我成功在iOS设备上运行了基本的flutter示例。我有最后一个Xcode和Catalina。但是每次我尝试添加软件包时，都会遇到类似的问题：
Running pod install...
CocoaPods' output:
↳
Preparing
Analyzing dependencies
Inspecting targets to integrate
Using `ARCHS` setting to build architectures of target `Pods-Runner`: (``)
Fetching external sources
-> Fetching podspec for `Flutter` from `Flutter`
-> Fetching podspec for `screenshot_share_image` from `.symlinks/plugins/screenshot_share_image/ios`
Resolving dependencies of `Podfile`
CDN: trunk Relative path: CocoaPods-version.yml exists! Returning local because checking is only perfomed in repo update
Comparing resolved specification to the sandbox manifest
A Flutter
A screenshot_share_image
Downloading dependencies
-> Installing Flutter (1.0.0)
-> Installing screenshot_share_image (0.0.1)
- Running pre install hooks
CDN: trunk Relative path: CocoaPods-version.yml exists! Returning local because checking is only perfomed in repo update
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### Command
```
/usr/local/bin/pod install --verbose
```
### Report
* What did you do?
* What did you expect to happen?
* What happened instead?
### Stack
```
CocoaPods : 1.9.3
Ruby : ruby 2.6.3p62 (2019-04-16 revision 67580) [universal.x86_64-darwin19]
RubyGems : 3.0.3
Host : Mac OS X 10.15.5 (19F101)
Xcode : 11.5 (11E608c)
Git : git version 2.24.3 (Apple Git-128)
Ruby lib dir : /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib
Repositories : master - git - https://github.com/CocoaPods/Specs.git @ 1e10b07eb1af53011a1e344b101c47327c5f8b62
trunk - CDN - https://cdn.cocoapods.org/
```
### Plugins
```
cocoapods-deintegrate : 1.0.4
cocoapods-plugins : 1.0.0
cocoapods-search : 1.0.0
cocoapods-stats : 1.1.0
cocoapods-trunk : 1.5.0
cocoapods-try : 1.2.0
```
### Podfile
```ruby
# Uncomment this line to define a global platform for your project
# platform :ios, '9.0'
# CocoaPods analytics sends network stats synchronously affecting flutter build latency.
ENV['COCOAPODS_DISABLE_STATS'] = 'true'
project 'Runner', {
'Debug' => :debug,
'Profile' => :release,
'Release' => :release,
}
def parse_KV_file(file, separator='=')
file_abs_path = File.expand_path(file)
if !File.exists? file_abs_path
return [];
end
generated_key_values = {}
skip_line_start_symbols = ["#", "/"]
File.foreach(file_abs_path) do |line|
next if skip_line_start_symbols.any? { |symbol| line =~ /^\s*#{symbol}/ }
plugin = line.split(pattern=separator)
if plugin.length == 2
podname = plugin[0].strip()
path = plugin[1].strip()
podpath = File.expand_path("#{path}", file_abs_path)
generated_key_values[podname] = podpath
else
puts "Invalid plugin specification: #{line}"
end
end
generated_key_values
end
target 'Runner' do
use_frameworks!
use_modular_headers!
# Flutter Pod
copied_flutter_dir = File.join(__dir__, 'Flutter')
copied_framework_path = File.join(copied_flutter_dir, 'Flutter.framework')
copied_podspec_path = File.join(copied_flutter_dir, 'Flutter.podspec')
unless File.exist?(copied_framework_path) && File.exist?(copied_podspec_path)
# Copy Flutter.framework and Flutter.podspec to Flutter/ to have something to link against if the xcode backend script has not run yet.
# That script will copy the correct debug/profile/release version of the framework based on the currently selected Xcode configuration.
# CocoaPods will not embed the framework on pod install (before any build phases can generate) if the dylib does not exist.
generated_xcode_build_settings_path = File.join(copied_flutter_dir, 'Generated.xcconfig')
unless File.exist?(generated_xcode_build_settings_path)
raise "Generated.xcconfig must exist. If you're running pod install manually, make sure flutter pub get is executed first"
end
generated_xcode_build_settings = parse_KV_file(generated_xcode_build_settings_path)
cached_framework_dir = generated_xcode_build_settings['FLUTTER_FRAMEWORK_DIR'];
unless File.exist?(copied_framework_path)
FileUtils.cp_r(File.join(cached_framework_dir, 'Flutter.framework'), copied_flutter_dir)
end
unless File.exist?(copied_podspec_path)
FileUtils.cp(File.join(cached_framework_dir, 'Flutter.podspec'), copied_flutter_dir)
end
end
# Keep pod path relative so it can be checked into Podfile.lock.
pod 'Flutter', :path => 'Flutter'
# Plugin Pods
# Prepare symlinks folder. We use symlinks to avoid having Podfile.lock
# referring to absolute paths on developers' machines.
system('rm -rf .symlinks')
system('mkdir -p .symlinks/plugins')
plugin_pods = parse_KV_file('../.flutter-plugins')
plugin_pods.each do |name, path|
symlink = File.join('.symlinks', 'plugins', name)
File.symlink(path, symlink)
pod name, :path => File.join(symlink, 'ios')
