Xcode 13.4构建Flutter项目时Command PhaseScriptExecution返回非零退出码问题求助

First off, let's cut to the chase: your build failure isn't caused by standard Flutter/Xcode issues like cached data or generic version mismatches (you've already tried those!). The root problem is a null-safety compatibility conflict between the youtube_player_flutter:8.0.0 package and your current Flutter version.

Looking at your error log:

../../../../flutter/.pub-cache/hosted/pub.dartlang.org/youtube_player_flutter-8.0.0/lib/src/widgets/youtube_player_builder.dart:51:43: Warning: Operand of null-aware operation '?.' has type 'SchedulerBinding' which excludes null.
final physicalSize = SchedulerBinding.instance?.window.physicalSize;

In newer Flutter versions (3.x+), SchedulerBinding.instance is marked as a non-nullable type—meaning it will never be null. The package's code uses the null-aware ?. operator here, which triggers a warning that eventually breaks the Xcode build process.

Here are the most reliable fixes, ordered by preference:

1. Upgrade to a Compatible Version of youtube_player_flutter #

This is the cleanest long-term solution:

• Open your pubspec.yaml file, find the youtube_player_flutter dependency line.
• Replace the version 8.0.0 with the latest stable release (as of now, that's ^9.0.0 or higher).
• Run these commands in your terminal:

  flutter pub upgrade youtube_player_flutter
  flutter clean && flutter pub get
  

• Try rebuilding your project in Xcode.

2. Manually Patch the Package's Source Code (Temporary Fix) #

If you can't upgrade the package right now (e.g., due to project dependencies), you can fix the problematic line directly:

• Navigate to the file path shown in the error: flutter/.pub-cache/hosted/pub.dartlang.org/youtube_player_flutter-8.0.0/lib/src/widgets/youtube_player_builder.dart
• Go to line 51, and remove the null-aware operator ? so the line becomes:

  final physicalSize = SchedulerBinding.instance.window.physicalSize;
  

• Save the file, then run flutter clean && flutter pub get before rebuilding.

3. Align Your Flutter Version with the Package's Requirements #

If you're using Flutter 3.x, youtube_player_flutter:8.0.0 isn't fully compatible. You have two options here:

• Upgrade Flutter: Ensure you're on a stable 3.x release that supports newer package versions.
• Downgrade the package: Look for a version of youtube_player_flutter that's explicitly compatible with your current Flutter version (check the package's changelog for details).

Bonus Troubleshooting Steps #

If the above fixes don't work, double-check these:

• Make sure Xcode has permission to access your project folder: Go to System Preferences > Security & Privacy > Files and Folders, and ensure Xcode is allowed access to your project directory.
• Delete Xcode's Derived Data: Open Xcode, go to File > Project Settings > Derived Data, click the arrow to open the folder, delete all contents, then restart Xcode and rebuild.

内容的提问来源于stack exchange，提问作者Vickey Rajak