Added language support on Android Viewer

Change-Id: I05a189dcee9cf4415ce59771da03c08cf0fef6c4
Signed-off-by: Mert Tumer <merttumer@outlook.com>
Reviewed-on: https://gerrit.libreoffice.org/60727
Tested-by: Jenkins
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>

android/source/res/values/arrays.xml

@@ -12,6 +12,9 @@
         <item >1</item>
         <item >2</item>
     </string-array>
+    <string-array name="SupportedLanguagesValues">
+        <item >en</item>
+    </string-array>
     <string-array name="SortModeStringValues">
         <item >0</item>
         <item >1</item>
@@ -36,6 +39,9 @@
         <item>@string/filter_presentations</item>
         <item>@string/filter_drawings</item>
     </string-array>
+    <string-array name="SupportedLanguages">
+        <item>English</item>
+    </string-array>
     <string-array name="SortModeNames">
         <item >@string/sort_az</item>
         <item >@string/sort_za</item>

android/source/res/xml/libreoffice_preferences.xml

@@ -22,6 +22,15 @@
             android:title="@string/pref_file_explorer_title"
             android:key="EXPLORER_VIEW_TYPE"
             android:summary="@string/pref_viewmode_summary" />
+
+        <ListPreference
+            android:title="Display Language"
+            android:summary="Set the default display language"
+            android:entries="@array/SupportedLanguages"
+            android:entryValues="@array/SupportedLanguagesValues"
+            android:key="DISPLAY_LANGUAGE"
+            />
+
         <CheckBoxPreference
             android:title="@string/pref_show_hidden_files"
             android:key="ENABLE_SHOW_HIDDEN_FILES"

android/source/src/java/org/libreoffice/LibreOfficeApplication.java

@@ -11,6 +11,7 @@
 package org.libreoffice;
 
 import android.app.Application;
+import android.content.Context;
 import android.os.Handler;
 
 public class LibreOfficeApplication extends Application {
@@ -24,4 +25,9 @@ public class LibreOfficeApplication extends Application {
     public static Handler getMainHandler() {
         return mainHandler;
     }
+
+    @Override
+    protected void attachBaseContext(Context base) {
+        super.attachBaseContext(LocaleHelper.onAttach(base, "en"));
+    }
 }

android/source/src/java/org/libreoffice/LocaleHelper.java

+package org.libreoffice;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.content.res.Configuration;
+import android.content.res.Resources;
+import android.os.Build;
+import android.preference.PreferenceManager;
+
+import java.util.Locale;
+
+public class LocaleHelper {
+
+    private static final String SELECTED_LANG = "org.libreoffice.selected.lang";
+
+    public static Context onAttach(Context context){
+        String lang = getPersistedData(context, Locale.getDefault().getLanguage());
+        return setLocale(context, lang);
+    }
+
+    public static Context onAttach(Context context, String defLang){
+        String lang = getPersistedData(context, defLang);
+        return setLocale(context, lang);
+    }
+
+    public static Context setLocale(Context context, String lang) {
+        persist(context, lang);
+        return updateResources(context, lang);
+    }
+
+    @SuppressWarnings("deprecation")
+    private static Context updateResources(Context context, String lang) {
+        Locale locale = new Locale(lang);
+        Locale.setDefault(locale);
+
+        Resources res = context.getResources();
+        Configuration cfg = res.getConfiguration();
+        cfg.locale = locale;
+        if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1)
+            cfg.setLayoutDirection(locale);
+
+        res.updateConfiguration(cfg, res.getDisplayMetrics());
+        return context;
+    }
+
+    private static void persist(Context context, String lang) {
+        SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(context);
+        preferences.edit().putString(SELECTED_LANG, lang);
+        preferences.edit().apply();
+    }
+
+    private static String getPersistedData(Context context, String lang) {
+        SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(context);
+        return preferences.getString(SELECTED_LANG, lang);
+    }
+}

android/source/src/java/org/libreoffice/SettingsActivity.java

@@ -48,6 +48,9 @@ public class SettingsActivity extends Activity {
         @Override
         public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
             SettingsListenerModel.getInstance().changePreferenceState(sharedPreferences, key);
+            if(key.equals("DISPLAY_LANGUAGE")){
+                getActivity().recreate();
+            }
         }
     }
 }

android/source/src/java/org/libreoffice/ui/LibreOfficeUIActivity.java

@@ -67,6 +67,7 @@ import android.widget.Toast;
 import org.libreoffice.AboutDialogFragment;
 import org.libreoffice.LOKitShell;
 import org.libreoffice.LibreOfficeMainActivity;
+import org.libreoffice.LocaleHelper;
 import org.libreoffice.R;
 import org.libreoffice.SettingsActivity;
 import org.libreoffice.SettingsListenerModel;
@@ -95,6 +96,8 @@ public class LibreOfficeUIActivity extends AppCompatActivity implements Settings
     private int viewMode;
     private int sortMode;
     private boolean showHiddenFiles;
+    private String displayLanguage;
+
     // dynamic permissions IDs
     private static final int PERMISSION_READ_EXTERNAL_STORAGE = 0;
 
@@ -115,6 +118,7 @@ public class LibreOfficeUIActivity extends AppCompatActivity implements Settings
     public static final String SORT_MODE_KEY = "SORT_MODE";
     private static final String RECENT_DOCUMENTS_KEY = "RECENT_DOCUMENTS";
     private static final String ENABLE_SHOW_HIDDEN_FILES_KEY = "ENABLE_SHOW_HIDDEN_FILES";
+    private static final String DISPLAY_LANGUAGE = "DISPLAY_LANGUAGE";
 
     public static final String NEW_FILE_PATH_KEY = "NEW_FILE_PATH_KEY";
     public static final String NEW_DOC_TYPE_KEY = "NEW_DOC_TYPE_KEY";
@@ -148,7 +152,6 @@ public class LibreOfficeUIActivity extends AppCompatActivity implements Settings
     private LinearLayout impressLayout;
     private LinearLayout calcLayout;
 
-
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -173,6 +176,11 @@ public class LibreOfficeUIActivity extends AppCompatActivity implements Settings
         fabCloseAnimation = AnimationUtils.loadAnimation(this, R.anim.fab_close);
     }
 
+    @Override
+    protected void attachBaseContext(Context newBase) {
+        super.attachBaseContext(LocaleHelper.onAttach(newBase,"en"));
+    }
+
     public void createUI() {
 
         setContentView(R.layout.activity_document_browser);
@@ -834,6 +842,7 @@ public class LibreOfficeUIActivity extends AppCompatActivity implements Settings
         viewMode = Integer.valueOf(defaultPrefs.getString(EXPLORER_VIEW_TYPE_KEY, ""+ GRID_VIEW));
         filterMode = Integer.valueOf(defaultPrefs.getString(FILTER_MODE_KEY , "-1"));
         showHiddenFiles = defaultPrefs.getBoolean(ENABLE_SHOW_HIDDEN_FILES_KEY, false);
+        displayLanguage = defaultPrefs.getString(DISPLAY_LANGUAGE, "en");
 
         Intent i = this.getIntent();
         if (i.hasExtra(CURRENT_DIRECTORY_KEY)) {
@@ -855,6 +864,8 @@ public class LibreOfficeUIActivity extends AppCompatActivity implements Settings
             viewMode = i.getIntExtra( EXPLORER_VIEW_TYPE_KEY, GRID_VIEW);
             Log.d(LOGTAG, EXPLORER_VIEW_TYPE_KEY);
         }
+
+        LocaleHelper.setLocale(this, displayLanguage);
     }
 
     @Override