This callback is called when the activity restarts after stopping it. This callback is called before the activity is destroyed by the system. This callback is called when the activity is no longer visible. The paused activity does not receive user input and cannot execute any code and called when the current activity is being paused and the previous activity is being resumed.

This is called when the user starts interacting with the application.

This callback is called when the activity becomes visible to the user. This is the first callback and called when the activity is first created. However, it's important that you understand each one and implement those that ensure your app behaves the way users expect. You don't need to implement all the callbacks methods. The Activity class defines the following call backs i.e.

There is a sequence of callback methods that start up an activity and a sequence of callback methods that tear down an activity as shown in the below Activity life cycle diagram: ( image courtesy : ) Very similar way, Android system initiates its program with in an Activity starting with a call on onCreate() callback method. If you have worked with C, C++ or Java programming language then you must have seen that your program starts from main() function. An activity represents a single screen with a user interface just like window or frame of Java.Android activity is the subclass of ContextThemeWrapper class.

Android studio theme activity