20 Most Frequently Asked Questions And Answers
If you are an Android application developer and looking for a job, then you must get well prepared for the questions that you will have to answer in the interview. Getting android development job isn’t easy at all. Since app development is becoming more and more popular due to its high-salary demand, more and more tech-savvy people are trying to make their way into this career. Hence, the best way to penetrate that clutter and get past it efficiently is by preparing one’s self in advance.
Although there are a lot of different questions asked in an interview regarding android development, following are some of the most common yet important ones that majority of interviewer simply can’t resist asking.
So, let’s wait no more and see what those important questions are.
- What is Android?
Android is an open-sourced operating system (OS) which is mainly used on mobile devices, such as smartphones and tablets. It is a Linux kernel-based system that has been equipped with rich components that authorizes developers to develop and run applications that are able to perform basic as well as advanced functions.
- What is the Android SDK?
The Android SDK is a set of tools needed by developers in order to develop applications on Android-supported devices. It has GUI that mirrors an Android environment, allowing developers to test and debug their application’s programmed codes.
Why emulator is important and required to work in the Android environment?
The emulator enables developers to play around an interface which serves and acts as an actual mobile device. Developers can write and execute their application codes to check and debug –if there is any problem. In short, emulator provides developers with a safe environment where they can test their codes.
- What is a Splash screen?
The splash screen is the startup display that we see when the devise is switched on. It usually displays either the of the device’s brand or some other effects.
- What is .apk extension in android?
APK, also known as Application Package, is a default file format that android applications use- just like any other platform for instance .dll for Windows. The extension signifies a file type that contains a compressed data of resource files and other codes that help android run an application on its platform.
- When it comes to android, how many methods can be used to store data?
There are basically 5 ways one may store data in an android system and they include: Sqlite Database, Internal Store, External Store, Network Connection and Shared Preferences.
- What are the main components Android Architecture?
Android Architecture is consisted of four main components:
a) Linux Kernel
c) Android Framework
d) Android Applications
- Define Android Framework.
The Android Framework is spine of the Android Architecture. You can get to know all the methods and classes that developer will require to write programming codes of Android applications.
- What part activityCreator plays?
An activityCreator is your initial step towards the new Android project. ActivityCreator is nothing but a script that is used to develop new file system structure which is required to write codes in Android IDE.
- What is meant by Activities?
Activities are similar to windows which are used to display output or to take input in the form of dialog boxes.
- Define Intents.
Intents show notifications to the client from within the Android enabled devices and can be responded back by the users, as well.
Describe AAPT and its functioning?
AAPT (Android Asset Packaging Tool) is a tool that makes developers capable of dealing with zip-compatible archives, including extracting, creating as well as viewing the contents.
- What is ADB?
ADB (Android Debug Bridge) gives app developers control over communication towards and from the emulator port.
- How many essential states of activities are there?
Following are the three essential states of activities:
Paused – In case the activity is running at background but still visible
Stopped –In case the activity is invisible or obscured by another activity
Destroyed –In case the activity is completely terminated
- What is the difference between services and activities?
Services run behind the scenes, having the ability to act alone. Most of the services keep on running continuously, regardless of whether there are certain activities being executed or not. Whereas, activities can be terminated or closed by the user anytime he/she wants to.
- Name the components required for every Android project.
Following are the essential components that are required every single time you want to create a new Android project:
- Why XML-based layouts are important?
The XML-based layouts are considered important because they provide basic means of GUI definition format. Generally, layout details are backed-up in XML files while others in source files.
- What is the role of Android in current mobile market?
Android gives freedom to developers to write and register their own apps which can be installed and run on any Android supported mobile device or gadget. Therefore, the developers can make the most of rapidly growing demand of Android by developing and uploading their apps on Android market. The developer can decide on his own whether he wants to make his apps paid, free or both.
- Define ANR?
ANR (Application Not Responding) is a basic dialogue box that pop-ups whenever an application does not respond.
- What are the three main loops of monitoring an activity?
Following are the three main loops of monitoring an activity:
Entire Lifetime –When an activity happens between onDestroy & onCreate
Visible Lifetime –When an activity happens between onStart & onStop
Foreground Lifetime –When an activity happens between onResume & onPause
- What are the four possible states of a process?
Given below are the four possible states of a process:
- Empty Process