[android] Add function to get all android system languages

Signed-off-by: gekeleda <git@davidgekeler.eu>

android/sdk/src/main/cpp/app/organicmaps/sdk/platform/Language.cpp

@@ -9,8 +9,7 @@
 
 #include <string>
 
-/// This function is called from native c++ code
-std::string GetAndroidSystemLanguage()
+std::vector<std::string> GetAndroidSystemLanguages()
 {
   static char const * DEFAULT_LANG = "en";
 
@@ -18,20 +17,31 @@ std::string GetAndroidSystemLanguage()
   if (!env)
   {
     LOG(LWARNING, ("Can't get JNIEnv"));
-    return DEFAULT_LANG;
+    return {DEFAULT_LANG};
   }
 
   static jclass const languageClass = jni::GetGlobalClassRef(env, "app/organicmaps/sdk/util/Language");
-  static jmethodID const getDefaultLocaleId =
-      jni::GetStaticMethodID(env, languageClass, "getDefaultLocale", "()Ljava/lang/String;");
 
-  jni::TScopedLocalRef localeRef(env, env->CallStaticObjectMethod(languageClass, getDefaultLocaleId));
+  static jmethodID const getSystemLocalesId =
+      jni::GetStaticMethodID(env, languageClass, "getSystemLocales", "()[Ljava/lang/String;");
 
-  std::string res = jni::ToNativeString(env, (jstring)localeRef.get());
-  if (res.empty())
-    res = DEFAULT_LANG;
+  jni::TScopedLocalRef resultArray(env, env->CallStaticObjectMethod(languageClass, getSystemLocalesId));
 
-  return res;
+  jobjectArray array = static_cast<jobjectArray>(resultArray.get());
+  size_t len = env->GetArrayLength(array);
+
+  std::vector<std::string> languages;
+  languages.reserve(len);
+
+  for (size_t i = 0; i < len; ++i)
+  {
+    jni::TScopedLocalRef elem(env, env->GetObjectArrayElement(array, i));
+    std::string lang = jni::ToNativeString(env, static_cast<jstring>(elem.get()));
+
+    languages.push_back(lang);
+  }
+
+  return languages;
 }
 
 namespace platform

android/sdk/src/main/java/app/organicmaps/sdk/util/Language.java

@@ -1,11 +1,16 @@
 package app.organicmaps.sdk.util;
 
 import android.content.Context;
+import android.content.res.Resources;
+import android.os.Build;
+import android.os.LocaleList;
 import android.text.TextUtils;
 import android.view.inputmethod.InputMethodManager;
 import android.view.inputmethod.InputMethodSubtype;
 import androidx.annotation.Keep;
 import androidx.annotation.NonNull;
+import java.util.ArrayList;
+import java.util.List;
 import java.util.Locale;
 
 public class Language
@@ -33,6 +38,36 @@ public class Language
     return lang;
   }
 
+  @Keep
+  @SuppressWarnings("unused")
+  @NonNull
+  public static String[] getSystemLocales()
+  {
+    List<String> result = new ArrayList<>();
+
+    // Check for Android version high enough to support Locale Preference list
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N)
+    {
+      // Gets user language preference list, on system level - app-specific changes are not applied
+      // (For that a Context object would be necessary)
+      LocaleList list = Resources.getSystem().getConfiguration().getLocales();
+      for (int i = 0; i < list.size(); i++)
+      {
+        String lang = list.get(i).toString();
+        if (lang.startsWith("in"))
+          lang = "id";
+        if (lang.startsWith("iw"))
+          lang = "he";
+        result.add(lang);
+      }
+    }
+    else
+    {
+      result.add(Locale.getDefault().toString());
+    }
+    return result.toArray(new String[0]);
+  }
+
   // After some testing on Galaxy S4, looks like this method doesn't work on all devices:
   // sometime it always returns the same value as getDefaultLocale()
   @NonNull

libs/platform/preferred_languages.cpp

@@ -24,7 +24,7 @@
 #include <cstdlib>
 #elif defined(OMIM_OS_ANDROID)
 /// Body for this function is inside android/sdk/src/main/cpp sources
-std::string GetAndroidSystemLanguage();
+std::vector<std::string> GetAndroidSystemLanguages();
 #else
 #error "Define language preferences for your platform"
 #endif
@@ -514,7 +514,9 @@ struct SystemLanguages
     }
 
 #elif defined(OMIM_OS_ANDROID)
-    m_langs.push_back(GetAndroidSystemLanguage());
+    std::vector<std::string> system_langs = GetAndroidSystemLanguages();
+    for (auto const & lang : system_langs)
+      m_langs.push_back(lang);
 #else
 #error "Define language preferences for your platform"
 #endif