Switch to getLanguages Promise on android

android/src/main/AndroidManifest.xml

@@ -1,3 +1,3 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="com.alexanderzaytsev.rn18n">
+    package="com.AlexanderZaytsev.RNI18n">
 </manifest>

android/src/main/java/com/AlexanderZaytsev/RNI18n/RNI18nModule.java

@@ -0,0 +1,60 @@
+package com.AlexanderZaytsev.RNI18n;
+
+import android.os.Build;
+import android.os.LocaleList;
+
+import com.facebook.react.bridge.Arguments;
+import com.facebook.react.bridge.Promise;
+import com.facebook.react.bridge.ReactApplicationContext;
+import com.facebook.react.bridge.ReactContextBaseJavaModule;
+import com.facebook.react.bridge.ReactMethod;
+import com.facebook.react.bridge.WritableArray;
+
+import java.util.Locale;
+
+public class RNI18nModule extends ReactContextBaseJavaModule {
+
+  public RNI18nModule(ReactApplicationContext reactContext) {
+    super(reactContext);
+  }
+
+  @Override
+  public String getName() {
+    return "RNI18n";
+  }
+
+  private String toLanguageTag(Locale locale) {
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
+      return locale.toLanguageTag();
+    }
+
+    StringBuilder builder = new StringBuilder();
+    builder.append(locale.getLanguage());
+
+    if (locale.getCountry() != null) {
+      builder.append("-");
+      builder.append(locale.getCountry());
+    }
+
+    return builder.toString();
+  }
+
+  @ReactMethod
+  public void getLanguages(Promise promise) {
+    try {
+      LocaleList locales = Build.VERSION.SDK_INT >= Build.VERSION_CODES.N
+        ? getReactApplicationContext().getResources().getConfiguration().getLocales()
+        : new LocaleList(getReactApplicationContext().getResources().getConfiguration().locale);
+
+      WritableArray languages = Arguments.createArray();
+
+      for (int i = 0; i < locales.size(); i++) {
+        languages.pushString(this.toLanguageTag(locales.get(i)));
+      }
+
+      promise.resolve(languages);
+    } catch (Exception e) {
+      promise.reject(e);
+    }
+  }
+}

android/src/main/java/com/AlexanderZaytsev/RNI18n/RNI18nPackage.java

@@ -1,4 +1,4 @@
-package com.alexanderzaytsev.rn18n;
+package com.AlexanderZaytsev.RNI18n;
 
 import com.facebook.react.ReactPackage;
 import com.facebook.react.bridge.JavaScriptModule;

android/src/main/java/com/alexanderzaytsev/rn18n/RNI18nModule.java

@@ -1,67 +0,0 @@
-package com.alexanderzaytsev.rn18n;
-
-import android.os.Build;
-import android.os.LocaleList;
-
-import com.facebook.react.bridge.Arguments;
-import com.facebook.react.bridge.WritableArray;
-import com.facebook.react.bridge.ReactApplicationContext;
-import com.facebook.react.bridge.ReactContextBaseJavaModule;
-
-import java.util.HashMap;
-import java.util.Locale;
-import java.util.Map;
-
-public class RNI18nModule extends ReactContextBaseJavaModule {
-
-  public RNI18nModule(ReactApplicationContext reactContext) {
-    super(reactContext);
-  }
-
-  @Override
-  public String getName() {
-    return "RNI18n";
-  }
-
-  private boolean isSupportingPreferredLanguages() {
-    return Build.VERSION.SDK_INT >= Build.VERSION_CODES.N;
-  }
-
-  private LocaleList getLocales() {
-    return this.isSupportingPreferredLanguages()
-      ? getReactApplicationContext().getResources().getConfiguration().getLocales()
-      : new LocaleList(getReactApplicationContext().getResources().getConfiguration().locale);
-  }
-
-  private String toLanguageTag(Locale locale) {
-    if (this.isSupportingPreferredLanguages()) {
-      return locale.toLanguageTag();
-    }
-
-    StringBuilder builder = new StringBuilder();
-    builder.append(locale.getLanguage());
-
-    if (locale.getCountry() != null) {
-      builder.append("-");
-      builder.append(locale.getCountry());
-    }
-
-    return builder.toString();
-  }
-
-  @Override
-  public Map<String, Object> getConstants() {
-    HashMap<String,Object> constants = new HashMap<String,Object>();
-    LocaleList locales = this.getLocales();
-    WritableArray languages = Arguments.createArray();
-
-    for (int i = 0; i < locales.size(); i++) {
-      languages.pushString(this.toLanguageTag(locales.get(i)));
-    }
-
-    constants.put("language", languages.getString(0));
-    constants.put("languages", languages);
-
-    return constants;
-  }
-}

example/android/app/src/main/java/com/rni18nexample/MainApplication.java

@@ -7,7 +7,8 @@ import com.facebook.react.ReactNativeHost;
 import com.facebook.react.ReactPackage;
 import com.facebook.react.shell.MainReactPackage;
 import com.facebook.soloader.SoLoader;
-import com.alexanderzaytsev.rn18n.RNI18nPackage;
+
+import com.AlexanderZaytsev.RNI18n.RNI18nPackage;
 
 import java.util.Arrays;
 import java.util.List;