Lifecycle添加依赖

在应用或模块的 build.gradle 文件中添加所需工件的依赖项：

lifecycle-extensions 中的 API 已弃用。您可以为特定 Lifecycle 工件添加所需的依赖项。

Kotlin

    dependencies {
        val lifecycle_version = "2.3.1"
        val arch_version = "2.1.0"

        // ViewModel
        implementation("androidx.lifecycle:lifecycle-viewmodel-ktx:$lifecycle_version")
        // LiveData
        implementation("androidx.lifecycle:lifecycle-livedata-ktx:$lifecycle_version")
        // 仅Lifecycles (没有 ViewModel 或 LiveData)
        implementation("androidx.lifecycle:lifecycle-runtime-ktx:$lifecycle_version")

        // 为 ViewModel 保存状态模块
        implementation("androidx.lifecycle:lifecycle-viewmodel-savedstate:$lifecycle_version")

        // Annotation processor（注释处理器）
        kapt("androidx.lifecycle:lifecycle-compiler:$lifecycle_version")
        // 或者 - 如果使用 Java8，请使用以下代码代替生命周期编译器
        implementation("androidx.lifecycle:lifecycle-common-java8:$lifecycle_version")

        // 可选 - 在服务中实现 LifecycleOwner 的助手
        implementation("androidx.lifecycle:lifecycle-service:$lifecycle_version")

        // 可选 - ProcessLifecycleOwner 为整个应用程序进程提供生命周期
        implementation("androidx.lifecycle:lifecycle-process:$lifecycle_version")
        // 可选 - 对 LiveData 的 ReactiveStreams 支持
        implementation("androidx.lifecycle:lifecycle-reactivestreams-ktx:$lifecycle_version")

        // 可选 - LiveData 的测试助手
        testImplementation("androidx.arch.core:core-testing:$arch_version")
    }
    

Java

    dependencies {
        val lifecycle_version = "2.3.1"
        val arch_version = "2.1.0"

        // ViewModel
        implementation("androidx.lifecycle:lifecycle-viewmodel:$lifecycle_version")
        // LiveData
        implementation("androidx.lifecycle:lifecycle-livedata:$lifecycle_version")
        // Lifecycles only (without ViewModel or LiveData)
        implementation("androidx.lifecycle:lifecycle-runtime:$lifecycle_version")

        // Saved state module for ViewModel
        implementation("androidx.lifecycle:lifecycle-viewmodel-savedstate:$lifecycle_version")

        // Annotation processor
        annotationProcessor("androidx.lifecycle:lifecycle-compiler:$lifecycle_version")
        // alternately - if using Java8, use the following instead of lifecycle-compiler
        implementation("androidx.lifecycle:lifecycle-common-java8:$lifecycle_version")

        // optional - helpers for implementing LifecycleOwner in a Service
        implementation("androidx.lifecycle:lifecycle-service:$lifecycle_version")

        // optional - ProcessLifecycleOwner provides a lifecycle for the whole application process
        implementation("androidx.lifecycle:lifecycle-process:$lifecycle_version")

        // optional - ReactiveStreams support for LiveData
        implementation("androidx.lifecycle:lifecycle-reactivestreams:$lifecycle_version")

        // optional - Test helpers for LiveData
        testImplementation("androidx.arch.core:core-testing:$arch_version")
    }