Add in-app language selection support.

src/org/thoughtcrime/securesms/ApplicationPreferencesActivity.java

@@ -25,27 +25,22 @@ import android.net.Uri;
 import android.os.Bundle;
 import android.preference.EditTextPreference;
 import android.preference.Preference;
-import android.preference.PreferenceScreen;
 import android.preference.PreferenceManager;
+import android.preference.PreferenceScreen;
 import android.provider.ContactsContract;
 import android.util.Log;
 import android.widget.Toast;
 
+import com.actionbarsherlock.view.MenuItem;
 import org.thoughtcrime.securesms.contacts.ContactAccessor;
 import org.thoughtcrime.securesms.contacts.ContactIdentityManager;
-import org.thoughtcrime.securesms.crypto.IdentityKey;
 import org.thoughtcrime.securesms.crypto.IdentityKeyUtil;
 import org.thoughtcrime.securesms.crypto.MasterSecret;
 import org.thoughtcrime.securesms.crypto.MasterSecretUtil;
-import org.thoughtcrime.securesms.util.Dialogs;
+import org.thoughtcrime.securesms.util.DynamicLanguage;
 import org.thoughtcrime.securesms.util.DynamicTheme;
 import org.thoughtcrime.securesms.util.MemoryCleaner;
 import org.thoughtcrime.securesms.util.Trimmer;
-import org.thoughtcrime.securesms.util.Util;
-
-import com.actionbarsherlock.view.MenuItem;
-
-import java.util.List;
 
 /**
  * The Activity for application preference display and management.
@@ -72,6 +67,7 @@ public class ApplicationPreferencesActivity extends PassphraseRequiredSherlockPr
   public static final String PASSPHRASE_TIMEOUT_PREF          = "pref_timeout_passphrase";
   public static final String AUTO_KEY_EXCHANGE_PREF           = "pref_auto_complete_key_exchange";
   public static final String THEME_PREF                       = "pref_theme";
+  public static final String LANGUAGE_PREF                    = "pref_language";
   public static final String ENTER_SENDS_PREF                 = "pref_enter_sends";
   public static final String ENTER_PRESENT_PREF               = "pref_enter_key";
 
@@ -98,11 +94,13 @@ public class ApplicationPreferencesActivity extends PassphraseRequiredSherlockPr
   public static final String REGISTERED_GCM_PREF  = "pref_gcm_registered";
   public static final String GCM_PASSWORD_PREF    = "pref_gcm_password";
 
-  private final DynamicTheme dynamicTheme = new DynamicTheme();
+  private final DynamicTheme    dynamicTheme    = new DynamicTheme();
+  private final DynamicLanguage dynamicLanguage = new DynamicLanguage();
 
   @Override
   protected void onCreate(Bundle icicle) {
     dynamicTheme.onCreate(this);
+    dynamicLanguage.onCreate(this);
     super.onCreate(icicle);
 
     this.getSupportActionBar().setDisplayHomeAsUpEnabled(true);
@@ -134,6 +132,7 @@ public class ApplicationPreferencesActivity extends PassphraseRequiredSherlockPr
   public void onResume() {
     super.onResume();
     dynamicTheme.onResume(this);
+    dynamicLanguage.onResume(this);
   }
 
   @Override
@@ -233,6 +232,8 @@ public class ApplicationPreferencesActivity extends PassphraseRequiredSherlockPr
   public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
     if (key.equals(THEME_PREF)) {
       dynamicTheme.onResume(this);
+    } else if (key.equals(LANGUAGE_PREF)) {
+      dynamicLanguage.onResume(this);
     }
   }
 

src/org/thoughtcrime/securesms/ConversationActivity.java

@@ -80,6 +80,7 @@ import org.thoughtcrime.securesms.sms.OutgoingEncryptedMessage;
 import org.thoughtcrime.securesms.sms.OutgoingTextMessage;
 import org.thoughtcrime.securesms.util.BitmapDecodingException;
 import org.thoughtcrime.securesms.util.CharacterCalculator;
+import org.thoughtcrime.securesms.util.DynamicLanguage;
 import org.thoughtcrime.securesms.util.DynamicTheme;
 import org.thoughtcrime.securesms.util.EncryptedCharacterCalculator;
 import org.thoughtcrime.securesms.util.InvalidMessageException;
@@ -138,10 +139,12 @@ public class ConversationActivity extends PassphraseRequiredSherlockFragmentActi
 
   private CharacterCalculator characterCalculator = new CharacterCalculator();
   private DynamicTheme        dynamicTheme        = new DynamicTheme();
+  private DynamicLanguage     dynamicLanguage     = new DynamicLanguage();
 
