An overview of

JobScheduler is a task execution framework provided by the Android system. Through JobScheduler, we can schedule tasks based on different policies.

Such as:

  1. The specified task can be executed on the specified network
  2. Specified tasks can only be performed while charging
  3. Set the deadline of the task
  4. Specifies a delay for executing a task
  5. Specify tasks to be performed when the phone is idle

If the app is killed, the task cannot be executed. If you need to continue executing the task after restarting, it is recommended to use WorkManager

use

The basic use

Create a customized JobService and configure it in the manifest

class ExeTaskAfter2SecondService: JobService() {
    override fun onStartJob(params: JobParameters?).: Boolean {
        logEE("Five-second delay: onStartJob")
        return true
    }

    override fun onStopJob(params: JobParameters?).: Boolean {
        logEE("Five second delay: onStopJob")
        return true}}Copy the code
<service android:name=".service.ExeTaskAfter2SecondService"
            android:permission="android.permission.BIND_JOB_SERVICE"
            />
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Scheduling Task Execution

val mJobScheduler = getSystemService(JOB_SCHEDULER_SERVICE) as JobScheduler// Obtain system services
            val mBuilder = JobInfo.Builder(1, ComponentName(this, ExeTaskAfter2SecondService::class.java))//Builder the first parameter is the Job id, which can be used to cancel the task. The second parameter is the Service to execute the task logic
            var mJobInfo = mBuilder
                .setMinimumLatency(5000)// Execute the task after 5 seconds
                .build()
            mJobScheduler.schedule(mJobInfo)// The task is scheduled
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Canceling a Task

 mJobScheduler.cancel(1)// This id is the task ID specified in schedule
 mJobScheduler.cancelAll()// Cancel all tasks
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Set the deadline of the task

 var mJobInfo = mBuilder
                .setOverrideDeadline(5000)// It must be executed once within five seconds
                .build()
            mJobScheduler.schedule(mJobInfo)
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Set the network status of the task

Only on mobile networks

If we start the task without a wireless connection, we do not perform the task, and then we automatically start the network when we connect the wireless network

 val mBuilder = JobInfo.Builder(
                1,
                ComponentName(this, ExeTaskAfter2SecondService::class.java)
            )//Builder the first parameter is the Job id, which can be used to cancel the task. The second parameter is the Service to execute the task logic
            var mJobInfo = mBuilder
                .setRequiredNetworkType(JobInfo.NETWORK_TYPE_CELLULAR)
                .build()
            mJobScheduler.schedule(mJobInfo)// The task is scheduled
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Specify the limit of network traffic when a job is executed

We don’t think about traffic, so I didn’t test it

setEstimatedNetworkBytes (long downloadBytes, long uploadBytes)
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Run when the power is not low

setRequiresBatteryNotLow
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You must have a network connection to perform this operation

NETWORK_TYPE_ANY

Can be executed regardless of network availability

NETWORK_TYPE_NONE

This command can be executed only with wifi

NETWORK_TYPE_UNMETERED

Specify tasks to be performed when the phone is idle

setRequiresDeviceIdle

It’s hard to predict

 val mBuilder = JobInfo.Builder(
                1,
                ComponentName(this, ExeTaskAfter2SecondService::class.java)
            )//Builder the first parameter is the Job id, which can be used to cancel the task. The second parameter is the Service to execute the task logic
            var mJobInfo = mBuilder
SetOverrideDeadline (5000)// If the dealline time is set, setRequiresDeviceIdle will be executed even when the deadline is set
                .setRequiresDeviceIdle(true)
                .build()
            mJobScheduler.schedule(mJobInfo)// The task is scheduled
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This command can be executed only when the charging status is set

If we’re on a mission and the phone isn’t charged, the mission will start automatically when we plug it in

mJobScheduler = getSystemService(JOB_SCHEDULER_SERVICE) as JobScheduler
 val mBuilder = JobInfo.Builder(
                1,
                ComponentName(this, ExeTaskAfter2SecondService::class.java)
            )//Builder the first parameter is the Job id, which can be used to cancel the task. The second parameter is the Service to execute the task logic
            var mJobInfo = mBuilder
                .setRequiresCharging(true)// Set to charge
                .build()
            mJobScheduler.schedule(mJobInfo)// The task is scheduled
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The API is introduced

JobService.onStartJob

The onStartJob method is called when jobScheduler.schedule is called

The return value of the onStartJob method:

If false is returned, the task ends when the method completes, and the onStopJob method is not called later (even if we call cancel actively).

The method can be executed repeatedly if true is returned

JobService.onStopJob

Calling jobschdeuler. cancel triggers the onStopJob callback

JobService.jobFinished

jobFinished(params,false) : the first parameter JobParameters, the second parameter indicates whether to repeat the executionCopy the code

The active notification system has completed its task

Git:github.com/ananananzhu…