How To Save Settings Locally On React Native App

React Native is a popular framework for developing mobile applications that are both efficient and user-friendly. When building a mobile app, it’s essential to save certain settings locally so that users can access them without having to re-enter them every time they use the application. In this article, we’ll discuss how to save settings locally on a React Native app.

1. Understand Local Storage in React Native.

1. Local storage is a way for developers to store small amounts of data within the user’s browser or mobile device.
2. This data can be accessed quickly by the application, making it an ideal option for storing small user-specific settings.
3. In React Native, local storage is available through the AsyncStorage library.
4. AsyncStorage provides a simple key-value store that can be used to save and retrieve data from the device’s file system.

2. Import AsyncStorage.

1. Before you can start using AsyncStorage, you need to import it into your project.
2. You can do this by adding the following code at the top of your file.

   ```
   import { AsyncStorage } from 'react-native';
   ```

3. Save the Settings.

1. Once you’ve imported AsyncStorage into your project, you can begin saving your settings.
2. To do this, you’ll need to create a function that will be responsible for saving settings.
3. Here is an example of how to save the setting.
   

   ```
   async saveSetting(settingName, settingValue) {
       try {
           await AsyncStorage.setItem(settingName, JSON.stringify(settingValue));
       } catch (error) {
           console.log(error);
       }
   }
   ```

4. The above code saves a setting with the name `settingName` and value `settingValue`.
5. The `setItem` method is used to save the setting, and the `JSON.stringify` method is used to convert the value to a string.

4. Retrieve the Settings.

1. After saving the settings, you can retrieve them using the `getItem` method.

   ```
   async getSetting(settingName) {
       try {
           const value = await AsyncStorage.getItem(settingName);
           if (value !== null) {
               return JSON.parse(value);
           }
       } catch (error) {
           console.log(error);
       }
   }
   ```

2. The above code retrieves a setting with the name `settingName` and returns its parsed value.

5. Implement Settings in Your App.

1. Now that you have saved and retrieved your settings, you can use them in your application.
2. Suppose you have a setting for the user’s preferred language.
3. You can implement this setting by retrieving the user’s prefered language from local storage when the app loads, and then using it to set the language of the app.
4. Here is an example.
   

   ```
   async componentDidMount() {
       const userLanguage = await this.getSetting('language');
       if (userLanguage) {
           // Set the language of the app
           i18n.locale = userLanguage;
       }
   }
   ```

5. In the above code, the `componentDidMount` method is used to retrieve the `language` setting from local storage.
6. If the setting exists, it sets the language of the app using the i18n library.

6. Conclusion.

1. Saving settings locally on a React Native app is essential for providing a smooth user experience.
2. By using the AsyncStorage library, you can easily store and retrieve small amounts of data from the device’s file system.
3. Following the steps outlined in this article, you can implement local storage for your mobile application and provide a more personalized experience for your users.