Скачать или смотреть How to Update Data from Firebase in Your Flutter App

Learn how to efficiently update data from Firebase in Flutter using StreamBuilder to retrieve live data updates.
---
This video is based on the question https://stackoverflow.com/q/71069433/ asked by the user 'mberker0' ( https://stackoverflow.com/u/18154892/ ) and on the answer https://stackoverflow.com/a/71070784/ provided by the user 'BJW' ( https://stackoverflow.com/u/9424323/ ) 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: How can I update the data that received from firebase

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.
---
How to Update Data from Firebase in Your Flutter App

In today's fast-paced app development world, users expect real-time updates. If you're building an application using Flutter and Firebase, you might find yourself facing the challenge of how to constantly update data from Firebase. You might encounter a situation where your app only fetches data when it is opened, but you want it to refresh every few minutes or so. This guide will guide you on how to implement live updates using Firebase in Flutter.

The Problem

Imagine you have a function in your Flutter app that retrieves data from your Firebase Realtime Database. Here’s the basic structure of what that function might look like:

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

This function works perfectly fine for initially fetching data. However, if you need to keep the data updated in real-time, calling ref.once() is not sufficient as it only retrieves the data once and does not listen for any changes.

How to Make It Dynamic

To achieve dynamic updates, you need to embrace the power of StreamBuilder. This widget allows you to listen for changes to a given data source, in this case, your Firebase database.

The Solution: Using StreamBuilder

StreamBuilder Basics

The StreamBuilder widget listens to a stream and builds itself based on the latest snapshot of interaction with that stream. In this case, you can listen to the Firebase database reference, which will automatically update the UI whenever there’s a change.

Implementing StreamBuilder

Here’s how you can implement the StreamBuilder to fetch data from Firebase continuously:

Set Up Firebase Reference: Start by creating a reference to the data you want to listen to.

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

Use StreamBuilder in Your UI: Replace the FutureBuilder with a StreamBuilder to continually listen for updates from Firebase.

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

Breakdown of the Code

Stream: The key here is ref.onValue, which streams data updates whenever the value at the specified node changes.

Builder: Inside the builder, you can handle different connection states. If the connection is waiting, display a loading spinner (CircularProgressIndicator).

Data Handling: Once the data is available, you can format and display it as desired.

Conclusion

By using a StreamBuilder, your Flutter app can efficiently update data received from Firebase in real-time. This way, you're no longer limited to fetching data just once at app startup; instead, your application can respond instantly to updates in the Firebase Realtime Database.

By following the steps outlined in this guide, you are now equipped to implement dynamic data updates in your Flutter application, enhancing user experience and functionality.

Stay tuned for more insights and guidance on Flutter and Firebase development!