Data Storage in Flutter - Ultimate Guide

Data storage is an essential part of any application. It helps developers to store and access data easily. In this guide, we will explore the different types of data storage available in Flutter and how to use them.

flutter data storage

What is Data Storage?

Data storage is the process of preserving data in a permanent form. This includes storing data on physical media (such as hard disks, CDs, and DVDs) or in digital form (such as databases, cloud storage, and other online services). It also includes storing data in memory (such as RAM) for quick access.

Why Do We Need Data Storage?

Data storage is important for a number of reasons. It helps us to keep track of data and make it available to users. It also helps to ensure that data is not lost or corrupted. Data storage also helps to optimize the performance of applications by providing quick access to the data.

What are the Different Types of Data Storage?

There are several different types of data storage available in Flutter. Some of the most common types are:

SharedPreferences: SharedPreferences is a key-value store that allows developers to store primitive data types (strings, numbers, booleans, etc.) in a persistent way. It is useful for storing user preferences and settings.
SQLite: SQLite is a powerful relational database system that allows developers to store structured data. It is an open-source library that is available in Flutter.
Realm: Realm is an object-oriented database that allows developers to store and query objects. It is an open-source solution that is available in Flutter.
Secure Storage (Keychain): Secure Storage (Keychain) is a platform-agnostic way to store sensitive data securely. It is available in Flutter as a third-party library.
Disk Storage: Disk Storage is a file-based storage system that allows developers to store data on a physical disk. It is available in Flutter as a third-party library.

Using SharedPreferences in Flutter

SharedPreferences is a key-value store that allows developers to store primitive data types in a persistent way. To use SharedPreferences in Flutter, we need to first import the shared_preferences package.

import 'package:shared_preferences/shared_preferences.dart';

Then, we can use the SharedPreferences class to set and get values from the store. Here is an example of how to set and get a string value in the store:

// Set a string value
SharedPreferences.getInstance().then((prefs) {
  prefs.setString('myKey', 'myValue');
});

// Get a string value
SharedPreferences.getInstance().then((prefs) {
  String myValue = prefs.getString('myKey');
});

For more information, see the SharedPreferences API documentation.

Using SQLite in Flutter

SQLite is a powerful relational database system that allows developers to store structured data. To use SQLite in Flutter, we need to first import the sqflite package.

import 'package:sqflite/sqflite.dart';

Then, we can use the Database class to open and manage a SQLite database. Here is an example of how to open a database and create a table:

// Open a database
Database db = await openDatabase('my_database.db');

// Create a table
await db.execute(
  'CREATE TABLE IF NOT EXISTS myTable (id INTEGER PRIMARY KEY, name TEXT, age INTEGER)',
);

For more information, see the SQLite API documentation.

Using Realm in Flutter

Realm is an object-oriented database that allows developers to store and query objects. To use Realm in Flutter, we need to first import the realm package.

import 'package:realm/realm.dart';

Then, we can use the Realm class to open and manage a Realm database. Here is an example of how to open a database and create a table:

// Open a database
Realm realm = await openRealm('my_database.realm');

// Create a table
await realm.execute(
  'CREATE TABLE IF NOT EXISTS myTable (id INTEGER PRIMARY KEY, name TEXT, age INTEGER)',
);

For more information, see the Realm API documentation.

Secure Storage (Keychain) in Flutter

Secure Storage (Keychain) is a platform-agnostic way to store sensitive data securely. To use Secure Storage in Flutter, we need to first import the flutter_secure_storage package.

import 'package:flutter_secure_storage/flutter_secure_storage.dart';

Then, we can use the FlutterSecureStorage class to set and get values from the store. Here is an example of how to set and get a string value in the store:

// Set a string value
FlutterSecureStorage.write(key: 'myKey', value: 'myValue');

// Get a string value
String myValue = FlutterSecureStorage.read(key: 'myKey');

For more information, see the Secure Storage API documentation.

Disk Storage in Flutter

Disk Storage is a file-based storage system that allows developers to store data on a physical disk. To use Disk Storage in Flutter, we need to first import the path_provider package.

import 'package:path_provider/path_provider.dart';

Then, we can use the PathProvider class to get the application's documents directory. We can then use the dart:io library to create files in this directory. Here is an example of how to create a file in the documents directory:

// Get the documents directory
Directory documentsDirectory = await getApplicationDocumentsDirectory();

// Create a file
File myFile = File('${documentsDirectory.path}/my_file.txt');
await myFile.create();

For more information, see the PathProvider API documentation.

Conclusion

Data storage is an essential part of any application. In this guide, we explored the different types of data storage available in Flutter and how to use them. We looked at SharedPreferences, SQLite, Realm, Secure Storage (Keychain), and Disk Storage. We also provided code examples for each type of storage.

Data Storage in Flutter - Utimate Guide