Settings模块

需求：对Settings主界面进行管控，输入某串暗码，Settings中指定项隐藏（如Wifi、Bluetooth）；输入另一串暗码，Settings中隐藏项恢复显示。


/packages/app/Settings/com/android/settings/SettingsActivity.java
在SettingsActivity中会有部分item的控制：

doUpdateTilesList(){
        PackageManager pm = getPackageManager();
        final UserManager um = UserManager.get(this);
        final boolean isAdmin = um.isAdminUser();

        String packageName = getPackageName();
        setTileEnabled(new ComponentName(packageName, WifiSettingsActivity.class.getName()),
                pm.hasSystemFeature(PackageManager.FEATURE_WIFI), isAdmin, pm);

        setTileEnabled(new ComponentName(packageName,
                Settings.BluetoothSettingsActivity.class.getName()),
                pm.hasSystemFeature(PackageManager.FEATURE_BLUETOOTH), isAdmin, pm);

        setTileEnabled(new ComponentName(packageName,
                Settings.DataUsageSummaryActivity.class.getName()),
                Utils.isBandwidthControlEnabled(), isAdmin, pm);

        setTileEnabled(new ComponentName(packageName,
                Settings.SimSettingsActivity.class.getName()),
                Utils.showSimCardTile(this), isAdmin, pm);
        //location
        setTileEnabled(new ComponentName(packageName,
                Settings.LocationSettingsActivity.class.getName()),
                false, isAdmin, pm);

        setTileEnabled(new ComponentName(packageName,
                Settings.PowerUsageSummaryActivity.class.getName()),
                mBatteryPresent, isAdmin, pm);

        setTileEnabled(new ComponentName(packageName,
                Settings.UserSettingsActivity.class.getName()),
                UserHandle.MU_ENABLED && UserManager.supportsMultipleUsers()
                && !Utils.isMonkeyRunning(), isAdmin, pm);

        setTileEnabled(new ComponentName(packageName,
                        Settings.WirelessSettingsActivity.class.getName()),
                !UserManager.isDeviceInDemoMode(this), isAdmin, pm);

        setTileEnabled(new ComponentName(packageName,
                        Settings.DateTimeSettingsActivity.class.getName()),
                !UserManager.isDeviceInDemoMode(this), isAdmin, pm);
        NfcAdapter adapter = NfcAdapter.getDefaultAdapter(this);
        setTileEnabled(new ComponentName(packageName,
                        Settings.PaymentSettingsActivity.class.getName()),
                pm.hasSystemFeature(PackageManager.FEATURE_NFC)
                        && pm.hasSystemFeature(PackageManager.FEATURE_NFC_HOST_CARD_EMULATION)
                        && adapter != null && adapter.isEnabled(), isAdmin, pm);

        setTileEnabled(new ComponentName(packageName,
                Settings.PrintSettingsActivity.class.getName()),
                pm.hasSystemFeature(PackageManager.FEATURE_PRINTING), isAdmin, pm);

        final boolean showDev = mDevelopmentPreferences.getBoolean(
                    DevelopmentSettings.PREF_SHOW, android.os.Build.TYPE.equals("eng"))
                && !um.hasUserRestriction(UserManager.DISALLOW_DEBUGGING_FEATURES);
        setTileEnabled(new ComponentName(packageName,
                        Settings.DevelopmentSettingsActivity.class.getName()),
                showDev, isAdmin, pm);
       if(!SystemProperties.get("ro.build.characteristics","null").equals("tablet")) {
           setTileEnabled(new ComponentName(packageName,
                           Settings.ScreenshotSettingsActivity.class.getName()),
                   false, isAdmin, pm);
       }
}

    可在此处自行增加缺失的settings项来控制显示/隐藏。也可查找上游。

    其中显示则为pm.hasSystemFeature(PackageManager.FEATURE_PRINTING)如此类型，隐藏则为false。但是通过对代码解读发现，此处只可控制部分item的显示与隐藏，无法达到对所有item的管控。所以此处不是正确修改点。
    继续追踪Settings的显示流程，发现其中所有的item都是继承SettingsActivity，并通过AndroidManifest.xml中的配置项来分配指定fragment。这是有读取

<activity android:name="Settings"
                android:taskAffinity="com.android.settings"
                android:label="@string/settings_label_launcher"
                android:launchMode="singleTask">
            <intent-filter android:priority="1">
                <action android:name="android.settings.SETTINGS" />
                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
            <meta-data android:name="com.android.settings.PRIMARY_PROFILE_CONTROLLED"
                android:value="true" />
        </activity>

类似这样的属性值来完成此项操作的。具体的流程追踪此处不做详。

在framework中的TileUtils.java类中会对Category进行获取、创建等操作，这是绘制到Settings中的主要属性。

    public static List<DashboardCategory>getCategories(Context context,
            HashMap<Pair<String, String>, Tile> cache) {
        final long startTime = System.currentTimeMillis();
        boolean setup = Global.getInt(context.getContentResolver(), Global.DEVICE_PROVISIONED, 0)
                != 0;
        ArrayList<Tile> tiles = new ArrayList<>();
        UserManager userManager = UserManager.get(context);
        for (UserHandle user : userManager.getUserProfiles()) {
            // TODO: Needs much optimization, too many PM queries going on here.
            if (user.getIdentifier() == ActivityManager.getCurrentUser()) {
                // Only add Settings for this user.
                getTilesForAction(context, user, SETTINGS_ACTION, cache, null, tiles, true);
                getTilesForAction(context, user, OPERATOR_SETTINGS, cache,
                        OPERATOR_DEFAULT_CATEGORY, tiles, false);
                getTilesForAction(context, user, MANUFACTURER_SETTINGS, cache,
                        MANUFACTURER_DEFAULT_CATEGORY, tiles, false);
            }
            if (setup) {
                getTilesForAction(context, user, EXTRA_SETTINGS_ACTION, cache, null, tiles, false);
            }
        }
        boolean isSupportBluetooth = "true".equals(SystemProperties.get("ro.rk.bt_enable"));
        HashMap<String, DashboardCategory> categoryMap = new HashMap<>();
        for (Tile tile : tiles) {
            DashboardCategory category = categoryMap.get(tile.category);
            if (category == null) {
                category = createCategory(context, tile.category);
                if (category == null) {
                    Log.w(LOG_TAG, "Couldn't find category " + tile.category);
                    continue;
                }
                categoryMap.put(category.key, category);
            }
            Intent tileIntent = tile.intent;
            if(!isSupportBluetooth && tileIntent != null && tileIntent.toString().contains("com.android.settings/.Settings$BluetoothSettingsActivity"))
                continue;
            category.addTile(tile);
        }
        ArrayList<DashboardCategory> categories = new ArrayList<>(categoryMap.values());
        for (DashboardCategory category : categories) {
            Collections.sort(category.tiles, TILE_COMPARATOR);
        }
        Collections.sort(categories, CATEGORY_COMPARATOR);
        if (DEBUG_TIMING) Log.d(LOG_TAG, "getCategories took "
                + (System.currentTimeMillis() - startTime) + " ms");
        return categories;
    }

可以通过getCategories()中的tile来获取到Component信息： tile.intent.getComponent()
通过对需要屏蔽的Component进行筛选，不走这个流程就可以完成对相关item的屏蔽操作。

暗码可以通过计算器中的onEquals或拨号器来获取到输入的指定字符串，通过SystemProperties可以进行控制，对Settings的隐藏和显示做管控。