Techalert

Top 20 Android Interview Questions And Answers

<div dir="ltr" style="text-align: left;" trbidi="on">
<div>
Android is a mobile <b>operating system</b> (OS) based on the <b>Linux kernel</b> and currently developed by Google. With a user interface based on direct manipulation, Android is designed primarily for <b>touchscreen mobile devices</b> such as smartphones and tablet computers, with specialized user interfaces for televisions (Android TV), cars (Android Auto), and wrist watches (Android Wear). </div>
<div>
<br /></div>
<div>
The OS uses touch inputs that loosely correspond to real-world actions, like swiping, tapping, pinching, and reverse pinching to manipulate on-screen objects, and a virtual keyboard.<br />
<br />
Despite being primarily designed for touchscreen input, it also has been used in game consoles, digital cameras, regular PCs (e.g. the HP Slate 21) and other electronics.<br />
<br />
<div style="text-align: center;">
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh45rorjX_pDo-Tw6INR0zyu0-Aczh5p-k7bZU9ClD-UWQPPPLzjh22lqwOhSdHi8eH1PrMFhYoPKYJlUmEqO_euYxvHjohEpARJFEIrPOyPdaTX2FMc8qDh_0GCs5Mv12cnw7at4UdbQ/s1600/android-interview.jpg" style="margin-left: 1em; margin-right: 1em;"><img alt="Android Interview" border="0" height="260" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh45rorjX_pDo-Tw6INR0zyu0-Aczh5p-k7bZU9ClD-UWQPPPLzjh22lqwOhSdHi8eH1PrMFhYoPKYJlUmEqO_euYxvHjohEpARJFEIrPOyPdaTX2FMc8qDh_0GCs5Mv12cnw7at4UdbQ/s1600/android-interview.jpg" title="Android Interview" width="550" /></a></div>
</div>
</div>
<br />
<div style="text-align: center;">
<div style="text-align: left;">
<h3 style="text-align: left;">
<span face="" style="color: #6aa84f;"><span style="font-size: 17px;">List of <b>Most frequently Asked Android </b></span></span><span face="" style="color: #6aa84f; font-size: 17px;"><b>Interview Questions and Answers </b>for freshers and experienced are below:</span></h3>
</div>
</div>
<br />
<b>1. What is meaning of Android Word?</b><br />
it means a robot with a human appearance.<br />
<br />
<b>2. What is Android?</b><br />
an open-source operating system used for smartphones and tablet computers.<br />
<br />
<b>3. Inventors of android ?</b><br />
Andy Rubin, Rich Miner, Nick Sears<br />
<br />
<b>4. Android versions history and there name?</b><br />
<br />
<table style="background-color: #f7f7f7; border-collapse: collapse; border-spacing: 0px; border: 0px; color: #222222; font-family: roboto, sans-serif; font-size: 14px; line-height: 19px; margin: 0.5em 0px 1em 1em; width: 600px;"><thead>
<tr><th style="background-color: #999999; border: 1px solid rgb(221, 221, 221); color: white; font-weight: normal; padding: 4px 12px; vertical-align: top;">Code name</th><th style="background-color: #999999; border: 1px solid rgb(221, 221, 221); color: white; font-weight: normal; padding: 4px 12px; vertical-align: top;">Version</th><th style="background-color: #999999; border: 1px solid rgb(221, 221, 221); color: white; font-weight: normal; padding: 4px 12px; vertical-align: top;">API level</th></tr>
</thead><tbody>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Lollipop</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">5.0</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 21</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">KitKat</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">4.4 - 4.4.4</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 19</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Jelly Bean</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">4.3.x</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 18</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Jelly Bean</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">4.2.x</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 17</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Jelly Bean</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">4.1.x</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 16</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Ice Cream Sandwich</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">4.0.3 - 4.0.4</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 15, NDK 8</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Ice Cream Sandwich</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">4.0.1 - 4.0.2</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 14, NDK 7</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Honeycomb</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">3.2.x</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 