根據(jù)google官方demo，自己仿寫

google例子地址https://github.com/android/architecture-components-samples/tree/main/WorkManagerSample

MainActivity，調(diào)用位置

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        findViewById<Button>(R.id.click_btn).setOnClickListener {
            val continuation = TestOperations.Builder(this, "nihaoa"/*可以改為url地址等數(shù)據(jù)*/)
                .setFirstWorker(true)
                .setTwoWorker(true)
                .build()
            continuation.continuation.enqueue()
        }

    }
    //簡單的單任務處理
//    val myWorkRequest = OneTimeWorkRequestBuilder<GetNetData>()
//        .setInputData(workDataOf("ImageUrl" to "test"))
//        .setBackoffCriteria(
//            BackoffPolicy.LINEAR,
//            OneTimeWorkRequest.MIN_BACKOFF_MILLIS,
//            TimeUnit.MILLISECONDS
//        )
//        .build()
//
//    WorkManager.getInstance(this).enqueue(myWorkRequest)
}

BaseWorker類,用來做多個任務的組合，類似責任鏈模式

abstract class BaseWorker(context: Context, parameters: WorkerParameters) :
    CoroutineWorker(context, parameters) {
    override suspend fun doWork(): Result {
        val resourceUri = inputData.getString(Constants.KEY_IMAGE_URI)//獲取傳遞過來的數(shù)據(jù)
        try {
            applyFilter(resourceUri!!)
            return Result.success()
        } catch (throwable: Throwable) {
            return Result.failure()
        }
    }

    abstract fun applyFilter(input: String): String
}

FirstWroker類，第一個任務類，繼承BaseWorker，實現(xiàn)applyFilter方法

class FirstWroker(appContext: Context, workerParams: WorkerParameters) :
    BaseWorker(appContext, workerParams) {
    override fun applyFilter(input: String): String {
        var s = input+1;
        Log.d("testStr==1",s)
        return s
    }
}

TwoWorker類，第二個任務類，同樣繼承BaseWorker，實現(xiàn)applyFilter方法（和第一個沒什么區(qū)別）

class TwoWorker(context: Context, parameters: WorkerParameters) : BaseWorker(context, parameters) {
    override fun applyFilter(input: String): String {
        var s = input + 2
        Log.d("testStr==2", s)
        return s
    }
}

TestOperations類，管理工作流程，比較重要，如果是多任務模式

class TestOperations constructor(val continuation: WorkContinuation) {
    class Builder(val mContext: Context, val testStr: String) {
        private var startFirst1: Boolean = false
        private var startTow2: Boolean = false
        fun setFirstWorker(startFirst: Boolean): Builder {
            startFirst1 = startFirst//
            return this
        }

        fun setTwoWorker(startTow: Boolean): Builder {
            startTow2 = startTow
            return this
        }

        fun build(): TestOperations {
            var continuation = WorkManager.getInstance(mContext)
                .beginUniqueWork(
                    Constants.TEST_KEY,
                    ExistingWorkPolicy.REPLACE,
                    OneTimeWorkRequest.from(CancelWorker::class.java)
                )//創(chuàng)建并添加多任務，beginUniqueWork可以放入多個不重復的任務,beginWith可以放入重復的
            if (startFirst1) {
                val test = OneTimeWorkRequestBuilder<FirstWroker>()
                    .setInputData(createInputData())
                    .build()
                continuation = continuation.then(test)//添加第一個任務，由于每個都繼承BaseWorker，所以都會走Base的doWork方法
            }
            if (startTow2) {
                val test2 = OneTimeWorkRequestBuilder<TwoWorker>()
                    .setInputData(createInputData())
                    .build()
                continuation = continuation.then(test2)//添加第二個任務,由于每個都繼承BaseWorker，所以都會走Base的doWork方法
            }
            return TestOperations(continuation)//返回給MainActivity，使MainActivity可以控制什么時候使用enqueue入隊開啟
        }

        private fun createInputData(): Data {
            //鍵值對獲取地址參數(shù)，傳遞給不同的工作線程，比如google demo傳遞的是圖片地址，所以會依次對圖片做不同處理，順序執(zhí)行
            //如果為了獲取上一個處理完的結果數(shù)據(jù)，理論上是可以通過鍵值對存儲，依次修改，具體沒有測試過
            return workDataOf(Constants.KEY_IMAGE_URI to testStr)
        }
    }

}

Constants，通用KEY

object Constants {
    const val TEST_KEY:String = "test_key" ;

    const val KEY_IMAGE_URI = "KEY_IMAGE_URI"
}

CancelWorker，做一些準備工作

class CancelWorker(context: Context, workerParams: WorkerParameters) :
    Worker(context, workerParams) {
    override fun doWork(): Result {
        //做一些準備工作
        return Result.success()
    }

}