Error: dart library ‘dart:ui’ is not available on this platform.

Query: error: dart library ‘dart:ui’ is not available on this platform.

Answer:

When you encounter the error message “dart library ‘dart:ui’ is not available on this platform,” it typically means that you are trying to run a Dart code that relies on the Flutter framework on a platform that does not support Flutter.

The ‘dart:ui’ library is an integral part of the Flutter framework and provides the necessary APIs for rendering the user interface. It is not compatible with platforms that do not support Flutter, such as web browsers or Node.js.

To resolve this issue, you have a few options:

1. Running on Flutter-supported platforms: Ensure that you are running your Dart/Flutter code on platforms supported by Flutter. Flutter is primarily designed for creating native mobile applications for iOS and Android. You can use an emulator (such as Android Emulator) or a physical device to run your code.
2. Using Flutter for web (Technical Preview): Starting from Flutter 1.12, Flutter for web has been available in technical preview. This allows you to write Flutter code that can be compiled to run on web browsers. To enable Flutter for web, you need to switch to the ‘dev’ channel and run the following command:
   flutter channel dev
flutter upgrade
flutter config --enable-web
   Once enabled, you should be able to run Flutter apps on web browsers using the flutter run -d chrome command.

Here’s an example of how a Flutter code might produce the mentioned error:

// Importing dart:ui, which is only available on Flutter-supported platforms, will cause the error
import 'dart:ui';

void main() {
  print('Hello, Flutter!');
}

In the above example, importing the ‘dart:ui’ library will cause the error when you attempt to run it on a platform that doesn’t support Flutter (e.g., web browser or Node.js).

It’s important to choose the appropriate platform for running Flutter-based Dart code to avoid this error.