13</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Honeycomb</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">3.1</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 12, NDK 6</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Honeycomb</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">3.0</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 11</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Gingerbread</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">2.3.3 - 2.3.7</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 10</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Gingerbread</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">2.3 - 2.3.2</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 9, NDK 5</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Froyo</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">2.2.x</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 8, NDK 4</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Eclair</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">2.1</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 7, NDK 3</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Eclair</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">2.0.1</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 6</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Eclair</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">2.0</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 5</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Donut</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">1.6</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 4, NDK 2</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">Cupcake</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">1.5</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 3, NDK 1</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">(no code name)</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">1.1</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 2</td></tr>
<tr><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">(no code name)</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">1.0</td><td style="background-color: inherit; border: 1px solid rgb(221, 221, 221); padding: 4px 12px; vertical-align: top;">API level 1</td></tr>
</tbody></table>
<br />
<b>5. Features of Android OS?</b><br />
Most of us are aware of features like <br />
Live wallpaper<br />
Camera<br />
Messaging<br />
Bluetooth<br />
WIFI<br />
Web Browsing<br />
Music<br />
Alarm etc. etc….<br />
<div style="text-align: center;">
<b style="background-color: white; color: #333333; font-family: verdana, geneva, sans-serif; font-size: 12px; line-height: 19.2px;"><span style="color: #990000;">Also Read:</span> <a href="http://itechaleart.blogspot.com/2014/04/top-50-common-interview-qa.html" style="color: #999999; text-decoration: none;"><span style="color: #3d85c6;">Top 50 Common Job Interview Questions and answers</span></a></b></div>
<br />
<b>6. Advance Features of Android OS?</b><br />
Google now (voice assistant)<br />
NFC (Near Field Communication)<br />
Unlock your phone by your face<br />
Use your phone with joystick to enjoy gaming experience<br />
Connect your phone with LED TV via MHL or micro HDMI cable<br />
Screen Capture<br />
Multitasking Future (Task Switcher)<br />
Data Usages (Check and also set limit from device)<br />
<br />
<b>7. Tools Required for Developing Android Apps?  </b><br />
JDK<br />
<div>
Eclipse + ADT plugin</div>
SDK Tools.<br />
<br />
You can also use <a href="http://developer.android.com/sdk/index.html" target="_blank">Android Studio</a> by Google.<br />
<div>
<br /></div>
<b>8. ADT stand for?</b><br />
Android Developer Tools<br />
<br />
<b>9. SDK stand for ?</b><br />
Software Development Kit<br />
<br />
<b>10. Advantages of android?</b><br />
Open-source<br />
Platform-independent<br />
Supports various technologies (having number of native application like: camera, bluetooth, wifi, speech, EDGE)<br />
<br />
<div style="text-align: center;">
<b style="background-color: white; color: #333333; font-family: verdana, geneva, sans-serif; font-size: 12px; line-height: 19.2px;"><span style="color: #990000;">Also Read:</span> <a href="http://itechaleart.blogspot.com/2013/06/top-50-oop-interview-questions.html" style="color: #999999; text-decoration: none;"><span style="color: #3d85c6;">Top 50 OOPs Interview Questions and Answers</span></a></b></div>
<br />
<b>11. Language Know to develop android apps?</b><br />
Java<br />
XML<br />
<div>
<br /></div>
<b>12. Android application main components are?</b><br />
