Скачать или смотреть Solving the Problem of Disappearing Label Text in Flutter Forms

Learn how to fix the issue of disappearing label text and button logic in Flutter forms with practical solutions and examples.
---
This video is based on the question https://stackoverflow.com/q/64218725/ asked by the user 'Flari' ( https://stackoverflow.com/u/10105454/ ) and on the answer https://stackoverflow.com/a/64218881/ provided by the user 'John Joe' ( https://stackoverflow.com/u/5156075/ ) 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: Flutter why is the label text disappearing

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.
---
Why is the Label Text Disappearing in Flutter Forms?

If you are a Flutter developer and have encountered the frustrating problem of label text disappearing in your form fields, you’re not alone. This common issue arises when users interact with text fields in a way that modifies the appearance of your application's user interface. Many developers, including beginners, find themselves puzzled by this scenario. In this guide, we will explore the problem and provide a comprehensive solution to ensure your label text displays correctly.

The Problem Explained

Imagine you have a Flutter app with a form that includes fields for users' names and surnames. These fields ideally have placeholder text that transforms into labels when the user begins typing. However, there are instances where the label text disappears entirely or does not function as expected when input is provided. Additionally, the button meant to proceed to the next step may enable incorrectly due to input validation logic issues.

Issues Identified

Disappearing Label Text: The label text isn't visible when it should be after user input.

Button Logic Flaw: The button enabling behaves like an "Or" logic instead of "And," meaning it allows the button to activate even when only one of the fields is filled out.

Solution: Using TextEditingController

To avoid these issues, we recommend using the TextEditingController with your TextField widgets. This controller provides a more robust way of managing the state of the input fields.

Step 1: Initialize the Controllers

Start by declaring instances of TextEditingController for both the name and surname fields. This initialization will allow you to manage the input text more effectively.

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

Step 2: Use the Controllers in TextFields

Integrate the controllers in your TextField widgets. This substitution ensures that the label text reflects accurately based on the current text input.

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

Repeat this for your surname field, replacing the corresponding variables with _inputSurnameController.

Step 3: Update Button Logic

Now that your inputs are correctly controlled, you need to revise the button logic to ensure it behaves as an "And" logic. Here’s an example of how you can handle the button state based on both fields:

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

Conclusion

By implementing TextEditingController for your text fields and refining your button's enabling logic, you will not only mitigate the issue of disappearing labels but also enhance the overall user experience of your Flutter application. This approach allows for a cleaner, more reliable method to manage your form inputs and ensures that your buttons only become active under the intended conditions.

With these adjustments, you are well on your way to creating a functional and visually appealing Flutter form!