lifecycleManagerObserver
Return
The LifecycleManagerObserver that only reports the lifecycle of this AppCompatActivity. Will be created if need but only one instance will exist.
For example can be used by code in the Activity itself.
Warning: do not use this attempt to use this observer in cases where a dependent class such a Builder exists over the lifespan of several Activities (e.g. when recreated due to rotation etc). In particular this applies to places such as a ViewModel, which can outlive a single Activity.