Скачать или смотреть How to Hide BottomNavigationBar in Flutter When Keyboard is Open

Discover how to effectively manage your Flutter app's `bottomNavigationBar` visibility when the keyboard is displayed. Learn simple solutions to enhance user experience!
---
This video is based on the question https://stackoverflow.com/q/76385675/ asked by the user 'Jules LT' ( https://stackoverflow.com/u/22003232/ ) and on the answer https://stackoverflow.com/a/76386685/ provided by the user 'Roman Maydana' ( https://stackoverflow.com/u/21990317/ ) 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 to hide bottomNavigationBar when keyboard is used?

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 Hide BottomNavigationBar in Flutter When Keyboard is Open

When developing Flutter applications, you might encounter scenarios where you want to streamline user interactions, especially when dealing with input fields. A common issue many developers face is managing the visibility of the bottomNavigationBar when the keyboard is shown. In this guide, we’ll explore effective solutions to this problem and ensure a better user experience in your Flutter app.

Understanding the Problem

In a typical Flutter application, developers often use a bottomNavigationBar to navigate between different screens or functionalities. However, when the on-screen keyboard appears (for example, when a user taps on a TextField), the bottomNavigationBar may still occupy space at the bottom. This can lead to an obstructed view and a frustrating user experience.

Example Scenario

Consider you have implemented a bottomNavigationBar using a package like GNav for better navigation. Despite setting resizeToAvoidBottomInset: false in the Scaffold, the bottomNavigationBar remains visible when the keyboard is open, causing layout issues. Here’s a snippet of this scenario:

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

You want to ensure that the bottomNavigationBar is hidden once the keyboard appears to maintain a clean interface.

Solution: Using WidgetsBindingObserver

To effectively hide the bottomNavigationBar when the keyboard is open, we can utilize the WidgetsBindingObserver. This allows us to listen for changes in the application’s lifecycle, including keyboard visibility.

Step-by-Step Implementation

Here’s how you can implement this functionality:

Create a Stateful Widget:
Start by defining a stateful widget that will manage the keyboard visibility.

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

Add WidgetsBindingObserver:
Implement the WidgetsBindingObserver to detect changes related to keyboard visibility.

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

Override Lifecycle Methods:
Use initState and dispose to register and deregister the observer.

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

Detect Keyboard Visibility:
Implement the didChangeMetrics method to detect when the keyboard appears.

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

Build UI with Conditional Logic:
Render your bottomNavigationBar conditionally based on the keyboard visibility.

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

Conclusion

By following these steps, you can seamlessly hide the bottomNavigationBar when the keyboard is displayed, thereby improving the overall user experience of your Flutter application. This not only makes your app look more polished but also allows users to focus on their input without obstruction.

Feel free to experiment with these solutions and enhance your Flutter projects further! If you have any questions or need further assistance, don't hesitate to ask.