The document discusses various storage options for persistent data in Android applications including Shared Preferences for key-value pairs, internal storage for private device memory, external storage for public shared storage, and SQLite databases for structured private data. It also covers topics like Google Maps API keys, location providers, and using the device camera. The document provides code examples for reading and writing to each of these storage types and accessing location services.

1. Android
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2. Storage Options
Android provides several options for you to save
persistent application data.
Shared Preferences - Store private primitive
data in key-value pairs.
Internal Storage - Store private data on the
device memory.
External Storage - Store public data on the
shared external storage.
SQLite Databases - Store structured data in a
private database.

3. SharedPreferences - getSharedPreferences() - Use this if you need
multiple preferences files identified by name,
which you specify with the first parameter.
- getPreferences() - Use this if you need only
one preferences file for your Activity.
To read values, use SharedPreferences
methods such as getBoolean() and getString().
To write values:
1. Call edit() to get a SharedPreferences.Editor.
2. Add values with methods such as putString().
3. Commit the new values with commit()

4. Internal Storage To create and write a private file to the internal
storage:
1. Call openFileOutput() with the name of the file
and the operating mode. This returns a
FileOutputStream.
2. Write to the file with write().
3. Close the stream with close().

5. External Storage If you're using API Level 7 or lower, use
getExternalStorageDirectory() to open a File that represents the
root of the external storage, then save your shared files in one of
the following directories:
Music/ - Media scanner classifies all media found here as user
music.
Podcasts/ - Media scanner classifies all media found here as a
podcast.
Ringtones/ - Media scanner classifies all media found here as a
ringtone.
Alarms/ - Media scanner classifies all media found here as an
alarm sound.
Notifications/ - Media scanner classifies all media found here as
a notification sound.
Pictures/ - All photos (excluding those taken with the camera).
Movies/ - All movies (excluding those taken with the camcorder).
Download/ - Miscellaneous downloads.

6. Databases Android provides full support for SQLite
databases. Any databases you create will be
accessible by name to any class in the
application, but not outside the application.
The recommended method to create a new
SQLite database is to create a subclass of
SQLiteOpenHelper and override the onCreate()
method, in which you can execute a SQLite
command to create tables in the database.

7. Databases You can then get an instance of your
SQLiteOpenHelper implementation using the
constructor you've defined. To write to and
read from the database, call
getWritableDatabase() and
getReadableDatabase(), respectively.
These both return a SQLiteDatabase object
that represents the database and provides
methods for SQLite operations.

8. GPS GPS_PROVIDER
This provider determines location using satellites.
Depending on conditions, this provider may take
a while to return a location fix.
NETWORK_PROVIDER
This provider determines location based on
availability of cell tower and WiFi access points.
Results are retrieved by means of a network
lookup.
PASSIVE_PROVIDER
A special location provider for receiving locations
without actually initiating a location fix.

9. Google Maps
The Google Maps Android API v2 uses a new
system of managing keys. Existing keys from a
Google Maps Android v1 application, commonly
known as MapView, will not work with the v2 API.
To access the Google Maps servers with the
Maps API, you have to add a Maps API key to
your application. The key is free, you can use it
with any of your applications that call the Maps
API, and it supports an unlimited number of
users.

10. Google Maps
An Android application that uses the Google
Maps Android API needs to specify the
following settings in its manifest file,
AndroidManifest.xml:
Permissions that give the application access
to Android system features and to the
Google Maps servers.
Notification that the application requires
OpenGL ES version 2.
The Maps API key for the application. The
key confirms that you've registered with the
Google Maps service via the Google APIs
Console.

11. Camera

12. Q&A
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