Скачать или смотреть How to Return Data from a Second Screen in Flutter

Learn how to effectively return data from a second screen in Flutter using the Navigator method, simplifying your navigation and data transfer processes in mobile applications.
---
This video is based on the question https://stackoverflow.com/q/74801962/ asked by the user 'Happy' ( https://stackoverflow.com/u/17006711/ ) and on the answer https://stackoverflow.com/a/74801992/ provided by the user 'eamirho3ein' ( https://stackoverflow.com/u/10306997/ ) 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: Return data from a screen

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.
---
Understanding Screen Navigation in Flutter

Navigating between screens in a Flutter application is a common requirement. Often, you may need to not only navigate to a new screen but also return some data back to the previous one. This is a common scenario when you're working with two screens and want to pass a value back from the second screen to the first.

In this guide, we'll explore how to achieve this in a structured and easy-to-understand manner. Imagine you have two screens: the first screen, where users initiate an action that leads to the second screen, and then your goal is to return a number from the second screen back to the first.

The Problem: Returning Data from the Second Screen

You have two screens in your Flutter app, and you want a specific number returned from the second screen once the user has completed their actions there. Your challenge is to figure out how to set up proper navigation and handle the returned data on the first screen.

In your initial query, you mentioned the use of Navigator.pop(context, number), which is how we can send data back from the second screen. However, the question then arises: how do we handle this returned data on the first screen?

The Solution: Setting Up the Navigator

To return data from the second screen, we will use Flutter's Navigator class. Here's how to do it step by step:

Step 1: Navigating to the Second Screen

You need to push to the second screen using Navigator.push, while also preparing to receive the data back. Here's an example code snippet to accomplish this:

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

Explanation of the Code

onPressed: This is an event that triggers when a user taps a button.

await Navigator.of(context).push(...): This line opens your NewScreen() and waits for it to complete. The await keyword enables you to pause the execution of your method until the new screen is popped and returns data back.

if (result != null): After the second screen is dismissed, you check if there's any result coming back. If there is, you can use it as needed.

Step 2: Returning Data from the Second Screen

On the second screen, when you're ready to send data back to the first screen, you'll use Navigator.pop. Here’s how it can look:

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

Where number is the value you want to pass back.

Example Scenario

Imagine your second screen is where you ask for user input, such as a rating or a score. Once the user submits their input, you use Navigator.pop to return that input back to the first screen.

This creates a smooth flow of data and allows your application to remain responsive and user-friendly.

Conclusion

Returning data from one screen back to another in Flutter is straightforward. By effectively using the Navigator class and handling data with await, you can create interactive experiences that feel seamless to users.

Always remember to check for null values when processing returned data to avoid any unexpected errors. So, whether you're building a product application, a game, or any other type of app, this navigation technique will be invaluable.

By applying these methods, you can ensure that your Flutter applications are not only functional but also provide a great user experience!