Interview Questions for Android

A lot of final year students and graduates looking for placements in Android Application development are curious to know about android interview questions what employers ask in interviews. At times subject matter technical Interviews are not just restricted to the subject but employers also check the candidate’s fundamental knowledge, ability to think logically as well as practical ( hands-on ability to code given a time limit).The Interview rounds are also followed by HR questions checks the candidate’s interest to join the organization, grow with the organization, team spirit, and ability to mold and take up different challenges. Following are the rounds that take place in a given organization: Aptitude ( check logical reasoning)rnNot all companies have this level of an interview processrnFundamentalsrnCovers OOPS, SQL query as well as fundamentalrnAll companies usually have this round as the first initial level of screeningrnSubject Matter ( technical and Practical Subjects related to Android Application Development)rnAdvanced Subject Matter QuestionsrnThis round basically decides the salary at which a company is ready to hire the candidate. Most of the candidates that have undergone professional training outside of colleges can clear the Fundamentals and Subject matter rounds. The Advance rounds help differentiate the knowledge and exposure based on the projects students have undertakenrnHR roundsrnTOPS Technologies trains a lot of students in Android application development and have placed them in different IT companies with salaries ranging from 1.5 L CTC to 3.5 L CTC. TOPS Technologies have compiled interview questions on android based on the feedbacks given by different companies and our students on the questions they faced. The questions contain the above categories with answers to make sure candidates can thoroughly prepare the same. List Of Android Question And Answer 1. What is Android? Ans: Android is Linux based Open source Mobile operating system used in Smart phones, Tablets, TV, Automobiles, and Watch etc. 2. What is view Android application? Ans: View is base class of widgets, Rectangular area of screen. View is responsible for drawing and event handling. 3. List of out the each method of Activity lifecycle in android ? Ans : In Android application have the below stage of life cycle method – OnCreate() OnStart() OnResume() OnPause() OnRestart() OnStop() OnDestroy() 4. List out the Fragment lifecycle in Android ? Ans: Following methods will generate on different stages of fragment lifecycle. OnAttach() OnCreate() OnCreateView() OnCreateView() OnViewCreated() OnStart() OnResume() OnPause() OnStop() OnDestroyView() OnDestroy() OnDetach() 5. What is Difference between linear and relative layout in Android ? Ans: Linear Layout – it will show sub layouts in Linear form (Vertical and Horizontal) . Relative Layout: This layout will set its components by relating to each other and also by giving dependency. 6. How to set two layout which equal width and height on View in Android ? Ans: With use of Linear Layout we have weight attribute to set equal height and width. 7. How many Components in Android which are using to build an Application? Ans: When we create android application below components will be used – View Activity Service Broadcast Receiver Content Provider 8. What is Service in Android ? Ans: Service is background task of any application which runs in background. A downloading task, MusicPlayer Task. 9. What is intent in Android Application? Ans: Intent is an object which defines to execute any action intentionally. Two types of intent in android. (i) Explicit Intent: this intent define when we want to call another activity from current activity in same application. (ii) Implicit Intent. 10. Which class is using to complete long task in background? Ans: We can use below class and method to complete long background task – AsyncTask with help of its three methods, onPreExecutes onPostExecutes doInBackground 11. Where we can store offline data in android Application? Ans: Data will be stored in local database using SQLite. 12. What is Gradle in Android? Ans: Gradle is script in which we define third party library dependencies, class paths and it will compile all files without project. 13. If you have to use services of any online shopping website so you have to configure in every activity or to create any class file? Ans: We can define service handler class to establish HTTP Url connection, then in each activity where we want to show data from database we just change URL of our web service API. 14. What is view pager in android Application? Ans: The View Pager is providing swiping gesture in android, ex. Tab Layout. 15. Difference between picaso and glide Library in Android ? Ans: Picasso library can only load image, where glide can also load gif format. 16. What is GSON in Android ? Ans: GSON is converter library, which convert Json array and objects when we work with retrofit. 17. What is JsonParsing ? Ans: Json stands for Javascript object notation, a format for data exchange from the server. In Android, when we work with online database, we need to convert table data into JSON data, and to manipulate those data Android provide different way for JSON Parsing. HTTP Url connection, Retrofit, Volly etc. 18. Difference between activity and fragment in Android? Ans Activity is direct user interaction screen in which all components and events are generated. Every application has at least one Activity. A fragment is part of an activity, which inflated on activity’s layout. We can use multiple fragments inside single activity. Fragments are faster in a transaction than activity. 19. Can we use more than one fragments in single activity? Ans: Yes. 20. How many data can we get from facebook API ? Ans: Using graph library and Profile class, we can get all information of a user. ex Name, first name, last name, profile image, middle name 21.Which 3rd party library you have used in Android? Ans: Retrofit, Picasso, Glide, volly. 22. Why use Retrofit in Android? Ans: Retrofit will return appropriate response very faster than HTTP, Volly. 23. In Hangout application, if data is more than 5000 at that time which adapter view is the best for memory management? Ans: Recycler View 24. Write code for fetching JSON array in Android? Ans: JSONArray array = new JSONArray(result); for(int i=0;i