HiltWorkerFactory:在AppStartup上配置WorkManagerInitializer

Question

WorkManagerInitializer需要配置setWorkerFactory以向Worker类注入依赖项。本文档介绍了AppStartup中的workManager初始化，但未提供有关如何配置setWorkerFactory的详细信息。如果有人能提出任何解决方案或变通办法，那将是非常有帮助的。问题是我无法将自己的依赖项注入到workerClass中。下面我有两个场景来解释这个案例：`工作场景#1：

//此调用可以正常工作。

class AppWorker @WorkerInject constructor(
    @Assisted context: Context,
    @Assisted workerParams: WorkerParameters
) : Worker(context, workerParams) {
    companion object {
        val workType = "WorkType"

    }

    override fun doWork(): Result {
        return Result.success()
    }
}

失败的场景#2：

// Initializes WorkManager.
class WorkManagerInitializer : Initializer<WorkManager> {
    override fun create(context: Context): WorkManager { 
        // How to get workFactory required for configuration.
        var workerFactory: HiltWorkerFactory? = null
        val configuration = Configuration.Builder()
            .setWorkerFactory(workerFactory)
            .build()
        WorkManager.initialize(context, configuration)
        return WorkManager.getInstance(context)
    }

    override fun dependencies(): List<Class<out Initializer<*>>> {
        // No dependencies on other libraries.
        return emptyList()
    }
}



@HiltAndroidApp
class BaseApp: Application(),Configuration.Provider{
    @Inject lateinit var workerFactory: HiltWorkerFactory
    override fun getWorkManagerConfiguration() =
        Configuration.Builder()
            .setWorkerFactory(workerFactory)
            .build()
    init {
        Thread.setDefaultUncaughtExceptionHandler(ThreadExceptionalHandler())

    }
    override fun onCreate() {
        super.onCreate()
        if (BuildConfig.DEBUG) {
            Timber.plant(DebugTree())
        }
    }
}

Manifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    package="com.example.baseapp">

      <application
        android:name="com.example.baseapp.startup.BaseApp"
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.MyApp"
        >
        <activity android:name="com.example.baseapp.gui.activities.MainActivity"
            android:screenOrientation="portrait">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

    <provider
            android:name="androidx.startup.InitializationProvider"
            android:authorities="${applicationId}.androidx-startup"
            android:exported="false"
            tools:node="merge">

            <meta-data                android:name="com.example.baseapp.startup.AppServicesInitializer"
                android:value="androidx.startup" />

        </provider>
        <provider
            android:name="androidx.work.impl.WorkManagerInitializer"
            android:authorities="${applicationId}.workmanager-init"
            tools:node="remove"/>

    </application>

</manifest>

// App合规运行成功，但调用doWork()失败

  [1]: https://developer.android.com/topic/libraries/app-startup
The AppWorker class dowork() method is not getting called with WorkManagerInitializer defined at AppStartup. Here is the error in logcat:

2020-09-24 19:38:41.811 23803-23863/com.example.baseapp E/WM-WorkerFactory: Could not instantiate com.example.baselib.services.local.work_manager.worker.AppWorker
java.lang.NoSuchMethodException: com.example.baselib.services.local.work_manager.worker.AppWorker.<init> [class android.content.Context, class androidx.work.WorkerParameters]
    at java.lang.Class.getConstructor0(Class.java:2332)
    at java.lang.Class.getDeclaredConstructor(Class.java:2170)
    at androidx.work.WorkerFactory.createWorkerWithDefaultFallback(WorkerFactory.java:95)
    at androidx.work.impl.WorkerWrapper.runWorker(WorkerWrapper.java:242)
    at androidx.work.impl.WorkerWrapper.run(WorkerWrapper.java:136)
    at androidx.work.impl.utils.SerialExecutor$Task.run(SerialExecutor.java:91)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
    at java.lang.Thread.run(Thread.java:923)

Answer 1

对于使用带有androidx.work-* 2.6.0-alpha01或更高版本的Hilt的用户：

从release notes开始，这个版本在内部使用了新的androidx.startup jetpack库。因此，从AndroidManifest.xml中删除WorkManager的默认初始化器的方法发生了一些变化。

