Question

我正在使用angular来实现一个计数器，如下所示：

<button ng-click="order.startOperation(operation)">
   <p ng-if="counter.start"></p>
</button>

该按钮调用一个函数来启动计数器。我还有一个ng-if语句，这样如果计数器启动，用户可以看到分钟和秒运行。计数器启动后，可以使用相同的按钮停止计数器。

  function startOperation(operation) {

    var operation.lastStart = Date.now();
        operation.playing = true;

  }

  // Pause an operation timer.
  function pauseOperation(operation) {
    var operation = vm.data.operations[vm.data.operations.indexOf(operation)];

    if (!operation.start) {
      operation.start = operation.lastStart;
    }

    operation.end = Date.now();

    // Sumarize the transcurred seconds.
    operation.partialTime = operation.partialTime || 0;
    operation.partialTime += Math.ceil((operation.end - operation.lastStart) / 1000);
    dataService.update();
  }

Answer 1

你需要$elapsedTime变量每隔一秒更新一次：

<button ng-click="order.startOperation(operation)">
    <p ng-if="counter.start">{{$elapsedTime}}</p>
</button>

要更新其值，请使用$timeout服务：

var updateElapsedTime = function () {
    $scope.elapsedTime = Date.now() - operation.lastStart;
    if (operation.playing) {
        // keep updating
        $timeout(updateElapsedTime, 1000);
    }
}

updateElapsedTime();

如何启动计数器？

1 个答案: