如何修复未解析的引用 lifecycleScope？

Question

尝试构建一个在 activity 中使用 kotlin 协程的简单示例：

   lifecycleScope.launch {
             val result = httpGet("http://hmkcode-api.appspot.com/rest/api/hello/Android")
              textView.setText(result)
   }

无法摆脱错误"unresolved reference lifecycleScope"

gradle 文件的相关部分：

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'



dependencies {

implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.2'
implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.3.2'
implementation "org.jetbrains.kotlinx:kotlinx-coroutines-rx2:1.3.2"

def androidArchVersion = '1.1.1'
implementation "android.arch.lifecycle:viewmodel:$androidArchVersion"
implementation "android.arch.lifecycle:livedata:$androidArchVersion"
annotationProcessor "android.arch.lifecycle:compiler:$androidArchVersion"
testImplementation "android.arch.core:core-testing:$androidArchVersion"
implementation "android.arch.lifecycle:extensions:$androidArchVersion"
}

kotlinOptions {
    jvmTarget = '1.8'
    apiVersion = '1.3'
    languageVersion = '1.3'
}

}

Answer 1

根据 Lifecycle KTX documentation，如果您想要特定于协程的扩展，则必须包含 lifecycle-runtime-ktx 工件。

请注意，lifecycle-runtime-ktx 仅在 Lifecycle 2.2.0, so you'll need to Migrate to AndroidX 中引入，如果您想使用该功能，请升级到生命周期 2.2.0。

Answer 2

这里回复晚了，但我也遇到了这个问题，最后设法通过将继承的 Android Activity 更改为 AppCompatActivity.

来解决它

如何修复未解析的引用 lifecycleScope？

how to fix unresolved reference lifecycleScope?

android

gradle

kotlin

build.gradle

kotlin-coroutines