1. What is android?
A.Android is a stack of software for mobile devices
which has 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 language byte code which later transforms into .dex format files.
2. What are the advantages
of Android?
A. The following are the advantages of Android:
* 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.
* Features like weather details, live RSS feeds, opening screen, icon on the
opening screen can be customized * Innovative products like the location-aware
services, location of a nearby convenience store etc., are some of the additive
facilities in Android. Components can be reused and replaced by the application
framework. * Optimized DVM for mobile devices * SQLite enables to store the
data in a structured manner. * Supports GSM telephone and Bluetooth, WiFi, 3G
and EDGE technologies * The development is a combination of a device emulator,
debugging tools, memory profiling and plug-in for Eclipse IDE.
3. Explain about the
exceptions of Android?
A.The following are the exceptions that are supported by
Android * InflateException : When an error conditions are occurred, this
exception is thrown * Surface.OutOfResourceException: When a surface is not
created or resized, this exception is thrown *
SurfaceHolder.BadSurfaceTypeException: This exception is thrown from the
lockCanvas() method, when invoked on a Surface whose is
SURFACE_TYPE_PUSH_BUFFERS * WindowManager.BadTokenException: This exception is
thrown at the time of trying to add view an invalid
WindowManager.LayoutParamstoken.
4. Describe the APK format.
A.The APK file is compressed the AndroidManifest.xml
file, application code (.dex files), resource files, and other files. A project
is compiled into a single .apk file.
5. What is .apk extension?
A.The extension for an
Android package file, which typically contains all of the files related to a
single Android application. The file itself is a compressed collection of an
AndroidManifest.xml file, application code (.dex files), resource files, and
other files. A project is compiled into a single .apk file.
6. What is .dex extension?
A.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.
7. Explain the Architecture
of Android ?
A. Top -> Applications (Contacts, Browser, Phone, etc)
Below Applications ->
Application Framework(Activity Manager, Window Manager, Content Providers, View
System, Package manager,
Telephony manager, Resource,
Notification, Location managers)
Below Application Framework
-> System Libraries(Like Sqlite, webkit, SSL, OpenGL, Media Framework etc)
& Android Runtime( Core Libraries and DVM).
Atlast Last -> Linux Kernel
(which composed of drivers like display, camera etc.)
10. What is an activity?
A. A single screen in an application, with supporting
Java code.
An activity presents a visual
user interface for one focused endeavor the user can undertake.
For example, an activity might
present a list of menu items users can choose from or it might display
photographs along with their captions.
11. What is a service?
A.A service doesn’t have a visual user interface, but
rather runs in the background for an indefinite period of time.
For example,
a service might play background music as the user attends to other matters, or
it might fetch data over the network or calculate something and provide the
result to activities that need it.Each service extends the Service base class.
