android - 为什么使用WorkManager的OneTimeWorkRequest的setInitialDelay()函数，改变设备时间时延迟不生效

Question

I would like to use WorkManager to update the DB every 24 hours from midnight.

首先，我知道 Workmanager 的 PeriodicWorkRequest 没有指定工作人员应该在任何给定时间操作。

所以我使用 OneTimeWorkRequest() 给出延迟，然后将 PeriodicWorkRequest() 放入队列中，该队列每 24 小时运行一次。

1.约束

private fun getConstraints(): Constraints {
    return Constraints.Builder()
            .setRequiredNetworkType(NetworkType.NOT_REQUIRED)
            .build()
}

2.OneTimeWorkRequest

fun applyMidnightWorker() {

    val onTimeDailyWorker = OneTimeWorkRequest
            .Builder(MidnightWorker::class.java)
            .setInitialDelay(getDelayTime(), TimeUnit.SECONDS)
            .setConstraints(getConstraints())
            .build()

    val workerContinuation =
            workManager.beginUniqueWork(Const.DAILY_WORKER_TAG,
                    ExistingWorkPolicy.KEEP,
                    onTimeDailyWorker)

    workerContinuation.enqueue()
}

getDelayTime() 是

private fun getDelayTime(): Long {
    ...
    return midNightTime - System.currentTimeMillis()
}

3.午夜 worker 类

class MidnightWorker : Worker() {

    override fun doWork(): Result {

        DailyWorkerUtil.applyDailyWorker()

        return Worker.Result.SUCCESS
    }
}

4.定期工作请求

fun applyDailyWorker() {

    val periodicWorkRequest = PeriodicWorkRequest
            .Builder(DailyWorker::class.java, 24, TimeUnit.HOURS)
            .addTag(Const.DAILY_WORKER)
            .setConstraints(getConstraints()).build()

    workManager.enqueue(periodicWorkRequest)

}

我确认 delayTime 过去了，midnightWorker 正在运行。

当然，它可以正常工作，与网络没有任何关系。

然而，测试结果表明延迟时间与设备时间无关。好像是服务器时间

This is my question.

1. No delay according to device time. I want to know if the delay works as per the server time standard.

2. I wonder if the PeriodicWorkRequest can provide InitialDelay like OneTimeWorkRequest.

Answer 1

你用过TimeUnit.SECONDS与 setInitialDelay还 getDelayTime正在使用毫秒。
这可能是你问题的原因