Add the open subtitles API key from the gradle properties

application/resources/build.gradle

@@ -15,6 +15,7 @@ android {
         compileSdk rootProject.ext.compileSdkVersion
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
         buildConfigField "String", "APP_ID", "\"${rootProject.ext.appId}\""
+        buildConfigField 'String', 'VLC_OPEN_SUBTITLES_API_KEY', "\"${getOSApiKey(project)}\""
         vectorDrawables.useSupportLibrary = true
     }
 
@@ -53,6 +54,11 @@ android {
     }
 
 }
+
+static def getOSApiKey(project) {
+    return System.getenv('VLC_OPEN_SUBTITLES_API_KEY') ?:  project.properties['vlc_open_subtitles_api_key'] ?: ""
+}
+
 dependencies {
     api "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
     api 'androidx.multidex:multidex:2.0.1'