<table class="src" style="background-color: #f7f7f7; border-collapse: collapse; border: 1px solid rgb(214, 214, 214); color: black; font-family: helvetica, arial, sans-serif; font-size: 12px; margin: 8px 0px; padding: 0px; vertical-align: top; width: 560px;"><tbody style="margin: 0px; padding: 0px;">
<tr style="margin: 0px; padding: 0px;"><th style="background-color: #eeeeee; border-collapse: collapse; border: 1px solid rgb(214, 214, 214); margin: 0px; padding: 5px; width: 129px;">Components</th><th style="background-color: #eeeeee; border-collapse: collapse; border: 1px solid rgb(214, 214, 214); margin: 0px; padding: 5px;">Description</th></tr>
<tr style="margin: 0px; padding: 0px;"><td style="border-collapse: collapse; border: 1px solid rgb(214, 214, 214); margin: 0px; padding: 5px;">Activities</td><td style="border-collapse: collapse; border: 1px solid rgb(214, 214, 214); margin: 0px; padding: 5px;">They dictate the UI and handle the user interaction to the smartphone screen</td></tr>
<tr style="margin: 0px; padding: 0px;"><td style="border-collapse: collapse; border: 1px solid rgb(214, 214, 214); margin: 0px; padding: 5px;">Services</td><td style="border-collapse: collapse; border: 1px solid rgb(214, 214, 214); margin: 0px; padding: 5px;">They handle background processing associated with an application.</td></tr>
<tr style="margin: 0px; padding: 0px;"><td style="border-collapse: collapse; border: 1px solid rgb(214, 214, 214); margin: 0px; padding: 5px;">Broadcast Receivers</td><td style="border-collapse: collapse; border: 1px solid rgb(214, 214, 214); margin: 0px; padding: 5px;">They handle communication between Android OS and applications.</td></tr>
<tr style="margin: 0px; padding: 0px;"><td style="border-collapse: collapse; border: 1px solid rgb(214, 214, 214); margin: 0px; padding: 5px;">Content Providers</td><td style="border-collapse: collapse; border: 1px solid rgb(214, 214, 214); margin: 0px; padding: 5px;">They handle data and database management issues.</td></tr>
</tbody></table>
<br />
<b>13. What is Activities?</b><br />
An activity is a single, focused thing that the user can do. when ever user click on GUI the next Activity will be start and new GUI set base on coding.<br />
<br />
<b>14. What is Intent?</b><br />
An Intent is exactly what it describes. It's an "intention" to do an action.<br />
<br />
An Intent is basically a message to say you did or want something to happen. Depending on the intent, apps or the OS might be listening for it and will react accordingly.<br />
<br />
There are two types of intents in android:<br />
<br />
<ul style="text-align: left;">
<li>Implicit Intent</li>
<li>Explicit Intent</li>
</ul>
<br />
<b>15. How to Start Another Activity?</b><br />
Intent i = new Intent(getApplicationContext(), Activity2.class); <br />
startActivity(i);<br />
<br />
Note: you need to past this code on onClick method.<br />
<br />
<div style="text-align: center;">
<b style="background-color: white; color: #333333; font-family: verdana, geneva, sans-serif; font-size: 12px; line-height: 19.2px;"><span style="color: #990000;">Also Read:</span> <a href="http://itechaleart.blogspot.com/2014/03/professional-blogging-resources.html" style="color: #999999; text-decoration: none;"><span style="color: #3d85c6;">Professional Blogging Resources for Power Blogging</span></a></b></div>
<br />
<b>16. Explain Folder, File & Description of Android Apps?</b><br />
src: This contains the .java source files for your project.<br />
<br />
gen: contains the .R file, a compiler-generated file that references all the resources found in your project. You should not modify this file.<br />
<br />
bin: contains the Android package files .apk built by the ADT during the build process and everything else needed to run an Android application.<br />
<br />
res/drawable-hdpi<br />
This is a directory for drawable objects that are designed for high-density screens.<br />
<br />
res/layout<br />
This is a directory for files that define your app's user interface.<br />
<br />
res/values<br />
This is a directory for other various XML files that contain a collection of resources, such as strings and colors definitions.<br />
<br />
AndroidManifest.xml<br />
This is the manifest file which describes the fundamental characteristics of the app and defines each of its components.<br />
<br />
<b>17. What is AVD?</b><br />
AVD Stand for Android Virtual Device (emulator), The Android SDK includes a mobile device emulator - a virtual mobile device that runs on your computer.</div>

Top 20 Android Interview Questions And Answers

Android is a mobile operating system (OS) based on the Linux kernel and currently developed by Google. With a user interface based on di...

