Android Interview Questions With Answer


1.What is android?

Android is a mobile operating system that is based on a modified version of Linux.It is available to anyone who wants to adapt it to run on their own devices.

2. October 26, 2009 Which version of Android came on this day ?

Eclair 2.1

3.What does API Stands for ?

application programming interfaces.

4.What Is features of android ?

  • Storage
  • Connectivity
  • Media support
  • Hardware support
  • Multi-touch
  • Multi-tasking
  • Tethering

5.What is AVD ?

Android Virtual Device (AVD)you can use for testing your Android applications. An AVD is an emulator instance that enables you to model an actual device. Each AVD consists of a hardware profile; a mapping to a system image; and emulated storage, such as a secure digital (SD) card.

6.Why was Jelly Bean selected for you by default in the Targeted Android Devices dialog ?

Jelly Bean was the most active version of Android on Google Play.

7. What is Setting Breakpoints ?

Breakpoints are a mechanism by which you can tell Android Studio to temporarily pause execution of your code.

8. What is Fragments ?

Fragments are “mini-activities” that you can add or remove from activities.

9. What is intents?

Intents Is The “glue” that connects different activities.There are two types of intents in android:
Implicit Intent
Explicit Intent

10. What is Use dp, sp, pt, and px?

dp—Density :-independent pixel. 1 dp is equivalent to one pixel on a 160 dpi screen. This is the recommended unit of measurement when you're specifying the dimension of views in your layout.

sp—Scale:- independent pixel. This is similar to dp and is recommended for specifying font sizes.

pt—Point:- A point is defined to be 1/72 of an inch, based on the physical screen size.

px—Pixel:- Corresponds to actual pixels on the screen. Using this unit is not recommended, as your UI might not render correctly on devices with a different screen resolution.

11. What is FrameLayout ?

The FrameLayout is the most basic of the Android layouts. FrameLayouts are built to hold one view. As with all things related to development, there is no hard rule that FrameLayouts can't be used to hold multiple views.

12. What is View ?

A view is a widget that has an appearance on screen. Examples of views are buttons, labels, and text boxes.

13. What is LinearLayout ?

LinearLayout Arranges views in a single column or single row.

14.What is RelativeLayout ?

RelativeLayout Enables you to specify how child views are positioned relative to each other.

15.What is AbsoluteLayout ?

AbsoluteLayout Enables you to specify the exact location of its children.

16. What is TableLayout ?

TableLayout Groups views into rows and columns.

17. What is PICKER VIEWS ?

Selecting a date and time is one of the common tasks you need to perform in a mobile application.

18. How many types of fragments ?

fragment are three types

  • ListFragment
  • DialogFragment
  • PreferenceFragment

19. What is ImageSwitcher ?

Using the ImageSwitcher view Performs animation when switching between images.

20. How to create service class ?

Create a class and extend the Service class.

21. What is Android Software Development Kit (SDK) ?

The Android Software Development Kit (SDK) provides a comprehensive set of tools that help the developer to build applications for Android. The SDK also offers tools for testing and debugging apps.

22. What is an Android Project ?

An Android project essentially consists of the entire source code for an Android application. The project helps to create an .apk file for installation of the application on any device.

23. What is AndroidManifest.xml ?

This is the most important file for each Android application. It is stored in the root folder of the application. It defines the components of the application, such as, services and activities.

24.What is android activities?

An activity represents the presentation layer. In other words, it is a screen containing the User Interface (UI). It allows the user to interact with the application.

25. What is Activity Lifecycle ?

The lifecycle of the activity changes depending on other related activities that are performed. Essentially when the activity is first initiated, the system calls certain lifecycle processes for the activity. The lifecycle processes for the original activity change when the user initiates an action that triggers another activity or accesses another application.

26. What is Services ?

It is a background component that processes lengthy operations, or is connected to processes that run remotely. Consider an example of music being played in the background while the user is surfing the net or checking emails.

27. What is Content Providers ?

Content providers are used for managing shared data sets. The data can be stored in the SQLite Database, Web, or other easily accessible storage location .

28. What is Android Manifest file ?

Android Manifest file is present in the root directory and presents information about the application to the Android system.

29. What is Android User Interface ?

User interface is what the user will see and interact with to perform some operations. Android comes with many friendly UI elements and layouts which helps to build interactive applications.

30.What is Attributes ?

Some attributes are specific to a View object - for example the TextView supports the textSize attribute. But these attributes are also inherited by any View objects that may extend this class. There are other attributes that are common to all View objects, because they are inherited from the root View class.

31. What is User Events ?

Event is a user interacting with the help of a Touchscreen. The Android framework maintains an Event Queue in which the events are arranged as they occur. The events are removed in First-In-First-Out (FIFO) basis.

32. What is Event Listener ?

Event listeners consist of a single callback method which are invoked when the view to which the listener is registered generates an event due to user interaction.