses also includes the full license text of any library that is depended upon by the transitive closure of Google Play services libraries used by the app. This means that the list includes any open source libraries that are used to create the Google Play services libraries that are compiled into your app.