Storing data using the Android SDK
Storing data using the Android SDK
Learn about storing data in Android applications using the tools in the Android SDK.
About the Book
You have a good start on building your Android application, but now comes the time to store the data entered by your users on their device. It's an important part of any application; even a quick prototype needs a way to store data. What is the best way to do it?
Here is a quick guide to get you started with the tools available in the Android SDK, without having to learn yet another new framework or library. You'll learn how to :
- Save simple data to flat files in the internal and external storage of the device,
- Save user preferences using the Preferences API,
- Save structured data in an SQLite database,
- Save images so you can refer to them in a SQLite database,
- Persist the state of an activity so users don't lose their input just because they rotated their device or took a phone call.
This guide also includes examples to help you implement all of those in your own Android applications. Purchase now and you can be up and running in a few minutes!
Table of Contents
- Introduction
-
Chapter 1 : Saving data to a file
- Internal storage
- External storage
- Example code to save to a file
- Chapter 2 : Saving preferences
-
Chapter 3 : Saving to a SQLite database
- Inserting a new row
- Reading existing rows
- Updating existing rows
- Deleting existing rows
- Chapter 4 : Saving an image in a SQLite database
-
Chapter 5 : Storing the state of an activity
- Saving the current UI state
- Saving your data to a permanent data store
- Conclusion
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