1, the activity: interface, the user can operate on visual interface, all can see the interface in the application on the activity,
2, service: service, usually on the phone the background work, suitable for don't have to work with user interaction and long-term task,
3, ContentpProvider: content providers, refers to an application specific data sets available to other applications,
4, the Broadcast Receiver: radio Receiver, using the transfer of information between applications, can use radio Receiver for application to respond to external applications,

CodePudding user response:

The top right corner, please, write a blog