Android Training – Lync School

1. Android: Want to start your career as an ​Android​ developer!! Join, ​Lync School​. We provide best ​classroom/Online training​ with Real Time Project experience and expertise faculty guidance. Android is a Linux based operating system. It is an Open Source and is used for mobile devices such as smart phones and tablet computers. It was developed by Open Handset Alliance and led by Google and other companies. Features of Android: Android​ is the powerful operating system which supports best features: ● It is an open source system and is freely available. ● Anyone can personalize the Android platform. ● It provides features like Resizable Widgets, Multi Touch, Multi-Tasking, Media Support etc. ● It supports messaging services like SMS and MMS, Storage, connectivity (Bluetooth, Wi-Fi, GSM, CDMA) etc. Android applications are developed in Java Language using Android software development Kit. Later, they are packed and sold out through Google Play store, Opera Mobile store, F-droid, Amazon App Store and SlideME. Android Architecture: Android​ Architecture id divided into 5 parts. They are: 1. Linux Kernel 2. Native Libraries 3. Android Runtime 4. Application Frame Work 5. Applications 1. Linux Kernel: This is the bottom layer of the Android Architecture. It is responsible for abstraction between Device Drivers and it contains all hardware drivers like Bluetooth, power management, display drivers etc.

2. 2. Native Libraries: Native Libraries is the second layer of Architecture. In this layer, there is Web kit, Open GL, Free Type, SQLite, Media, C runtime library, SSL Libraries responsible for internet etc. 3. Android Run-time: There are core libraries and Dalvik Virtual Machine (DVM) in Android Run-Time to run Android Application. DVM is same as JVM, but it is used in mobile devices. 4. Application Frame work: This layer provides many higher level services to applications in form of Java classes. Android Framework includes User Interface (UI), telephony, resources, locations, data/content Providers and package managers. 5. Applications: This is the top most layer of the ​Android​ Application. Games, contact book, browsers, home etc. comes under Application layer. Components: Application Components are the main building blocks of the android application. They are: ● Activity: It is a class that represents single screen. They help to dictate the UI and handle user interface to smart phone screen. ● View: Anything that is visible by user is a View. For example, Button, Text field etc. ● Intent: Intent is used to start application, Launch an activity, Display web pages, to view list of contacts, to broad cast a message etc. ● Service: A Service is a background processing associated with a application. ● Broadcast Receivers: They act as communication between Android OS and Application. ● Content Provider: They control content (Data) and database Management issues.

3. Android-Drag and Drop: Using ​Android​ drag and drop framework, we can move data from one view to another view using graphical drag and drop gesture. The three important components that supports drag and drop is: 1. Drag event class 2. Drag listeners 3. Helper methods and classes The Drag/Drop​​: There are four steps in drag and drop process: Started​​: This event happens when we start dragging an item in a layout, then the application calls startDrag() Method. When the action started, we use ACTION_DRAG_ STARTED event type. If the action is false, then it will not receive event and the action type is ACTION_DRAG_ENDED. Continuing:​​ This event happens when the user continues drag. The system sends ACTION_DRAG_LOCATION action preceded by ACTION_DRAG_ENTERED action. Dropped: ​​this event happens when the user released the dragged item within the boundary box of a view. The action type used is ACTION_DROP. Ended:​​ after completion of ACTION_DROP event, the system sends the event action ACTION_DRAG_ENDED. Android Activity Life Cycle: This activity managed by 7 methods of ​android​ activity. They are: 1. onCreate 2. onStart : This is called when activity is visible to the user. 3. onResume : This is called when user start interacting. 4. onPause : This is called when activity is not visible to the user. 5. onStop : This is called when activity is no longer visible to user. : This is called when activity is first created

4. 6. onRestart stopped. 7. onDestroy : this is called before the activity is destroyed. : This is called when you restart your activity after you Android Fragments: Android fragment is a sub activity. It is a part of an activity. There may be more than one fragment in an activity. Fragments are embedded in an activity. Each fragment has its life cycle methods. There are 12 life cycle methods. They are: 1. onAttach() 2. onCreate() 3. onCreateView() 4. onActivityCreated() : this is called after the completion of onCreate() method 5. onViewStateRestored() : all the information is provided to fragments. 6. onStart() : this is used when the fragment is visible. 7. onResume() : this is used when the program is interactive. 8. onPause() : this is used when the program is no longer interactive. 9. onStop() : this is called when the fragment is no longer visible. 10.onDestroyViwe() : this allows the fragment to cleanup the resources. 11. onDestroy() : it allows the fragment to do final cleanup of fragment state. 12. onDetach() : this is called before the fragment no longer associates with its activity. : this is called when it is attached to the activity. : this is called when fragment is initialized. : this is used to create and return view hierarchy. The above is the basics of ​Android course. The solid knowledge in the Android makes you start your career as an Android Developer.