Android Interview Questions and Answers for Fresher

<div dir="ltr" style="text-align: left;" trbidi="on">
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgxGcY_TXht6z9m-oaPegrbhOK-ZES1ItYwCuEHzg8KAN9WUpf3J95SP-FTO4_QFtg8HhxrSizunBSEq0UJisS6Lg4JdF-cLa84HNs46NBrrO1uVgejl6ro388r_IMfquA_cBVm4QjBhw/s1600/Android+Interview+Ques+&+Ans.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img alt="Android Interview Questions for Fresher " border="0" height="250" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgxGcY_TXht6z9m-oaPegrbhOK-ZES1ItYwCuEHzg8KAN9WUpf3J95SP-FTO4_QFtg8HhxrSizunBSEq0UJisS6Lg4JdF-cLa84HNs46NBrrO1uVgejl6ro388r_IMfquA_cBVm4QjBhw/s1600/Android+Interview+Ques+&+Ans.jpg" width="550" /></a></div>
<div class="separator" style="clear: both; text-align: center;">
<br /></div>
<b></b><br />
<div style="text-align: center;">
<b><b><span style="color: #990000;">Also Read:</span> <a href="http://www.itechaleart.com/2014/04/android-interview-ques-for-experienced.html"><span style="color: #0b5394;">Android interview Questions and Answers for Experienced</span></a></b></b></div>
<b>
</b>
<br />
<div>
<br /></div>
<b>1. What is Android?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">Android is a stack of software for mobile devices which includes an Operating System, middleware and some key applications. The application executes within its own process and its own instance of Dalvik Virtual Machine. Many Virtual Machines run efficiently by a DVM device. DVM executes Java languages byte code which later transforms into .dex format files.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>2. What are the advantages of Android?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">It is simple and powerful SDK.</span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Licensing, Distribution or Development fee is not required.</span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Easy to Import third party Java library.</span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Supporting platforms are – Linux, Mac Os, Windows.</span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Innovative products like the location-aware services, location of a nearby convenience store etc., are some of the additive facilities in Android. </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Components can be reused and replaced by the application framework. </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Optimized DVM for mobile devices. </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">SQLite enables to store the data in a structured manner. </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Supports GSM telephone and Bluetooth, WiFi, 3G and EDGE technologies. </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">The development is a combination of a device emulator, debugging tools, memory profiling and plug-in for Eclipse IDE. </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">The customer will be benefited from wide range of mobile applications to choose, since the monopoly of wireless carriers like AT&T and Orange will be broken by Google Android.</span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></h5>
<b>3. Describe Android Application Architecture.</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">Android Application Architecture has the following components: </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Services – like Network Operation </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Intent - To perform inter-communication between activities or services </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Resource Externalization - such as strings and graphics </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Notification signaling users - light, sound, icon, notification, dialog etc. </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Content Providers - They share data between applications </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">How will you record a phone call in Android? How to get a handle on Audio Stream for a call in Android? </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Permissions.PROCESS_OUTGOING_CALLS: Allows an application to monitor, modify, or abort outgoing calls.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>4. What is <span style="color: #3d85c6;">activity</span>?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">The building block of the user interface is the activity. They're in a long-running conversation with the user and may remain active, even when idle, as long as the conversation continues. In terms of desktop development, an Activity is equivalent to a Form.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>5. Describe the APK format.</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">The (Android Packaging Key) APK file is compressed format of the AndroidManifest.xml file, application code (.dex files), resource files, and other files. A project is compiled into a single .apk file.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>6. What are the different phases of the Activity life cycle?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">As an activity transitions from state to state, it is notified of the change by calls to the following protected methods: </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">1) void onCreate(Bundle savedInstanceState) </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">2) void onStart() </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">3) void onRestart() </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">4) void onResume() </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">5) void onPause() </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">6) void onStop() </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">7) void onDestroy() </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Taken together, these seven methods define the entire lifecycle of an activity.