使用 WorkManager 在特定时间安排工作

Question

WorkManager is a library used to enqueue work that is guaranteed to execute after its constraints are met.

因此，在早上通过 Constraints class I haven't found any function to add time constraint on the work. For like example, I want to start a work to perform at 8:00am (The work can be any of two types OneTimeWorkRequest or PeriodicWorkRequest) 之后。我如何添加约束以使用 WorkManager 安排这项工作。

Answer 1

很遗憾，您目前无法在特定时间安排工作。如果你有时间关键的实现，那么你应该使用 AlarmManager 来设置可以在打瞌睡时触发的警报，方法是使用 setAndAllowWhileIdle() or setExactAndAllowWhileIdle().

您可以使用 WorkManager 安排工作，使用一次性初始延迟或定期执行，如下所示：

创建工人class:

public class MyWorker extends Worker {
    @Override
    public Worker.WorkerResult doWork() {

        // Do the work here

        // Indicate success or failure with your return value:
        return WorkerResult.SUCCESS;

        // (Returning RETRY tells WorkManager to try this task again
        // later; FAILURE says not to try again.)
    }
}

然后安排OneTimeWorkRequest如下：

OneTimeWorkRequest mywork=
        new OneTimeWorkRequest.Builder(MyWorker.class)
        .setInitialDelay(<duration>, <TimeUnit>)// Use this when you want to add initial delay or schedule initial work to `OneTimeWorkRequest` e.g. setInitialDelay(2, TimeUnit.HOURS)
        .build();
WorkManager.getInstance().enqueue(mywork);

您可以按如下方式设置附加约束：

// Create a Constraints that defines when the task should run
Constraints myConstraints = new Constraints.Builder()
    .setRequiresDeviceIdle(true)
    .setRequiresCharging(true)
    // Many other constraints are available, see the
    // Constraints.Builder reference
     .build();

然后创建一个使用这些约束的 OneTimeWorkRequest

OneTimeWorkRequest mywork=
                new OneTimeWorkRequest.Builder(MyWorker.class)
     .setConstraints(myConstraints)
     .build();
WorkManager.getInstance().enqueue(mywork);

可以按如下方式创建PeriodicWorkRequest：

 PeriodicWorkRequest periodicWork = new PeriodicWorkRequest.Builder(MyWorker.class, 12, TimeUnit.HOURS)
                                   .build();
  WorkManager.getInstance().enqueue(periodicWork);

这会创建一个 PeriodicWorkRequest 运行每 12 小时定期一次。

Answer 2

到目前为止，使用 PeriodicWorkRequest.
无法获得准确的时间一个丑陋的解决方法是使用 OneTimeWorkRequest，当它触发时，设置另一个 OneTimeWorkRequest 和新的计算周期，依此类推。

Answer 3

您可以使用印象笔记中的 AndroidJob

class NotificationJob : DailyJob() {

override fun onRunDailyJob(params: Params): DailyJobResult {
       //your job       
       return DailyJobResult.SUCCESS

}

companion object {
    val TAG = "NotificationJob"
    fun scheduleJob() {
        //scheduled between 9-10 am

        DailyJob.schedule(JobRequest.Builder(TAG), 
            TimeUnit.HOURS.toMillis(9),TimeUnit.HOURS.toMillis(10 ))
     }
   }
 }

和通知创建者

  class NotificationJobCreator : JobCreator {

        override fun create(tag: String): Job? {
           return when (tag) {
              NotificationJob.TAG ->
                NotificationJob()
              else ->
                null
           }
       }
  }

然后在您的应用程序中启动 class

    JobManager.create(this).addJobCreator(NotificationJobCreator())

gradle 依赖项是

    dependencies {
        implementation 'com.evernote:android-job:1.2.6'

        // or this with workmnager 
        implementation 'com.evernote:android-job:1.3.0-alpha08'
    }

