Скачать или смотреть How to Get Input Value from a Stateful Widget in Flutter

Learn how to effectively retrieve input values from a custom Stateful Widget in Flutter, enhancing your app's performance and user experience!
---
This video is based on the question https://stackoverflow.com/q/76519860/ asked by the user 'Ken' ( https://stackoverflow.com/u/16362581/ ) and on the answer https://stackoverflow.com/a/76520260/ provided by the user 'Sujan Gainju' ( https://stackoverflow.com/u/4639894/ ) 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: Get value from a Stateful Widget

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 Get Input Value from a Stateful Widget in Flutter

When developing applications with Flutter, you often need to create custom forms to capture user input. One common hurdle developers face is accessing the values from a custom TextFormField when it's extracted into a Stateful Widget. In this guide, we will explore a practical solution for this problem.

The Challenge: Accessing Controller Values in Stateful Widgets

You've created a CustomTextFormField widget for user input, like a username or phone number, and it’s encapsulated within a Stateful Widget. However, you need access to the _controller.text from the parent widget to store the user data, possibly in local storage using packages like shared_preferences. Here’s a brief look at the key custom structures we will discuss:

CustomTextFormField - Holds user input, such as username and phone number.

RegisterPage - Takes user input and provides functionality for registration.

Why Not Declare the Controller inside the Widget?

The simplest approach might seem to declare the TextEditingController directly within the CustomTextFormField. However, this makes it challenging for the parent widget to access the text input. Instead, a more effective method is to pass the controller as a parameter from the parent widget.

The Solution: Passing the TextEditingController

Step 1: Modify the CustomTextFormField

To enable access to the TextEditingController outside the CustomTextFormField, you need to pass the controller as a parameter. Here's how you can do it:

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

Step 2: Update the RegisterPage

Next, define controllers for the user input fields at the RegisterPage level and pass these controllers to the CustomTextFormField instances:

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

Conclusion

By modifying your CustomTextFormField widget to accept a TextEditingController passed down from the parent widget, you can easily access input values and ensure efficient management of user data. This approach not only enhances performance but also makes your code cleaner and more maintainable.

Now you can confidently create more complex forms in your Flutter applications! Happy coding!