默认打开蓝牙开关 蓝牙是不可以被其他设备发现的

只能在蓝牙界面才可以被发现

如果想打开开关就被发现

需修改代码

btservice/AdapterProperties.java

 void onBluetoothReady() {
        debugLog("onBluetoothReady, state=" + BluetoothAdapter.nameForState(getState())
                + ", ScanMode=" + mScanMode);

        synchronized (mObject) {
            // Reset adapter and profile connection states
            setConnectionState(BluetoothAdapter.STATE_DISCONNECTED);
            mProfileConnectionState.clear();
            mProfilesConnected = 0;
            mProfilesConnecting = 0;
            mProfilesDisconnecting = 0;
            // adapterPropertyChangedCallback has already been received.  Set the scan mode.
            //setScanMode(AbstractionLayer.BT_SCAN_MODE_CONNECTABLE);

            //可以连接 不能被发现
            setScanMode(AbstractionLayer.BT_SCAN_MODE_CONNECTABLE_DISCOVERABLE);

            //可以连接 也可以被发现
            
            // This keeps NV up-to date on first-boot after flash.
            setDiscoverableTimeout(mDiscoverableTimeout);
        }
    }