code: public static void connect(Activity activity, final ConnectHandler callback) {
          HMSAgentLog.i("start connect");
          ApiClientMgr.INST.connect(new IClientConnectCallback() {
              @Override
              public void onConnect(final int rst, HuaweiApiClient client) {
                  if (callback != null) {
                      new Handler(Looper.getMainLooper()).post(new Runnable() {
                          @Override
                          public void run() {
                              callback.onConnect(rst);
                          }
                      });
                  }
              }
          }, true);
      }
docs: 连接HMS SDK， 可能拉起界面(包括升级引导等)，建议在第一个界面进行连接。 | Connecting to the HMS SDK may pull up the activity (including upgrade guard, etc.), and it is recommended that you connect in the first activity.
  此方法可以重复调用，没必要为了只调用一次做复杂处理 | This method can be called repeatedly, and there is no need to do complex processing for only one call at a time
  方法为异步调用，调用结果在主线程回调 | Method is called asynchronously, and the result is invoked in the main thread callback
  @param activity 当前界面的activity， 不能传空 | Activity of the current activity, cannot be empty
  @param callback 连接结果回调 | Connection Result Callback