如果您在应用程序的其他位置使用androidx.startup，请将old change替换为：

<provider
    android:name="androidx.startup.InitializationProvider"
    android:authorities="${applicationId}.androidx-startup"
    android:exported="false"
    tools:node="merge">
    <!-- If you are using androidx.startup to initialize other components -->
    <meta-data
        android:name="androidx.work.impl.WorkManagerInitializer"
        android:value="androidx.startup"
        tools:node="remove" />
 </provider>

否则，您可以通过将旧更改替换为以下内容来完全禁用androidx.startup：

<!-- If you want to disable androidx.startup completely. -->
<provider
    android:name="androidx.startup.InitializationProvider"
    android:authorities="${applicationId}.androidx-startup"
    tools:node="remove">
</provider>

这样，您的HiltWorker将再次使用您的子类应用程序中的工厂。不幸的是，您将失去延迟启动的(明显)好处。

Answer 2

您可以通过使用如下所示的@WorkerInject注释来简单地注入依赖项，并摆脱工厂：

class ExampleWorker @WorkerInject constructor(
  @Assisted appContext: Context,
  @Assisted workerParams: WorkerParameters,
  dependency: YourClassDependency
) : Worker(appContext, workerParams) { ... }

然后，让您的Application类实现Configuration.Provider接口，注入一个HiltWorkFactory实例，并将其传递到WorkManager配置中，如下所示：

@HiltAndroidApp
class ExampleApplication : Application(), Configuration.Provider {

  @Inject lateinit var workerFactory: HiltWorkerFactory

  override fun getWorkManagerConfiguration() =
      Configuration.Builder()
            .setWorkerFactory(workerFactory)
            .build()
}

请注意，还必须从AndroidManifest.xml中删除缺省初始值设定项

<application>
  <provider
      android:name="androidx.work.impl.WorkManagerInitializer"
      android:authorities="${applicationId}.workmanager-init"
      tools:node="remove" />
</application>

参考：Hilt and Jetpack Integrations

Answer 3

我们可以直接从Initializer中使用HiltWorkerFactory。示例如下：

class CustomWorkManagerInitializer : Initializer<WorkManager> {

    override fun create(context: Context): WorkManager {
        val workerFactory = getWorkerFactory(appContext = context.applicationContext)
        val config = Configuration.Builder()
            .setWorkerFactory(workerFactory)
            .build()
        WorkManager.initialize(context, config)
        return WorkManager.getInstance(context)
    }

    override fun dependencies(): MutableList<Class<out Initializer<*>>> = mutableListOf()

    private fun getWorkerFactory(appContext: Context): HiltWorkerFactory {
        val workManagerEntryPoint = EntryPointAccessors.fromApplication(
            appContext,
            WorkManagerInitializerEntryPoint::class.java
        )
        return workManagerEntryPoint.hiltWorkerFactory()
    }

    @InstallIn(SingletonComponent::class)
    @EntryPoint
    interface WorkManagerInitializerEntryPoint {
        fun hiltWorkerFactory(): HiltWorkerFactory
    }
}

删除应用程序中的HiltWorkerFactory注入。

@HiltAndroidApp
class BaseApp : Application() {
    override fun onCreate() {
        super.onCreate()
        AppInitializer.getInstance(this).initializeComponent(CustomWorkManagerInitializer::class.java)
    }
}

另外，禁用默认的WorkManager初始化器，并在清单中添加我们的自定义。

<provider
        android:name="androidx.startup.InitializationProvider"
        android:authorities="${applicationId}.androidx-startup"
        android:exported="false"
        tools:node="merge">
        <!-- disable default -->
        <meta-data
            android:name="androidx.work.WorkManagerInitializer"
            android:value="@string/androidx_startup"
            tools:node="remove" />
        <!-- enable custom -->
        <meta-data
            android:name="com.acme.app.initializer.CustomWorkManagerInitializer"
            android:value="androidx.startup" />
</provider>