Android
Android is the mobile operating system which is designed by the Google based on the Linux kernel. This designed primarily for the touch screen mobiles. The user interface is mainly based on direct manipulation touch gestures which are corresponded to real-world actions such as swiping, tapping and pinching to manipulate the on-screen objects along with virtual keyboard for text input. Android Training in Chennai offers the well trained MNC professionals as trainers.
Components of Android
The application components are the essential building blocks for Android applications. These components are coupled by the application manifest file Android Manifest.xml file.
There are four main important components that can be used with android application are:
1. Activities
This represents the single screen with user interface in short Activity performs actions on the screen. Let us take an example of email application which has the single activity; it shows the list of new emails, another activity is to compose the email and other for reading the emails.
Activity can be represented as the Sub Class of an activity as follows
Public class MainActivity extends Activity {
}
2. Broadcast Receivers
Broadcast Receivers has respond to broadcast messages from other applications or from the other system. This applications can also initiate the broadcasts to other applications know the some data has been downloaded to the device and available for them. Android Course in Chennai is the best place to learn this course. So this is the broadcast receiver who will intercept this communication and this will initiate the appropriate action.
Every message is broadcaster as Intent Object by implementing as a subclass of Broadcast Receiver.
public class MyReceiver extends BroadcastReceiver {
public void onReceive (context,intent) {}
}
3. Services
This is a component which runs in the background to perform long running operations in the system. If the service might play music in the background while the user is in a different application. It fetches the data over the network without blocking the user interaction with an activity.
This is implemented by the Subclass of Service class as follows
public class MyService extend Service {
}
4. Content Providers
A content provider component supplies the data from one application to others on request. These base requests are handled by the methods of the Content Resolver Class. The data can be stored in the file system, the data somewhere entirely. Android Training at FITA is the best training institute in Chennai for this course. This is implemented as Subclass of Content Provider class and must implement standard set of APIs which enable other applications to perform transactions.
public class MyContentProvider extends ContentProvider {
public void oncreate () {}
Additional Components
1. Fragments
This represents the portion of user interface in the activity.
2. Views
The UI elements that are drawn on screen including buttons, list forms etc.
3. Layouts
The view hierarchies which control screen format and appearance of the views.
4. Resources
External elements such as strings, constants and drawable pictures.
5. Intents
The messages are wired together. These messages are together wired to sent the system.