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>7. What is <span style="color: #3d85c6;">intent</span>?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">A class (Intent) describes what a caller desires to do. The caller sends this intent to Android’s intent resolver, which finds the most suitable activity for the intent. E.g. opening a PDF file is an intent, and the Adobe Reader is the suitable activity for this intent.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>8. What is an Explicit Intent?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">In an explicit intent, we actually specify the activity that is required to respond to the intent. In other words, we explicitly designate the target component. This is typically used for application internal messages.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>9. What is an Implicit Intent?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">In an implicit intent, the main power of the android design, we just declare an intent and leave it to the platform to find an activity that can respond to the intent. Here, we do not declare the target component and hence is typically used for activating components of other applications seamlessly</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>10. What is an <span style="color: #3d85c6;">AndroidManifest </span>file?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">Applications declare their components in a manifest file that's bundled into the Android package, the .apk file that also holds the application's code, files, and resources. The manifest is a structured XML file and is always named AndroidManifest.xml for all applications. It is also used for naming any libraries the application needs to be linked against (besides the default Android library) and identifying any permission the application expects to be granted.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>11. What language does Android support for application development?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">Android applications are written using the Java programming language.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>12. What's the difference between a file, a class and an activity in android?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">File - It is a block of arbitrary information, or resource for storing information. It can be of any type. </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Class - Its a compiled form of .Java file . Android finally used this .class files to produce an executable apk </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">Activity - An activity is the equivalent of a Frame/Window in GUI toolkits. It is not a file or a file type it is just a class that can be extended in Android for loading UI elements on view.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>13. What is the significance of the .dex files?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">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.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>14. What does ADT stand for?</b><br />
<h5 style="margin: 5px 2px 2px;">
<span style="background-color: white; color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="background-color: white; font-family: inherit; font-size: small; font-weight: normal;">ADT stands for </span><span style="color: #3d85c6; font-size: small;">Android Development Tools</span><span style="background-color: white; color: #3d85c6; font-family: inherit; font-size: small;"> </span><span style="background-color: white; font-family: inherit; font-size: small; font-weight: normal;">The Android SDK includes several tools and utilities to help you create, test, and debug your projects.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>15. What are the different tools in Android? Explain them?</b><br />
<div>
<b><span style="color: #3d85c6;"><br /></span></b></div>
<div>
<b><span style="color: #3d85c6;">The Android SDK and Virtual Device Manager- </span></b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">It is used to create and manage Android Virtual Devices (AVD) and SDK packages. The AVD hosts an emulator running a particular build of Android, letting you specify the supported SDK version, screen resolution, amount of SD card storage available, and available hardware capabilities (such as touch screens and GPS). </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></h5>
<b><span style="color: #3d85c6;">The Android Emulator- </span></b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">An implementation of the Android virtual machine designed to run within a virtual device on your development computer. Use the emulator to test and debug your Android applications. </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></h5>
<b><span style="color: #3d85c6;">Dalvik Debug Monitoring Service (DDMS) -</span></b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">Use the DDMS perspective to monitor and control the Dalvik virtual machines on which you're debugging your applications. </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></h5>
<span style="color: #3d85c6;"><b>Android Asset Packaging Tool (AAPT) - </b></span><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">Constructs the distributable Android package files (.apk). </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></h5>
