Android Interview Questions and Answers Set 4

31.What is the difference between an implicit intent and explicit intent?

There are two types of Intent implicit and explicit intent, let see some more difference between them.

Implicit: Implicit intent is when you call system default intent like send email, send SMS, dial number.

For example,

Intent sendIntent = new Intent();

sendIntent.setAction(Intent.ACTION_SEND);

sendIntent.putExtra(Intent.EXTRA_TEXT, textMessage);

sendIntent.setType(“text/plain”)

startactivity(sendIntent);

Explicit: Explicit intent when you call you’re on application activity from one activity to another

For example, first activity to second activity:

Intent intent = new Intent(first.this, second.class);

startactivity(intent);

32.How can your application perform actions that are provided by other application e.g. sending email?

Intents are created to define an action that we want to perform and launches the appropriate activity from another application.

Intent intent = new Intent(Intent.ACTION_SEND);intent.putExtra(Intent.EXTRA_EMAIL, recipientArray);

startActivity(intent);

33.Name some exceptions in android?

  • Inflate Exception
  • OutOfResourceException
  • BadSurfaceTypeException
  • BadTokenException

34.What is the importance of XML-based layouts?

The Purpose of XML-based layouts provides a consistent and somewhat standard means of setting GUI definition format. Normally, layout details are placed in XML files while other items are placed in source files.

35.What is AVD?

AVD Stand for Android Virtual Device (emulator), The Android SDK includes a mobile device emulator – a virtual mobile device that runs on your computer.

36.Differentiate between LinearLayout, RelativeLayout, AbsoluteLayout.

LinearLayout arranges it’s children in a single row or single column one after the other.

A RelativeLayout arranges it’s children in positions relative to each other or relative to parent depending upon the LayoutParams defined for each view.

AbsoluteLayout needs the exact positions of the x and y coordinates of the view to position it. Though this is deprecated now.

37.Is it okay to change the name of an application after its deployment?

It is not recommended to change the application name after its deployment(final stage) because this action may break some functionality. For example, shortcuts will not work if you change application name.

38.When does Android start and end an application process?

Android starts an application process when application’s component needs to be executed. It then closes the process when it’s no longer needed (garbage collection).

39.What type of listener is used to get the ratings from the RatingBar Widgets?

onRatingBarChangeListener() is used. Click to get more details about RatingBar and SeekBar.

40.What are the features of 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
  • 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.