Persistance

Android

Adding Persistance

• SQL Refresher• Understand how to create and migrate

SQLLite database with android APIs.– Get all tasks– Add a task– Update a task– Delete a task

Task Manager

Cast of Characters• SQLLiteDatabase- an API to a local SQLIte

database file.• SQLLiteOpenHelper – a utility class that make

it easy to create and maintain a local SQLite database.

Refactoring

• Code refactoring is a "disciplined technique for restructuring an existing body of code, altering its internal structure without changing its external behavior“.

• http://en.wikipedia.org/wiki/Code_refactoring

SQLite in Android• SQLite is available on every Android device.

Using an SQLite database in Android does not require any database setup or administration.

• You only have to define the SQL statements for creating and updating the database. Afterwards the database is automatically managed for you by the Android platform.

• More help• http://answers.oreilly.com/topic/1914-what-is-

sqlite/

What is SQLite

• SQLite is an Open Source Database which is embedded into Android. SQLite supports standard relational database features like SQL syntax, transactions and prepared statements. In addition it requires only little memory at runtime (approx. 250 KByte).

• Unlike client–server database management systems, the SQLite engine has no standalone processes with which the application program communicates

Loading Task

Step one

Step One –Loading Tasks

How a SQLLite OpenHelper works

Creating a Database Table

Getting a data from Database

Loading Tasks Steps

Step 2

Adding a task

Adding Tasks

Adding Data to a Database

Step 3

• Updating a task

Step 3-Completing a task

Saving Data to Database

Completing a task

Step 4

• Deleting Task

Step 4-Remove Completed Task

Removing Data from Database

Remove Completed Tasks Steps

• DB desing and implementation.SQLITE DATABASE

APPLICATION

1)Open DB2)Close DB3)Insert and Remove objectsIn a type safe way

DBAdatper ClassThat enbales you to talk to Sqlite database

DBHelper Class

Create TablesUpgrade tables

DBHELPER Class tasks