end
end
# Prevent Cocoapods from embedding a second Flutter framework and causing an error with the new Xcode build system.
install! 'cocoapods', :disable_input_output_paths => true
post_install do |installer|
installer.pods_project.targets.each do |target|
target.build_configurations.each do |config|
config.build_settings['ENABLE_BITCODE'] = 'NO'
end
end
end
```
### Error
```
NoMethodError - undefined method `size' for nil:NilClass
/Library/Ruby/Gems/2.6.0/gems/ruby-macho-1.4.0/lib/macho/macho_file.rb:455:in `populate_mach_header'
/Library/Ruby/Gems/2.6.0/gems/ruby-macho-1.4.0/lib/macho/macho_file.rb:233:in `populate_fields'
/Library/Ruby/Gems/2.6.0/gems/ruby-macho-1.4.0/lib/macho/macho_file.rb:55:in `initialize_from_bin'
/Library/Ruby/Gems/2.6.0/gems/ruby-macho-1.4.0/lib/macho/macho_file.rb:33:in `new_from_bin'
/Library/Ruby/Gems/2.6.0/gems/ruby-macho-1.4.0/lib/macho/fat_file.rb:365:in `block in populate_machos'
/Library/Ruby/Gems/2.6.0/gems/ruby-macho-1.4.0/lib/macho/fat_file.rb:364:in `each'
/Library/Ruby/Gems/2.6.0/gems/ruby-macho-1.4.0/lib/macho/fat_file.rb:364:in `populate_machos'
/Library/Ruby/Gems/2.6.0/gems/ruby-macho-1.4.0/lib/macho/fat_file.rb:156:in `populate_fields'
/Library/Ruby/Gems/2.6.0/gems/ruby-macho-1.4.0/lib/macho/fat_file.rb:95:in `initialize'
/Library/Ruby/Gems/2.6.0/gems/ruby-macho-1.4.0/lib/macho.rb:31:in `new'
/Library/Ruby/Gems/2.6.0/gems/ruby-macho-1.4.0/lib/macho.rb:31:in `open'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/xcode/linkage_analyzer.rb:16:in `dynamic_binary?'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/sandbox/file_accessor.rb:171:in `block in vendored_dynamic_frameworks'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/sandbox/file_accessor.rb:170:in `select'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/sandbox/file_accessor.rb:170:in `vendored_dynamic_frameworks'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/sandbox/file_accessor.rb:179:in `vendored_static_frameworks'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/sandbox/file_accessor.rb:292:in `vendored_static_artifacts'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/installer/xcode/target_validator.rb:82:in `each'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/installer/xcode/target_validator.rb:82:in `flat_map'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/installer/xcode/target_validator.rb:82:in `block (2 levels) in verify_no_static_framework_transitive_dependencies'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/installer/xcode/target_validator.rb:74:in `each_key'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/installer/xcode/target_validator.rb:74:in `block in verify_no_static_framework_transitive_dependencies'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/installer/xcode/target_validator.rb:73:in `each'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/installer/xcode/target_validator.rb:73:in `verify_no_static_framework_transitive_dependencies'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/installer/xcode/target_validator.rb:38:in `validate!'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/installer.rb:590:in `validate_targets'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/installer.rb:158:in `install!'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/command/install.rb:52:in `run'
/Library/Ruby/Gems/2.6.0/gems/claide-1.0.3/lib/claide/command.rb:334:in `run'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/lib/cocoapods/command.rb:52:in `run'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.3/bin/pod:55:in `<top (required)>'
/usr/local/bin/pod:23:in `load'
/usr/local/bin/pod:23:in `<main>'
```
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[!] Oh no, an error occurred.
Search for existing GitHub issues similar to yours:
https://github.com/CocoaPods/CocoaPods/search?q=undefined+method+%60size%27+for+nil%3ANilClass&type=Issues
If none exists, create a ticket, with the template displayed above, on:
https://github.com/CocoaPods/CocoaPods/issues/new
Be sure to first read the contributing guide for details on how to properly submit a ticket:
https://github.com/CocoaPods/CocoaPods/blob/master/CONTRIBUTING.md
Don't forget to anonymize any private data!
Looking for related issues on cocoapods/cocoapods...
- NoMethodError - undefined method `size' for nil:NilClass
https://github.com/CocoaPods/CocoaPods/issues/8377 [closed] [14 comments]
a day ago
- NoMethodError - undefined method `each' for nil:NilClass
https://github.com/CocoaPods/CocoaPods/issues/9239 [closed] [5 comments]
a week ago
- NoMethodError - undefined method `size' for nil:NilClass
https://github.com/CocoaPods/CocoaPods/issues/9484 [closed] [9 comments]
14 Apr 2020
and 4 more at:
https://github.com/cocoapods/cocoapods/search?q=undefined%20method%20%60size%27%20for%20nil&type=Issues&utf8=✓
Error output from CocoaPods:
↳
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/universal-darwin19/rbconfig.rb:229: warning: Insecure world writable dir /Users/quentinguichot/Developer/flutter/bin in PATH, mode 040777
[!] Automatically assigning platform `iOS` with version `8.0` on target `Runner` because no platform was specified. Please specify a platform for this target in your Podfile. See `https://guides.cocoapods.org/syntax/podfile.html#platform`.
Finished with error: Error running pod install
答案 0 :(得分：0)
要解决此问题，请在终端中运行以下命令
for index, row in df2.iterrows():
cond = operator_dict[row["Operator"]](df1[row["Column"]],row["Value"])
print(pd.DataFrame(df1[row["Column"]][cond]))
答案 1 :(得分：0)
我发现的唯一解决方案是将Xcode降级到v11.4，某些软件包不兼容，并且在完成生产时遇到了问题