android源码中修改wifi热点默认始终开启

在项目\frameworks\base\wifi\java\android\net\wifi\WifiStateMachine.java里面，有如下的代码，是设置wifi热点保持状态的：如下：　

 private class HotspotAutoDisableObserver extends ContentObserver {
        public HotspotAutoDisableObserver(Handler handler) {
            super(handler);
            mContext.getContentResolver().registerContentObserver(Settings.System.getUriFor(
                Settings.System.WIFI_HOTSPOT_AUTO_DISABLE), false, this);
        }

        @Override
        public void onChange(boolean selfChange) {
            super.onChange(selfChange);
            mDuration = Settings.System.getInt(mContext.getContentResolver(), Settings.System.WIFI_HOTSPOT_AUTO_DISABLE,
                    Settings.System.WIFI_HOTSPOT_AUTO_DISABLE_FOR_FIVE_MINS);
            if (mDuration != Settings.System.WIFI_HOTSPOT_AUTO_DISABLE_OFF && mPluggedType == 0) {
                if (mClientNum == 0 && WifiStateMachine.this.getCurrentState() == mTetheredState) {
                    mAlarmManager.cancel(mIntentStopHotspot);
                    Xlog.d(TAG, "Set alarm for setting changed, mDuration:" + mDuration);
                    mAlarmManager.set(AlarmManager.RTC_WAKEUP,
                        System.currentTimeMillis() + mDuration * HOTSPOT_DISABLE_MS, mIntentStopHotspot);
                }
            } else {
                mAlarmManager.cancel(mIntentStopHotspot);
            }
        }
    }

修改默认值为始终：

mDuration = Settings.System.getInt(mContext.getContentResolver(), Settings.System.WIFI_HOTSPOT_AUTO_DISABLE,
                    Settings.System.WIFI_HOTSPOT_AUTO_DISABLE_OFF);

最关键的部分是修改初始化：

    private void initializeExtra() {
        PowerManager powerManager = (PowerManager)mContext.getSystemService(Context.POWER_SERVICE);
        mDhcpWakeLock = powerManager.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "DHCP_WAKELOCK");
        mDhcpWakeLock.setReferenceCounted(false);

        mHotspotNative = new WifiNative("ap0");
        mHotspotMonitor = new WifiMonitor(this, mHotspotNative);

        HandlerThread wifiThread = new HandlerThread("WifiSMForObserver");
        wifiThread.start();

        mHotspotAutoDisableObserver = new HotspotAutoDisableObserver(new Handler(wifiThread.getLooper()));
        Intent stopHotspotIntent = new Intent(ACTION_STOP_HOTSPOT);
        mIntentStopHotspot = PendingIntent.getBroadcast(mContext, STOP_HOTSPOT_REQUEST, stopHotspotIntent, 0);
        //mDuration = Settings.System.getInt(mContext.getContentResolver(), Settings.System.WIFI_HOTSPOT_AUTO_DISABLE,
        //            Settings.System.WIFI_HOTSPOT_AUTO_DISABLE_FOR_FIVE_MINS);
        mDuration = Settings.System.getInt(mContext.getContentResolver(), Settings.System.WIFI_HOTSPOT_AUTO_DISABLE,
                    Settings.System.WIFI_HOTSPOT_AUTO_DISABLE_OFF);//---------修改为默认常开

        // M: For stop scan after screen off in disconnected state feature @{
        Intent stopScanIntent = new Intent(ACTION_STOP_SCAN, null);
        mStopScanIntent = PendingIntent.getBroadcast(mContext, STOPSCAN_REQUEST, stopScanIntent, 0);

        IntentFilter intentFilter = new IntentFilter();
        intentFilter.addAction("com.mtk.beamplus.activated");
        intentFilter.addAction("com.mtk.beamplus.deactivated");
        intentFilter.addAction(ACTION_STOP_HOTSPOT);
        intentFilter.addAction(IWifiFwkExt.AUTOCONNECT_SETTINGS_CHANGE);
        intentFilter.addAction(DisplayManager.ACTION_WIFI_DISPLAY_STATUS_CHANGED);
        intentFilter.addAction(TelephonyIntents.ACTION_SIM_STATE_CHANGED);
        intentFilter.addAction(Intent.ACTION_DUAL_SIM_MODE_CHANGED);
        intentFilter.addAction(ACTION_STOP_SCAN);

        final boolean isHotspotAlwaysOnWhilePlugged = mContext.getResources().getBoolean(
                com.mediatek.internal.R.bool.is_mobile_hotspot_always_on_while_plugged);
        Xlog.d(TAG, "isHotspotAlwaysOnWhilePlugged:" + isHotspotAlwaysOnWhilePlugged);
        if (isHotspotAlwaysOnWhilePlugged) {
            intentFilter.addAction(Intent.ACTION_BATTERY_CHANGED);
        }

