Android Interview Questions & Answers

Android Smartphones are the most widely used phones in the world. More than 2 million apps are present on Play Store for Android users. Thus, we can say that Android developers are in high demand. Following android interview questions will help you in preparing for an interview.

1) What is Android?

Android is the operating system that runs on smartphones, tablets, watches, televisions, and even in automobiles. It is based on Linux and open source.

2)What is the logic behind Android version naming?

Android version names are based on desserts. For example, Android version 5.0 is popularly known as Lollipop

3) What is the name of official IDE use for coding Android?

Android Studio

4) Which language is used for coding Android?

Java in Android SDK and C/C++ in Android NDK

5) Which build system used by the android studio?

Gradle

6) What do you mean by activity in android?

Activity is a window that contains user interface components like buttons, images, TextView, etc.

7) What is fragment in Android?

A Fragment is user interface part of an Activity. We can have more than one fragment in an activity.

8) What are the different lifecycle methods of activity?

onCreate(), onStart(), onResume(), onPause(), onStop(), onRestart(), and onDestroy()

9) Which XML attribute enable use to access view in Java code?

android:id

10) Name any three layout manager?

LinearLayout, RelativeLayout, and GridLayout

11) What is LinearLayout?

LinearLayout is a layout manager that arranges view in a single row or column. In other words, use to stack children horizontally or vertically.

12) What is RelativeLayout?

It is a view group that allows placing of views relative to each other.

13) What is Material Design in Android?

Material Design is a visual design guide to make the app beautiful and provide an amazing experience. It was introduced in Android Lollipop.

14) What is RecyclerView?

RecyclerView is considered a flexible version of ListView design to run the app efficiently.

15) What is CardView?

CardView is a view group that displays information in a card. It has rounded corners and shadow. It inherits FrameLayout class.

16) What do you mean by Intent in Android?

Intent enables us to communicate with different components present in Android.

17) What is the purpose of Intent?

  • To start an activity.
  • To deliver a broadcast.
  • To start a service.

18) How many types of Intent are there?

There are two types of Intent-

  1. Implicit Intent
  2. Explicit Intent

19) What do you mean by Implicit Intent?

In implicit intent, we do not specify a component name. Just indicate the action to be performed and data on which it is to be done.

20) What do you understand by Explicit Intent?

In this, we specify the recipient name. It is used to communicate with the components present in our app such as if we want to move between activities then we use explicit intent.

21) What is the importance of Intent Filter?

With the help of Intent Filter, we specify the intent in which the component is interested in receiving. It is specified in AndroidManifest.xml file.

22) How many types of logcats are there?

There are 5 logcats in Android which are-

  1. Debug
  2. Warn
  3. Info
  4. Verbose
  5. Error

23) How to make a Toast in Android?

Toast.makeText(getApplicationContext(), "Toast Example", Toast.LENGTH_LONG).show();

24) Where we declare permissions in android?

AndroidManifest.xml file is used to declare permissions.

25) Which class enables background operations and publish results on the UI thread?

AsyncTask

26) What methods of AsyncTask that must be overridden?

onPreExecute(), doInBackground(), onProgressUpdate(), onPostExecute()

27) What are the different storage techniques available in Android?

  • Using Shared Preference
  • Using Files
  • Storing SQLite

28) What do you mean by Shared Preference?

It is a way to store data in the form of key-value pair.

29) ______ is the database engine used in Android?

SQLite

30) What is Content Provider?

It is used to expose data to other application.

31) What do you mean by Broadcast Receiver?

This component of Android is used to listen for a particular event. It is specified in AndroidManifest.xml file.

32) What is Services in Android?

Use to run long running tasks that do not need user interaction.

33) What is the two popular image downloading and caching library in Android?

Picasso and Glide

34) Which library is used for fetching JSON data from internet?

Retrofit