Jawaharlal Nehru Technological University Hyderabad MCA III ANDROID APPLICATION DEVELOPMENT Previous Question Paper (December 2019 - R15)

Android application components are the fundamental building blocks of an Android application. Each component is an entry point through which the system or a user can enter the application. The four primary components are:

• Activities: Represent a single screen with a user interface. An application usually consists of multiple activities that are loosely bound to each other.
• Services: Components that run in the background to perform long-running operations or to perform work for remote processes. They do not provide a user interface.
• Broadcast Receivers: Components that enable the system to deliver events to the app outside of a regular user flow, such as announcing that the screen has turned off or the battery is low.
• Content Providers: Manage a shared set of app data. They allow an application to share data with other applications or manage access to data stored in the file system, an SQLite database, or on the web.

These components are defined in the AndroidManifest.xml file, which provides the system with essential information about the application's structure and requirements.

TableLayout is a ViewGroup in Android that displays child views in rows and columns. It does not display border lines for its rows, columns, or cells. Each row is defined by a TableRow object, which acts as a container for the cells within that row.

Key characteristics and usage include:

• Structure: The TableLayout contains TableRow objects. Each child of a TableRow becomes a cell in that row's column.
• Column Management: Columns can be configured using attributes like android:stretchColumns (to make a column fill available extra space), android:shrinkColumns (to allow a column to shrink if the content is too wide), and android:collapseColumns (to hide specific columns).
• Cell Spanning: While TableLayout does not support row spanning, individual cells can span multiple columns using the android:layout_span attribute on the child view.
• Flexibility: It is useful for creating structured forms or data grids where alignment of labels and input fields is required.

Example structure: