Flutter 'File.create' Method Argument Mismatch Error

Problem

When running a Flutter project, you might encounter this error:

../../../.pub-cache/hosted/pub.dev/file-6.1.2/lib/src/interface/file.dart:15:16: 
Error: The method 'File.create' has fewer named arguments than those of overridden method 'File.create'. 
Future create({bool recursive = false});

This occurs when there's a version mismatch between your project's dependencies and Flutter's requirements. The file package (version 6.1.2 in this case) doesn't match the interface expected by other SDK components, specifically regarding the File.create method's arguments.

Common Symptoms

• Errors appear after Flutter SDK upgrade
• flutter clean and flutter upgrade don't resolve the issue
• Using outdated or conflicting dependency versions

Recommended Solutions

1. Upgrade Dependencies

First try upgrading all dependencies:

flutter clean
flutter pub upgrade

If this fails, use Dart's package manager:

dart pub upgrade

2. Explicitly Add File Dependency

Add the latest file package to pubspec.yaml:

dependencies:
  file: ^6.1.4

Then refresh dependencies:

flutter pub get

3. Reset Dependency Lock

Delete the lock file and regenerate dependencies:

rm pubspec.lock
flutter pub get

Solution Comparison

Recommended Workflow

# 1. Clean project
flutter clean

# 2. Upgrade dependencies
flutter pub upgrade

# 3. If error persists, add explicit dependency
#    Add 'file: ^6.1.4' to pubspec.yaml then:
flutter pub get

Alternative Workflow

# 1. Remove lock file
rm pubspec.lock

# 2. Clean and refresh
flutter clean
flutter pub get

# 3. Use Dart package manager if needed
dart pub upgrade

Explanation

Why This Error Occurs

1. Transitive Dependency Conflict:

   • Packages in your project depend on different file package versions
   • Older versions (like 6.1.2) have incompatible method signatures

2. Dart SDK Mismatch:

   • Your project uses Dart version different from Flutter SDK's Dart
   • Version constraints aren't properly resolved

3. Stale Build Artifacts:

   • Previous build artifacts reference outdated interface implementations

Why These Solutions Work

• Dependency Upgrade: Forces resolution to latest compatible versions
• Explicit file Dependency: Overrides transitive dependency versions
• Lock File Reset: Clears outdated version constraints locking incompatible dependencies
• Flutter Clean: Removes cached build artifacts causing conflicts

Prevention Tips

1. Regularly run flutter pub outdated to check for updates
2. Keep Flutter on stable channel (flutter channel stable)
3. Review dependency tree with flutter pub deps
4. Specify exact versions for critical packages in pubspec.yaml

When Solutions Don't Apply

If you still encounter issues:

1. Check Flutter Channel: Ensure you're not on unstable builds

   flutter channel stable
   flutter upgrade

2. Verify Dependency Constraints:

   • Ensure no packages force old file versions
   • Look for dependency_overrides in pubspec.yaml

3. Inspect Gradle/Kotlin Versions (Android only):

   • Update android/build.gradle:

     ext.kotlin_version = '1.8.20' // Use latest stable

4. Check Firebase Dependencies:

   classpath 'com.google.gms:google-services:4.3.15'

Additional Information

This error stems from a known Flutter GitHub issue related to the file package API changes after version 6.1.3. The solutions provided focus on updating the dependency resolver to select compatible packages while removing version conflict artifacts.

Why Explicit Dependency Works

Adding file: ^6.1.4 explicitly:

1. Overrides transitive dependencies by forcing version resolution
2. Ensures interface compatibility with Flutter SDK
3. Addresses the core API mismatch in method signatures

Implementing these structured solutions resolves the File.create method argument mismatch in most scenarios while promoting dependency management best practices.