Android Interview Questions and Answers
Question - 81 : - What is AppCompatActivity?
Answer - 81 : -
AppCompatActivity is the base class for activities with the support library action bar features. ActionBar can be added to your activity by extending this class for your activity and setting the activity theme to Theme when running on API level 7 or higher.
Question - 82 : - What is Proguard?
Answer - 82 : -
Proguard detects and removes unused classes, fields, methods, and attributes. Mobile app development companies use the Proguard in android, it optimizes bytecode and removes unused instructions. It renames the remaining classes, fields, and methods by using short meaningless names.
Question - 83 : - What is taskAffinity?
Answer - 83 : -
An android application includes Activities that form a stack like a deck of cards. When you start an android application and start five activities A, B, C, D, E. Then they will form a stack such as:
A for the login screen
B for weather screen
C for map view
D for weather screen
E for chat view
Question - 84 : - What is Toast in Android?
Answer - 84 : -
Android Toast displays information for a short period of time that contains a message to be displayed quickly and disappears after some time. It also used to show notifications for a particular interval of time at the bottom of the screen by default.
Question - 85 : - How is data stored in Shared Preferences?
Answer - 85 : -
Shared Preferences persist data across user sessions that should be remembered across sessions, such as user’s preferred settings or their game score, even if the app is killed and restarted, or the device is rebooted.
Question - 86 : - What is a StateListDrawable?
Answer - 86 : -
StateListDrawable is a java class of Android, that is used for drawable contents in an application.
Question - 87 : - What is drawer layout in android?
Answer - 87 : -
The drawer Layout is the root layout. It defines a FrameLayout and a Navigation View. In Navigation View we set the items from the menu file and FrameLayout is used to replace the Fragments on the click of menu items.
Question - 88 : - What is Android Jetpack?
Answer - 88 : -
Android Jetpack is a set of Android components, tools, and guidance inspired by the backward compatibility of the Support Library and Android Architecture Components that are platform-independent, allowing your app to run on multiple Android platforms.
Question - 89 : - How to start/stop a service in Android?
Answer - 89 : -
You can Start android background service as follows:
Intent intent = new Intent(Activity.this, MyBackgroundService.class);
startService(intent);
You can Stop android background service as follows:
Intent intent = new Intent(Activity.this, MyBackgroundService.class);
stopService(intent);
Question - 90 : - What is Android Bound Service?
Answer - 90 : -
The bound service is a server in a client-server interface that allows components such as activities to bind to the service, send requests, receive responses, and perform interprocess communication (IPC).