Android.问题.DefaultLifecycleObserver not found

问题

今天重构代码发现如下问题

D:\...\TempManager.java:6: ����: �Ҳ�������
import androidx.lifecycle.DefaultLifecycleObserver;
                         ^
  ����:   �� DefaultLifecycleObserver
  �: ����� androidx.lifecycle

解决方法

dependencies {
    ...
    implementation 'androidx.core:core-ktx:1.5.0'
    implementation "androidx.lifecycle:lifecycle-common-java8:2.2.0"
}

加上这个依赖

implementation "androidx.lifecycle:lifecycle-common-java8:2.2.0"