Activity state and fragment lifecycle in Android apps with Kotlin

In modern Android development, understanding the activity state and fragment lifecycle is crucial for implementing effective user interfaces and managing application behavior. Activities are Java classes responsible for managing the app's lifecycle, controlling transitions between different states triggered by user interactions or system events, with the MainActivity serving as the entry point. The activity lifecycle encompasses various states such as onCreate, onStart, onResume, onPause, onStop, and onDestroy, which dictate how an app behaves from launch to shutdown. Fragments, introduced to enhance UI flexibility on larger screens, represent manageable portions of an activity's UI, enabling multiple screens within a single activity. Although activities can exist independently, fragments require an activity to function, and their lifecycle is managed by FragmentManager. This tutorial explores the relationships and differences between activity states and fragment lifecycles, demonstrating how to create and manage fragments to promote modularity and code reuse in Android applications.