How to Replace .withOpacity with .withValues in Your Flutter Codebase

In this blog, learn how to automate repetitive code refactoring in your Dart projects using a simple script. Discover how to identify and update .withOpacity method calls to .withValues across your Flutter codebase efficiently, ensuring consistency and saving development time. Perfect for developers looking to streamline their workflow and maintain cleaner code.

import 'dart:io';

void main() {

final directory = Directory('./lib'); // Update path to your project directory

if (!directory.existsSync()) {

print('Error: Directory not found: ${directory.path}');

return; }

final files = directory .listSync(recursive: true) .whereType() .where((file) => file.path.endsWith('.dart'));

for (var file in files) {

String content = file.readAsStringSync();

// Replace .withOpacity(value) with .withValues(alpha: value)

final updatedContent = content.replaceAllMapped( RegExp(r'.withOpacity(([\d.]+))'), (match) => '.withValues(alpha: ${match[1]})', );

file.writeAsStringSync(updatedContent); print('Updated: ${file.path}'); }

print('Replacement complete!');

}

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TERMINAL RUN: dart lib/main.dart