为迅速

如果你在Xcode 12中使用CocoaPods，那么你可能会看到这个错误:

The iOS Simulator deployment target 'IPHONEOS_DEPLOYMENT_TARGET' is set to 8.0, but the range of supported deployment target versions is 9.0 to 14.

这是因为对iOS 8的支持已经放弃，但pod的最低部署目标是iOS 8。

在此问题解决之前，您可以将以下内容添加到Podfile中:

post_install do |installer|
  installer.pods_project.targets.each do |target|
    target.build_configurations.each do |config|
      config.build_settings.delete 'IPHONEOS_DEPLOYMENT_TARGET'
    end
  end
end

这将从项目中的所有pod中删除部署目标，并允许它们继承在Podfile顶部指定的项目/工作区部署目标。

对于React Native

删除。/project-root/ios/build文件夹，输入react-native run ios

为科尔多瓦

<preference name="deployment-target" value="8.0" />

我们可以将项目部署目标应用于所有pods目标。 通过在Podfile的末尾添加以下代码块来解决:

post_install do |installer|
  fix_deployment_target(installer)
end

def fix_deployment_target(installer)
  return if !installer
  project = installer.pods_project
  project_deployment_target = project.build_configurations.first.build_settings['IPHONEOS_DEPLOYMENT_TARGET']

  puts "Make sure all pods deployment target is #{project_deployment_target.green}"
  project.targets.each do |target|
    puts "  #{target.name}".blue
    target.build_configurations.each do |config|
      old_target = config.build_settings['IPHONEOS_DEPLOYMENT_TARGET']
      new_target = project_deployment_target
      next if old_target == new_target
      puts "    #{config.name}: #{old_target.yellow} -> #{new_target.green}"
      config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = new_target
    end
  end
end

结果记录:

迭代Tao-Nhan Nguyen的答案，计算每个pod的原始值集，只在它不大于8.0时调整它……在Podfile中添加以下内容:

post_install do |installer|
  installer.pods_project.targets.each do |target|
    target.build_configurations.each do |config|
      if Gem::Version.new('8.0') > Gem::Version.new(config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'])
        config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = '8.0'
      end
    end
  end
end

您所需要做的就是取消下面这一行的注释

# platform :ios, '8.0'

OR

# platform :ios, '9.0'

等等……

然后打开终端的iOS文件夹，传递这些命令:

% pod repo update
% pod install

对我有用:

rm ios/Podfile
flutter pub upgrade
flutter pub get
cd ios && pod update
flutter clean && flutter run
sudo arch -x86_64 gem install ffi
arch -x86_64 pod install 

我解决了这个问题，我把build system从New build system改为Legacy build system

在Xcode v10+中，选择文件>项目设置

在之前的Xcode中，选择File > Workspace Settings

将Build System从New Build System更改为Legacy Build System—>单击Done。