当我锁定手机时，计时器停止计时

Question

我在JavaScript中有一个计时器，当我锁定手机时，计时器仍会计数几分钟，此后便停止。如果我解锁手机，计时器将开始计时。当手机屏幕关闭时，计时器是否还能计数？

    <script>
    var seconds=0;
    function pad(val) { return val > 9 ? val : "0" + val; } 
     if(sessionStorage.getItem("self.totalSeconds") != null ){

            $("#min").text(pad(Math.floor(sessionStorage.getItem("self.totalSeconds") / 60 % 60)));
      $("#sec").text(pad(parseInt(sessionStorage.getItem("self.totalSeconds") % 60)));
            seconds=parseInt(sessionStorage.getItem("self.totalSeconds"));
          }else{
            $("#min").text("00");
            $("#sec").text("00");
          }
    var Clock = {
      totalSeconds: seconds,
      start: function () {
        var self = this;
        this.interval = setInterval(function () {

          if(sessionStorage.getItem("self.totalSeconds") == null ){
            self.totalSeconds += 1;
          }else{
            self.totalSeconds=parseInt(sessionStorage.getItem("self.totalSeconds"));
            self.totalSeconds += 1;
          }
          sessionStorage.setItem("self.totalSeconds", self.totalSeconds);

          $("#min").text(pad(Math.floor(sessionStorage.getItem("self.totalSeconds") / 60 % 60)));
          $("#sec").text(pad(parseInt(sessionStorage.getItem("self.totalSeconds") % 60)));

        }, 1000);

      },

      pause: function () {
        clearInterval(this.interval);
        delete this.interval;
      },
    };

    Clock.start();
    $('#pauseButton').click(function () {
     $("#errorMessage").text("");
     $("#errorMessage").hide();
     var totalSecondstobeexported = Clock.totalSeconds;
});
  </script>