Android Interview Question

Android Studio 2.0 – Beta Features

  • Instant Run
  • Android Emulator
  • Google App Indexing Integration & Testing
  • Fast ADB
  • GPU Profiler Preview
  • Integration of IntelliJ 15

Download Android Studio 2.0 Beta

What are the code names of android?

  1. Alpha
  2. Beta
  3. Cupcake
  4. Donut
  5. Eclair
  6. Froyo
  7. Gingerbread
  8. Honycomb
  9. Ice Cream Sandwitch
  10. Jelly Bean
  11. Kitkat
  12. Lollipop
  13. Marshmallow
  14. Android N

What are the basic tools used to develop an android app?

  • JDK [Java Development Kit]
  • Android Studio OR Eclipse + ADT plugin [Recommended]
  • SDK Tools [Software Development Kit]

What are the core building Component/blocks of android?

Activity, View, Intent, AndroidMainifest.XML, Broadcast Receiver, Content Provider, Services and Fragment.

Android Software Stack

Linux kernel
Native libraries (middleware)
Android Runtime
Application Framework
Applications

What is the APK Format?

The Android packaging key is compressed with Classes,UI Components, Resources, Assets and manifest. All files are compressed to a single file is called APK.

What is AAPT?

AAPT is an acronym for android asset packaging tool. It handles the packaging process.

What is ANR?

ANR stands for Application Not Responding. It is a dialog box that appears if the application is no longer responding.

What is NDK?

NDK stands for Native Development Kit. By using NDK, you can develop a part of app using native language such as C/C++ to boost the performance.

What is ADB?

ADB stands for Android Debug Bridge. It is a command line tool that is used to communicate with the emulator instance.

What is Orientation?

Orientation, which can be set using setOrientation(), dictates if the LinearLayout is represented as a row or as a column. Values are set as either HORIZONTAL or VERTICAL.

Can we display HTML in TextView? If yes, then How?

myTextView.setText(Html.fromHtml("Web Technology This is Testing"));

How to put a border around an android textview?

What is .dex extension

Android programs are compiled into .dex (Dalvik Executable) files, which are in turn zipped into a single .apk file on the device. .dex files can be created by automatically translating compiled applications written in the Java programming language

What are Native Android Actions?

ACTION-ANSWER Opens an Activity that handles immediately initiates a call using the number supplied in
the Intent URI. Genereally it’s considered better from to use ACTION_DIAL if possible.
ACTION_DELETE Starts an Activity hat lets you delete the data specified at that Intent’s data URI.
ACTION_DIAL Brings up a dialer application with the number to dial pre-populated from the Intent URI. By
default this is handled by the native Android phone dialer.
ACTION_EDIT Requests an Activity that can edit that data at the specified Intent URI.
ACTION_INSERT
ACTION_PICK
ACTION_SEARCH
ACTION_SENDTO
ACTION_SEND
ACTION_VIEW
ACTION_WEB_SEARCH

What are the different phases of the Activity life cycle?

As an activity transitions from state to state, it is notified of the change by calls to the following protected methods:
1) void onCreate(Bundle savedInstanceState)
2) void onStart()
3) void onRestart()
4) void onResume()
5) void onPause()
6) void onStop()
7) void onDestroy()

What are the four essential states of an activity?

Active – if the activity is at the foreground
Paused – if the activity is at the background and still visible
Stopped – if the activity is not visible and therefore is hidden or obscured by another activity
Destroyed – when the activity process is killed or completed terminated

What are the different states wherein a process is based?

There are 4 possible states:

foreground activity
visible activity
background activity
empty process

What is the difference between a regular bitmap and a nine-patch image?

In general, a Nine-patch image allows resizing that can be used as background or other image size requirements for the target device. The Nine-patch refers to the way you can resize the image: 4 corners that are unscaled, 4 edges that are scaled in 1 axis, and the middle one that can be scaled into both axes.

What items are important in every Android project?

These are the essential items that are present each time an Android project is created:
– AndroidManifest.xml
– build.xml
– bin/
– src/
– res/
– assets/

Name some exceptions in android?

NullPointerException
ArithmeticException
InflateException
Surface.OutOfResourceException
SurfaceHolder.BadSurfaceTypeException
WindowManager.BadTokenException

What kind of layouts available in Android?

Android Layouts
Android LinearLayout
Android RelativeLayout
Android FrameLayout
Android TableLayout
Android ListView
Android GridView

What are the different storages available in android?

Shared Preferences
Internal Storage
External Storage,
SQLite Databases
Network Connection via web services

What is JSON Web Service?

JSON- Java Script Object Notation
JSON is very famous parsing for web services
Symbols use in JSON format
[ ] — Indicate array
{ } — Indicate object

Sample Format
 {
 "List":[
 {
 "Id":"1",
 "Name":"Android Tutorial"
 },
 {
 "Id":"1",
 "Name":"Android Development Interview Questions adn Answers"
 }
 ]
 }
 here, list indicates array and it has many objects with id and name filed.

Useful Resources for Android Application Development

Android Asset Studio– Useful to make drawable images for different types screens resolutions
Flat Icon– Easy to find free useful icons
Material Palette– Useful to get idea for choosing colors for material design
Android Arsenal– Largest collection of android useful libraries
Android Developer Blog– Get the latest news in android world
Pixel To DP Converter– Useful to convert from pixel to DP and vice versa.


Also published on Medium.