Answer 4

如果您想将初始延迟设置为 PeriodicWorkRequest，我在此处介绍了解决方案：

Set initial delay to a Periodic Work Manager in Android

Answer 5

所有答案现已过时，请升级到 WorkManager 2.1.0-alpha02（或更高版本） setInitialDelay() 方法过去只对 OneTimeWorkRequest 起作用，但现在它们也支持 PeriodicWorkRequest。

implementation "androidx.work:work-runtime:2.1.0-alpha02"

PeriodicWorkRequests now support initial delays. You can use the setInitialDelay method on PeriodicWorkRequest.Builder to set an initial delay

快速示例：

new PeriodicWorkRequest.Builder(MyWorker.class, MY_REPEATS, TimeUnit.HOURS)
        .setInitialDelay(THE_DELAY,TimeUnit.SECONDS);

Answer 6

从版本 2.1.0-alpha02 开始，PeriodicWorkRequests 现在支持初始延迟。您可以使用 PeriodicWorkRequest.Builder 上的 setInitialDelay 方法来设置初始延迟。 Link Here

每天上午 8:00 的时间表示例。这里我使用 joda time library 进行时间操作。

final int SELF_REMINDER_HOUR = 8;

    if (DateTime.now().getHourOfDay() < SELF_REMINDER_HOUR) {
        delay = new Duration(DateTime.now() , DateTime.now().withTimeAtStartOfDay().plusHours(SELF_REMINDER_HOUR)).getStandardMinutes();
    } else {
        delay = new Duration(DateTime.now() , DateTime.now().withTimeAtStartOfDay().plusDays(1).plusHours(SELF_REMINDER_HOUR)).getStandardMinutes();
    }


    PeriodicWorkRequest workRequest = new PeriodicWorkRequest.Builder(
        WorkerReminderPeriodic.class,
        24,
        TimeUnit.HOURS,
        PeriodicWorkRequest.MIN_PERIODIC_FLEX_MILLIS,
        TimeUnit.MILLISECONDS)
        .setInitialDelay(delay, TimeUnit.MINUTES)
        .addTag("send_reminder_periodic")
        .build();


    WorkManager.getInstance()
        .enqueueUniquePeriodicWork("send_reminder_periodic", ExistingPeriodicWorkPolicy.REPLACE, workRequest);

Answer 7

我可能有点晚了，但无论如何我这样做是为了在给定时间安排 WorkRequest（可选的短延迟）。您只需要从 TimePicker 中获取时间：

public static void scheduleWork(int hour, int minute) {
    Calendar calendar = Calendar.getInstance();
    long nowMillis = calendar.getTimeInMillis();

    if(calendar.get(Calendar.HOUR_OF_DAY) > hour ||
            (calendar.get(Calendar.HOUR_OF_DAY) == hour && calendar.get(Calendar.MINUTE)+1 >= minute)) {
        calendar.add(Calendar.DAY_OF_MONTH, 1);
    }

    calendar.set(Calendar.HOUR_OF_DAY,hour);
    calendar.set(Calendar.MINUTE,minute);

    calendar.set(Calendar.SECOND,0);
    calendar.set(Calendar.MILLISECOND,0);
    long diff = calendar.getTimeInMillis() - nowMillis;

    WorkManager mWorkManager = WorkManager.getInstance();
    Constraints constraints = new Constraints.Builder()
            .setRequiredNetworkType(NetworkType.CONNECTED)
            .build();
    mWorkManager.cancelAllWorkByTag(WORK_TAG);
    OneTimeWorkRequest mRequest = new OneTimeWorkRequest.Builder(NotificationWorker.class)
            .setConstraints(constraints)
            .setInitialDelay(diff,TimeUnit.MILLISECONDS)
            .addTag(WORK_TAG)
            .build();
    mWorkManager.enqueue(mRequest);

}

Answer 8

我试过 OneTimeWorkRequest 但它不稳定（有时只工作）所以我们不应该依赖它。 AlarmManager 是一个更好的选择。

使用 WorkManager 在特定时间安排工作

Schedule a work on a specific time with WorkManager

android

android-workmanager

您可以按如下方式设置附加约束：

可以按如下方式创建PeriodicWorkRequest：