WorkManger Chaining Works

WorkManger에서 병렬로 work를 실행할려면 리스트로 work 넣어주면 된고

순차적으로 실행시킬려면 .then()으로 실행

package com.anushka.workmanagerdemo1

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.Toast
import androidx.lifecycle.Observer
import androidx.work.*
import kotlinx.android.synthetic.main.activity_main.*

class MainActivity : AppCompatActivity() {

    companion object{
    const val KEY_COUNT_VALUE = "key_count"
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        button.setOnClickListener {
            setOneTimeWorkRequest()
        }
    }

    private fun setOneTimeWorkRequest() {

        val workManager = WorkManager.getInstance(applicationContext)

        val data: Data = Data.Builder()
            .putInt(KEY_COUNT_VALUE,125)
            .build()
        val constraints = Constraints.Builder()
            .setRequiresCharging(true)
            .build()

        val uploadRequest = OneTimeWorkRequest.Builder(UploadWorker::class.java)
            .setConstraints(constraints)
            .setInputData(data)
            .build()

        val filteringRequest = OneTimeWorkRequest.Builder(FilteringWorker::class.java)
            .build()
        val compressingRequest= OneTimeWorkRequest.Builder(CompressingWorker::class.java)
            .build()
        val downloadingWorker= OneTimeWorkRequest.Builder(DownloadingWorker::class.java)
            .build()
        val paralleWorks = mutableListOf<OneTimeWorkRequest>()
        paralleWorks.add(downloadingWorker)
        paralleWorks.add(filteringRequest)
        workManager
            .beginWith(paralleWorks)
            .then(compressingRequest)
            .then(uploadRequest)
            .enqueue()

        workManager.getWorkInfoByIdLiveData(uploadRequest.id)
            .observe(this, Observer {
                textView.text = it.state.name
                if(it.state.isFinished){
                 val data = it.outputData
                 val message = data.getString(UploadWorker.KEY_WORKER)
                    Toast.makeText(applicationContext,message,Toast.LENGTH_LONG).show()
                }
            })


    }
}

worker

package com.anushka.workmanagerdemo1

import android.content.Context
import android.util.Log
import androidx.work.Data
import androidx.work.Worker
import androidx.work.WorkerParameters
import java.lang.Exception
import java.text.SimpleDateFormat
import java.util.*

class UploadWorker(context: Context,params:WorkerParameters) : Worker(context,params) {

    companion object{
        const val KEY_WORKER = "key_worker"
    }

    override fun doWork(): Result {
        try {
            val count = inputData.getInt(MainActivity.KEY_COUNT_VALUE,0)
            for (i in 0 until count) {
                Log.i("MYTAG", "Uploading $i")
            }

            val time = SimpleDateFormat("dd/M/yyyy hh:mm:ss")
            val currentDate = time.format(Date())

            val outPutData = Data.Builder()
                .putString(KEY_WORKER,currentDate)
                .build()

            return Result.success(outPutData)
        } catch (e:Exception){
            return Result.failure()
        }
    }
}