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added in version 1.0.0

androidx.core.os

Interfaces

CancellationSignal.OnCancelListener Listens for cancellation. 
ParcelableCompatCreatorCallbacks<T> This interface was deprecated in API level 1.0.0. Use Parcelable.ClassLoaderCreator directly.  

Classes

BuildCompat This class contains additional platform version checking methods for targeting pre-release versions of Android. 
CancellationSignal Static library support version of the framework's CancellationSignal
ConfigurationCompat Helper class which allows access to properties of Configuration in a backward compatible fashion. 
EnvironmentCompat Helper for accessing features in Environment
HandlerCompat Helper for accessing features in Handler
LocaleListCompat Helper for accessing features in LocaleList
ParcelableCompat This class was deprecated in API level 1.0.0. Use Parcelable.ClassLoaderCreator directly.  
ParcelCompat Helper for accessing features in Parcel
TraceCompat Writes trace events to the system trace buffer. 
UserManagerCompat Helper for accessing features in UserManager in a backwards compatible fashion. 

Exceptions

OperationCanceledException An exception type that is thrown when an operation in progress is canceled.