修改文件1：:frameworks/base/packages/SettingsProvider/res/values/defaults.xml

<!-- set default input method@suntb -->
    <string name="def_input_method" translatable="false">com.android.inputmethod.latin/.LatinIME</string>
	<string name="def_enabled_input_methods" translatable="false">com.android.inputmethod.latin/.LatinIME</string>

修改文件2：frameworks/base/packages/SettingsProvider/src/com/android/providers/settings/DatabaseHelper.java#loadDefaultHapticSettings

 private void loadDefaultHapticSettings(SQLiteStatement stmt) {
        loadBooleanSetting(stmt, Settings.System.HAPTIC_FEEDBACK_ENABLED,
                R.bool.def_haptic_feedback);
    }

    private void loadSecureSettings(SQLiteDatabase db) {
        SQLiteStatement stmt = null;
        try {
            stmt = db.compileStatement("INSERT OR IGNORE INTO secure(name,value)"
                    + " VALUES(?,?);");

            // Don't do this.  The SystemServer will initialize ADB_ENABLED from a
            // persistent system property instead.
            //loadSetting(stmt, Settings.Secure.ADB_ENABLED, 0);

            // Allow mock locations default, based on build
            loadSetting(stmt, Settings.Secure.ALLOW_MOCK_LOCATION,
                    "1".equals(SystemProperties.get("ro.allow.mock.location")) ? 1 : 0);

            loadSecure35Settings(stmt);

            loadBooleanSetting(stmt, Settings.Secure.MOUNT_PLAY_NOTIFICATION_SND,
                    R.bool.def_mount_play_notification_snd);

            loadBooleanSetting(stmt, Settings.Secure.MOUNT_UMS_AUTOSTART,
                    R.bool.def_mount_ums_autostart);

            loadBooleanSetting(stmt, Settings.Secure.MOUNT_UMS_PROMPT,
                    R.bool.def_mount_ums_prompt);

            loadBooleanSetting(stmt, Settings.Secure.MOUNT_UMS_NOTIFY_ENABLED,
                    R.bool.def_mount_ums_notify_enabled);

            loadIntegerSetting(stmt, Settings.Secure.LONG_PRESS_TIMEOUT,
                    R.integer.def_long_press_timeout_millis);

            loadBooleanSetting(stmt, Settings.Secure.TOUCH_EXPLORATION_ENABLED,
                    R.bool.def_touch_exploration_enabled);

            loadBooleanSetting(stmt, Settings.Secure.ACCESSIBILITY_SPEAK_PASSWORD,
                    R.bool.def_accessibility_speak_password);

            if (SystemProperties.getBoolean("ro.lockscreen.disable.default", false) == true) {
                loadSetting(stmt, Settings.System.LOCKSCREEN_DISABLED, "1");
            } else {
                loadBooleanSetting(stmt, Settings.System.LOCKSCREEN_DISABLED,
                        R.bool.def_lockscreen_disabled);
            }

            loadBooleanSetting(stmt, Settings.Secure.SCREENSAVER_ENABLED,
                    com.android.internal.R.bool.config_dreamsEnabledByDefault);
            loadBooleanSetting(stmt, Settings.Secure.SCREENSAVER_ACTIVATE_ON_DOCK,
                    com.android.internal.R.bool.config_dreamsActivatedOnDockByDefault);
            loadBooleanSetting(stmt, Settings.Secure.SCREENSAVER_ACTIVATE_ON_SLEEP,
                    com.android.internal.R.bool.config_dreamsActivatedOnSleepByDefault);
            loadStringSetting(stmt, Settings.Secure.SCREENSAVER_DEFAULT_COMPONENT,
                    com.android.internal.R.string.config_dreamsDefaultComponent);

            loadBooleanSetting(stmt, Settings.Secure.ACCESSIBILITY_DISPLAY_MAGNIFICATION_ENABLED,
                    R.bool.def_accessibility_display_magnification_enabled);

            loadFractionSetting(stmt, Settings.Secure.ACCESSIBILITY_DISPLAY_MAGNIFICATION_SCALE,
                    R.fraction.def_accessibility_display_magnification_scale, 1);

            loadBooleanSetting(stmt, Settings.Secure.USER_SETUP_COMPLETE,
                    R.bool.def_user_setup_complete);

            loadStringSetting(stmt, Settings.Secure.IMMERSIVE_MODE_CONFIRMATIONS,
                        R.string.def_immersive_mode_confirmations);

            loadBooleanSetting(stmt, Settings.Secure.INSTALL_NON_MARKET_APPS,
                    R.bool.def_install_non_market_apps);

            loadBooleanSetting(stmt, Settings.Secure.WAKE_GESTURE_ENABLED,
                    R.bool.def_wake_gesture_enabled);

            loadIntegerSetting(stmt, Secure.LOCK_SCREEN_SHOW_NOTIFICATIONS,
                    R.integer.def_lock_screen_show_notifications);

            loadBooleanSetting(stmt, Secure.LOCK_SCREEN_ALLOW_PRIVATE_NOTIFICATIONS,
                    R.bool.def_lock_screen_allow_private_notifications);

            loadIntegerSetting(stmt, Settings.Secure.SLEEP_TIMEOUT,
                    R.integer.def_sleep_timeout);
			// set default input method @suntb
			loadStringSetting(stmt, Settings.Secure.DEFAULT_INPUT_METHOD,
                    R.string.def_input_method);
			loadStringSetting(stmt, Settings.Secure.ENABLED_INPUT_METHODS,
					R.string.def_enabled_input_methods);

            /*
             * IMPORTANT: Do not add any more upgrade steps here as the global,
             * secure, and system settings are no longer stored in a database
             * but are kept in memory and persisted to XML.
             *
             * See: SettingsProvider.UpgradeController#onUpgradeLocked
             */
        } finally {
            if (stmt != null) stmt.close();
        }
    }