为什么 Kotlin 的新 LiveData 构建器可能更新在我的项目中不起作用

Question

这是我的依赖项：

 //Room and Lifecycle Libraries
    kapt "androidx.room:room-compiler:2.2.0-alpha02"
    kapt 'androidx.room:room-compiler:2.2.0-alpha02'
    kapt "androidx.lifecycle:lifecycle-compiler:2.2.0-alpha03"
    implementation "androidx.room:room-runtime:2.2.0-alpha02"
    implementation 'androidx.room:room-runtime:2.2.0-alpha02'
    implementation "androidx.lifecycle:lifecycle-viewmodel:2.2.0-alpha03"
    implementation "androidx.lifecycle:lifecycle-extensions:2.2.0-alpha03"
    implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:2.2.0-alpha03"
    implementation "androidx.lifecycle:lifecycle-viewmodel-savedstate:1.0.0-alpha03"
    implementation 'com.jakewharton.retrofit:retrofit2-kotlin-coroutines-adapter:0.9.2'

如您所见，我实现了最终版本，但我无法访问 liveData 构建器。我怎样才能解决这个问题？

Answer 1

从文档：

对于liveData，使用androidx.lifecycle:lifecycle-livedata-ktx:2.2.0-alpha01或更高。

所以你只是缺少依赖：

implementation "androidx.lifecycle:lifecycle-livedata-ktx:2.2.0-alpha03"