   @Override
   protected void onCreate(Bundle state) {
     dynamicTheme.onCreate(this);
+    dynamicLanguage.onCreate(this);
     super.onCreate(state);
 
     setContentView(R.layout.conversation_activity);
@@ -165,6 +168,7 @@ public class ConversationActivity extends PassphraseRequiredSherlockFragmentActi
   protected void onResume() {
     super.onResume();
     dynamicTheme.onResume(this);
+    dynamicLanguage.onResume(this);
 
     initializeSecurity();
     initializeTitleBar();

src/org/thoughtcrime/securesms/ConversationListActivity.java

@@ -28,6 +28,7 @@ import org.thoughtcrime.securesms.recipients.RecipientFactory;
 import org.thoughtcrime.securesms.recipients.Recipients;
 import org.thoughtcrime.securesms.service.KeyCachingService;
 import org.thoughtcrime.securesms.service.SendReceiveService;
+import org.thoughtcrime.securesms.util.DynamicLanguage;
 import org.thoughtcrime.securesms.util.DynamicTheme;
 import org.thoughtcrime.securesms.util.MemoryCleaner;
 
@@ -39,7 +40,8 @@ public class ConversationListActivity extends PassphraseRequiredSherlockFragment
     implements ConversationListFragment.ConversationSelectedListener,
                ListView.OnItemClickListener
   {
-  private final DynamicTheme dynamicTheme = new DynamicTheme();
+  private final DynamicTheme    dynamicTheme    = new DynamicTheme   ();
+  private final DynamicLanguage dynamicLanguage = new DynamicLanguage();
 
   private ConversationListFragment fragment;
   private MasterSecret masterSecret;
@@ -49,6 +51,7 @@ public class ConversationListActivity extends PassphraseRequiredSherlockFragment
   @Override
   public void onCreate(Bundle icicle) {
     dynamicTheme.onCreate(this);
+    dynamicLanguage.onCreate(this);
     super.onCreate(icicle);
 
     setContentView(R.layout.conversation_list_activity);
@@ -64,6 +67,7 @@ public class ConversationListActivity extends PassphraseRequiredSherlockFragment
   public void onResume() {
     super.onResume();
     dynamicTheme.onResume(this);
+    dynamicLanguage.onResume(this);
   }
 
   @Override

src/org/thoughtcrime/securesms/util/DynamicLanguage.java

@@ -0,0 +1,70 @@
+package org.thoughtcrime.securesms.util;
+
+import android.app.Activity;
+import android.content.Intent;
+import android.content.res.Configuration;
+import android.os.Build;
+import android.preference.PreferenceManager;
+import android.util.Log;
+
+import org.thoughtcrime.securesms.ApplicationPreferencesActivity;
+
+import java.util.Locale;
+
+public class DynamicLanguage {
+
+  private static final String DEFAULT = "zz";
+
+  private Locale currentLocale;
+
+  public void onCreate(Activity activity) {
+    currentLocale = getSelectedLocale(activity);
+    setActivityLocale(activity, currentLocale);
+  }
+
+  public void onResume(Activity activity) {
+    if (!currentLocale.getLanguage().equalsIgnoreCase(getSelectedLocale(activity).getLanguage())) {
+      Intent intent = activity.getIntent();
+      intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
+
+      activity.startActivity(intent);
+      if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ECLAIR) {
+        OverridePendingTransition.invoke(activity);
+      }
+
+      activity.finish();
+      if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ECLAIR) {
+        OverridePendingTransition.invoke(activity);
+      }
+    }
+  }
+
+  private static void setActivityLocale(Activity activity, Locale selectedLocale) {
+    Configuration configuration = activity.getResources().getConfiguration();
+
+    if (!configuration.locale.getLanguage().equalsIgnoreCase(selectedLocale.getLanguage())) {
+      configuration.locale = selectedLocale;
+      activity.getResources().updateConfiguration(configuration,
+                                                  activity.getResources().getDisplayMetrics());
+    }
+  }
+
+  private static Locale getActivityLocale(Activity activity) {
+    return activity.getResources().getConfiguration().locale;
+  }
+
+  private static Locale getSelectedLocale(Activity activity) {
+    String language =  PreferenceManager.getDefaultSharedPreferences(activity)
+                                        .getString(ApplicationPreferencesActivity.LANGUAGE_PREF, DEFAULT);
+
+    if (language.equals(DEFAULT)) return Locale.getDefault();
+    else                          return new Locale(language);
+  }
+
+  private static final class OverridePendingTransition {
+    static void invoke(Activity activity) {
+      activity.overridePendingTransition(0, 0);
+    }
+  }
+
+}