广告 BLE 设备

你可以使用蓝牙 LE 广告将数据包广播到所有附近的设备，而无需先建立连接。请记住，严格限制 31 个字节的广告数据。宣传你的设备也是让其他用户与你联系的第一步。

由于并非所有设备都支持蓝牙 LE 广告，因此第一步是检查你的设备是否具备支持它的所有必要要求。之后，你可以初始化 BluetoothLeAdvertiser 对象，并使用它，你可以开始广告操作：

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP && bluetoothAdapter.isMultipleAdvertisementSupported())
        {
            BluetoothLeAdvertiser advertiser = bluetoothAdapter.getBluetoothLeAdvertiser();

            AdvertiseData.Builder dataBuilder = new AdvertiseData.Builder();
           //Define a service UUID according to your needs                
           dataBuilder.addServiceUuid(SERVICE_UUID);
            dataBuilder.setIncludeDeviceName(true);

             AdvertiseSettings.Builder settingsBuilder = new AdvertiseSettings.Builder();
             settingsBuilder.setAdvertiseMode(AdvertiseSettings.ADVERTISE_MODE_LOW_POWER);
             settingsBuilder.setTimeout(0);

             //Use the connectable flag if you intend on opening a Gatt Server
             //to allow remote connections to your device.
             settingsBuilder.setConnectable(true);

            AdvertiseCallback advertiseCallback=new AdvertiseCallback() {
            @Override
            public void onStartSuccess(AdvertiseSettings settingsInEffect) {
                super.onStartSuccess(settingsInEffect);
                Log.i(TAG, "onStartSuccess: ");
            }

            @Override
            public void onStartFailure(int errorCode) {
                super.onStartFailure(errorCode);
                Log.e(TAG, "onStartFailure: "+errorCode );
            }
          };
advertising.startAdvertising(settingsBuilder.build(),dataBuilder.build(),advertiseCallback);
        }