How to start activity Language and input

            Resources res = getResources();
            // Change locale settings in the app.
            DisplayMetrics dm = res.getDisplayMetrics();
            android.content.res.Configuration conf = res.getConfiguration();
            conf.locale = new Locale("put the value that u get from SharedPreferences);
            res.updateConfiguration(conf, dm);

 protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    //some code here
    if (last_local.equals("fa") && current_local.equals("en"))
        setLocale("fa");
    //some code here
}

 public void setLocale(String languageToLoad){
    Locale locale = new Locale(languageToLoad);
    Locale.setDefault(locale);
    Configuration config = new Configuration();
    config.locale = locale;
    getResources().updateConfiguration(config, getBaseContext().getResources().getDisplayMetrics());
    SharedPreferences Settings=getSharedPreferences("Last Setting",1);
    Settings.edit().putString("Locale Status", languageToLoad).commit();
    Intent intent = new Intent(getApplicationContext(), MainActivity.class);
    intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
    startActivity(intent);
}

android:targetClass

android:targetPackage 

ComponentName(String package, String class)

<intent android:action="android.intent.action.MAIN"
android:targetPackage="com.android.settings"
android:targetClass="com.android.settings.LanguageSettings" />

View view = inflater.inflate(R.layout.activity_initialize_test, null);
final EditText editText = (EditText) view.findViewById(R.id.filename);

builder.setPositiveButton(R.string.start_test, new DialogInterface.OnClickListener() {            
    @Override
    public void onClick(DialogInterface dialog, int id) {
        String filename = editText.getText().toString();
        Context context = getContext();
        Intent intent = new Intent(context, InitializeTest.class);
        intent.putExtra(FILENAME, filename);
        context.startActivity(intent);
    }
});