<b><span style="color: #3d85c6;">Android Debug Bridge,(adb) -</span></b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">Android Debug Bridge, is a command-line debugging application shipped with the SDK. It provides tools to browse the device, copy tools on the device, and forward ports for debugging.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>16. What is Dalvik Virtual Machine?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">The name of Android's virtual machine. The Dalvik VM is an interpreter-only virtual machine that executes files in the Dalvik Executable (.dex) format, a format that is optimized for efficient storage and memory-mappable execution. The virtual machine is register-based, and it can run classes compiled by a Java language compiler that have been transformed into its native format using the included "dx" tool. The VM runs on top of Posix-compliant operating systems, which it relies on for underlying functionality (such as threading and low level memory management). The Dalvik core class library is intended to provide a familiar development base for those used to programming with Java Standard Edition, but it is geared specifically to the needs of a small mobile device.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>17. What is Android Runtime?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">Android includes a set of core libraries that provides most of the functionality available in the core libraries of the Java programming language. Every Android application runs in its own process, with its own instance of the Dalvik virtual machine. Dalvik has been written so that a device can run multiple VMs efficiently. The Dalvik VM executes files in the Dalvik Executable (.dex) format which is optimized for minimal memory footprint. The VM is register-based, and runs classes compiled by a Java language compiler that have been transformed into the .dex format by the included "dx" tool.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>18. What is the Open Handset Alliance?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">The OHA is a consortium of 84 technology and mobile companies that have joined hands to accelerate innovation in mobile technology and at the same time offer the end users a better, cost-effective and richer mobile experience. Members of this include Google, HTC, Sony, Dell, Intel, Motorola, Qualcomm, Texas Instruments, Samsung, LG, T-Mobile, Nvidia. The OHA was started on 5 November 2007 by Google and 34 other companies. Android is the main software of the alliance.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>19. What is ViewGroup?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">A ViewGroup is a special view that can contain other views (called children.) The view group is the base class for layouts and views containers. This class also defines the class ViewGroup.LayoutParams which serves as the base class for layouts parameters.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>20. What is a <span style="color: #3d85c6;">Service</span>?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">A Service is an application component representing either an application's desire to perform a longer-running operation while not interacting with the user or to supply functionality for other applications to use. Services run without a dedicated GUI, but, like Activities and Broadcast Receivers, they still execute in the main thread of the application's process. A Service could be, facility for an application to expose some of its functionality to other applications.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>21. What is the difference between Service and Thread?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">Service is like an Activity but has no interface. Probably if you want to fetch the weather for example you won't create a blank activity for it, for this you will use a Service. It is also known as Background Service because it performs tasks in background. A Thread is a concurrent unit of execution. You need to know that you cannot update UI from a Thread. You need to use a Handler for this.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>22. What is a Content Provider?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">Content Providers are the only way to share data across Android applications. They store and retrieve data thus making it accessible to all. Content Providers give a uniform interface to access the data. Android platform provides default implementations of content providers for data types like audio, video, images, contact information etc.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>23. What is a Toast Notification?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">A toast notification is a message that pops up on the surface of the window. It only fills the amount of space required for the message and the user's current activity remains visible and interactive. The notification automatically fades in and out, and does not accept interaction events.</span></h5>
<div>
<span style="font-family: inherit; font-size: small; font-weight: normal;"><br /></span></div>
<b>24. What are the other Notifications?</b><br />
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="color: #333333; font-family: Verdana, Geneva, sans-serif; font-size: 12px; line-height: 19.200000762939453px;">--> </span><span style="font-family: inherit; font-size: small; font-weight: normal;">A Status Bar Notification: It is used for persistent reminders that come from the background and request the user's response. </span></h5>
<h5 style="background-color: white; margin: 5px 2px 2px;">
<span style="font-family: inherit; font-size: small; font-weight: normal;">A Dialog Notification: It is Used for Activity-related notifications.</span></h5>
</div>
</div>

Android Interview Questions and Answers for Fresher

Also Read: Android interview Questions and Answers for Experienced 1. What is Android? --> Android is a stack of softwar...