Скачать или смотреть Updating State with Provider After an API Call in Flutter

Learn how to efficiently update the state with `Provider` in Flutter after making an API call to ensure your frontend reflects data changes immediately.
---
This video is based on the question https://stackoverflow.com/q/66670563/ asked by the user 'GrandMagus' ( https://stackoverflow.com/u/14010121/ ) and on the answer https://stackoverflow.com/a/66670703/ provided by the user 'Steve' ( https://stackoverflow.com/u/9934529/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Updating State with Provider after API call

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Updating State with Provider After an API Call in Flutter

In Flutter development, managing state effectively is crucial for creating responsive applications. One common challenge developers face is how to update the state with Provider after calling an API to update data on the backend (BE). This problem often arises when you need to pass arguments between screens, edit them, and then reflect those changes immediately upon getting the response from the API.

In this guide, we will look at how you can achieve this by updating the state through a Provider after an API call. Let's break it down step by step!

Understanding the Problem

When you execute an API call to update user data and want your UI to reflect the updated information immediately, you might encounter a situation where the UI does not update until you manually refresh the widget. This can lead to a poor user experience.

Scenario Overview

You have a screen to edit user information.

After editing, you call an API to update the backend.

You receive a response with the updated user information.

You want the state of your application to reflect these changes immediately in the UI.

Implementing the Solution

Step 1: Defining the API Call

First, you need to ensure that your API call is set up correctly. You should have a method that sends the data to be updated on the backend and returns the updated user information:

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Updating the State with Provider

Once you receive the updated user data from the API call, the next step is to update the state in your Provider.

First, you should modify your UserStore class by implementing the updateUser method correctly:

[[See Video to Reveal this Text or Code Snippet]]

Here’s what happens within the updateUser method:

Find the index of the user in the clientList that you wish to update.

Replace the old user information with the updated information.

Call notifyListeners() which tells all listening widgets to rebuild with the new state.

Step 3: Using the Provider in Your Widget

In the widget where you perform the API call, make sure to listen to the UserStore provider. When you successfully get a response from the API call, you will update the state like this:

[[See Video to Reveal this Text or Code Snippet]]

Step 4: Ensuring UI Updates

For your UI to update properly, ensure that you are listening to the Provider. Using a Consumer widget or Provider.of<T>(context) will ensure your widget rebuilds whenever the state changes:

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

By following the steps outlined above, you can effectively ensure that your Flutter app updates its state using Provider immediately after an API call to modify data in the backend. This not only improves the user experience by providing real-time updates but also showcases the powerful state management capabilities afforded by the Provider package.

This method represents a clean and responsive approach to managing state in Flutter, making your application both functional and intuitive.

Feel free to leave a comment with any questions or share your experience with state management in Flutter!