        BroadcastReceiver receiver = new BroadcastReceiver() {
            @Override
            public void onReceive(Context context, Intent intent) {
                String action = intent.getAction();
                Xlog.d(TAG, "onReceive, action:" + action);
                if (action.equals("com.mtk.beamplus.activated")) {
                    mBeamPlusStarted.set(true);
                    sendMessage(M_CMD_UPDATE_BGSCAN);
                } else if (action.equals("com.mtk.beamplus.deactivated")) {
                    mBeamPlusStarted.set(false);
                    sendMessage(M_CMD_UPDATE_BGSCAN);
                } else if (action.equals(ACTION_STOP_HOTSPOT)) {
                    mWifiManager.setWifiApEnabled(null, false);
                    int wifiSavedState = 0;
                    try {
                        wifiSavedState = Settings.Global.getInt(mContext.getContentResolver(),
                            Settings.Global.WIFI_SAVED_STATE);
                    } catch (Settings.SettingNotFoundException e) {
                        Xlog.e(TAG, "SettingNotFoundException:" + e);
                    }
                    Xlog.d(TAG, "Received stop hotspot intent, wifiSavedState:" + wifiSavedState);
                    if (wifiSavedState == 1) {
                        mWifiManager.setWifiEnabled(true);
                        Settings.Global.putInt(mContext.getContentResolver(), Settings.Global.WIFI_SAVED_STATE, 0);
                    }
                } else if (action.equals(IWifiFwkExt.AUTOCONNECT_SETTINGS_CHANGE)) {
                    sendMessage(M_CMD_UPDATE_SETTINGS);
                } else if (action.equals(DisplayManager.ACTION_WIFI_DISPLAY_STATUS_CHANGED)) {
                    WifiDisplayStatus status = (WifiDisplayStatus)intent.getParcelableExtra(
                        DisplayManager.EXTRA_WIFI_DISPLAY_STATUS);
                    Xlog.d(TAG, "Received ACTION_WIFI_DISPLAY_STATUS_CHANGED.");
                    setWfdConnected(status);
                    sendMessage(M_CMD_UPDATE_BGSCAN);
                } else if (action.equals(Intent.ACTION_BATTERY_CHANGED)) {
                    if (isHotspotAlwaysOnWhilePlugged) {
                        int pluggedType = intent.getIntExtra("plugged", 0);
                        Xlog.d(TAG, "ACTION_BATTERY_CHANGED pluggedType:" + pluggedType + ", mPluggedType:" + mPluggedType);
                        if (mPluggedType != pluggedType) {
                            mPluggedType = pluggedType;
                            if (mDuration != Settings.System.WIFI_HOTSPOT_AUTO_DISABLE_OFF && mPluggedType == 0) {
                                if (mClientNum == 0 && WifiStateMachine.this.getCurrentState() == mTetheredState) {
                                    mAlarmManager.cancel(mIntentStopHotspot);
                                    Xlog.d(TAG, "Set alarm for ACTION_BATTERY_CHANGED changed, mDuration:" + mDuration);
                                    mAlarmManager.set(AlarmManager.RTC_WAKEUP,
                                        System.currentTimeMillis() + mDuration * HOTSPOT_DISABLE_MS, mIntentStopHotspot);
                                }
                            } else {
                                mAlarmManager.cancel(mIntentStopHotspot);
                            }
                        }
                    }
                } else if (action.equals(TelephonyIntents.ACTION_SIM_STATE_CHANGED)) {
                    String iccState = intent.getStringExtra(IccCardConstants.INTENT_KEY_ICC_STATE);
                    Xlog.d(TAG, "iccState:" + iccState);
                    if (!iccState.equals(IccCardConstants.INTENT_VALUE_ICC_LOADED)) {
                        return;
                    }
                    sendMessage(M_CMD_UPDATE_COUNTRY_CODE);
                } else if (action.equals(Intent.ACTION_DUAL_SIM_MODE_CHANGED)) {
                    sendMessage(M_CMD_UPDATE_COUNTRY_CODE);
                } else if (action.equals(ACTION_STOP_SCAN)) {
                    sendMessage(M_CMD_SLEEP_POLICY_STOP_SCAN);
                }
            }
        };
        mContext.registerReceiver(receiver, intentFilter);

        mPppoeInfo = new PPPOEInfo();
        mPppoeLinkProperties = new LinkProperties();
    }

　　

另外，System.xxxx的常量定义在源码中的路径：项目\frameworks\base\core\java\android\provider\Settings.java