`react-native run-ios`返回错误：找不到iPhone X模拟器

每当我跑步时react-native run-ios，我都会

Could not find iPhone X simulator

Error: Could not find iPhone X simulator
    at resolve (calendarPractice/node_modules/react-native/local-cli/runIOS/runIOS.js:149:13)
    at new Promise (<anonymous>)
    at runOnSimulator (calendarPractice/node_modules/react-native/local-cli/runIOS/runIOS.js:134:10)
    at Object.runIOS [as func] (calendarPractice/node_modules/react-native/local-cli/runIOS/runIOS.js:106:12)
    at Promise.resolve.then (calendarPractice/node_modules/react-native/local-cli/cliEntry.js:117:22)

但是，当我在Xcode上运行时，它工作正常

{
  "devicetypes" : [
    {
      "name" : "iPhone 4s",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone 4s.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-4s"
    },
    {
      "name" : "iPhone 5",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone 5.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-5"
    },
    {
      "name" : "iPhone 5s",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone 5s.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-5s"
    },
    {
      "name" : "iPhone 6",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone 6.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-6"
    },
    {
      "name" : "iPhone 6 Plus",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone 6 Plus.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-6-Plus"
    },
    {
      "name" : "iPhone 6s",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone 6s.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-6s"
    },
    {
      "name" : "iPhone 6s Plus",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone 6s Plus.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-6s-Plus"
    },
    {
      "name" : "iPhone 7",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone 7.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-7"
    },
    {
      "name" : "iPhone 7 Plus",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone 7 Plus.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-7-Plus"
    },
    {
      "name" : "iPhone 8",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone 8.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-8"
    },
    {
      "name" : "iPhone 8 Plus",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone 8 Plus.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-8-Plus"
    },
    {
      "name" : "iPhone SE",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone SE.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-SE"
    },
    {
      "name" : "iPhone X",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone X.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-X"
    },
    {
      "name" : "iPhone Xs",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone Xs.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-XS"
    },
    {
      "name" : "iPhone Xs Max",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone Xs Max.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-XS-Max"
    },
    {
      "name" : "iPhone Xʀ",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPhone Xʀ.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPhone-XR"
    },
    {
      "name" : "iPad 2",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPad 2.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPad-2"
    },
    {
      "name" : "iPad Retina",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPad Retina.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPad-Retina"
    },
    {
      "name" : "iPad Air",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPad Air.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPad-Air"
    },
    {
      "name" : "iPad Air 2",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPad Air 2.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPad-Air-2"
    },
    {
      "name" : "iPad (5th generation)",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPad (5th generation).simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPad--5th-generation-"
    },
    {
      "name" : "iPad Pro (9.7-inch)",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPad Pro (9.7-inch).simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPad-Pro--9-7-inch-"
    },
    {
      "name" : "iPad Pro (12.9-inch)",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPad Pro (12.9-inch).simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPad-Pro"
    },
    {
      "name" : "iPad Pro (12.9-inch) (2nd generation)",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPad Pro (12.9-inch) (2nd generation).simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPad-Pro--12-9-inch---2nd-generation-"
    },
    {
      "name" : "iPad Pro (10.5-inch)",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPad Pro (10.5-inch).simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPad-Pro--10-5-inch-"
    },
    {
      "name" : "iPad (6th generation)",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPad (6th generation).simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPad--6th-generation-"
    },
    {
      "name" : "iPad Pro (11-inch)",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPad Pro (11-inch).simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPad-Pro--11-inch-"
    },
    {
      "name" : "iPad Pro (12.9-inch) (3rd generation)",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/iPad Pro (12.9-inch) (3rd generation).simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.iPad-Pro--12-9-inch---3rd-generation-"
    },
    {
      "name" : "Apple TV",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/AppleTVOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/Apple TV.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.Apple-TV-1080p"
    },
    {
      "name" : "Apple TV 4K",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/AppleTVOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/Apple TV 4K.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.Apple-TV-4K-4K"
    },
    {
      "name" : "Apple TV 4K (at 1080p)",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/AppleTVOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/Apple TV 4K (at 1080p).simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.Apple-TV-4K-1080p"
    },
    {
      "name" : "Apple Watch - 38mm",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/WatchOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/Apple Watch - 38mm.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.Apple-Watch-38mm"
    },
    {
      "name" : "Apple Watch - 42mm",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/WatchOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/Apple Watch - 42mm.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.Apple-Watch-42mm"
    },
    {
      "name" : "Apple Watch Series 2 - 38mm",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/WatchOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/Apple Watch Series 2 - 38mm.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.Apple-Watch-Series-2-38mm"
    },
    {
      "name" : "Apple Watch Series 2 - 42mm",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/WatchOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/Apple Watch Series 2 - 42mm.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.Apple-Watch-Series-2-42mm"
    },
    {
      "name" : "Apple Watch Series 3 - 38mm",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/WatchOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/Apple Watch Series 3 - 38mm.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.Apple-Watch-Series-3-38mm"
    },
    {
      "name" : "Apple Watch Series 3 - 42mm",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/WatchOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/Apple Watch Series 3 - 42mm.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.Apple-Watch-Series-3-42mm"
    },
    {
      "name" : "Apple Watch Series 4 - 40mm",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/WatchOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/Apple Watch Series 4 - 40mm.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.Apple-Watch-Series-4-40mm"
    },
    {
      "name" : "Apple Watch Series 4 - 44mm",
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/WatchOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/DeviceTypes\/Apple Watch Series 4 - 44mm.simdevicetype",
      "identifier" : "com.apple.CoreSimulator.SimDeviceType.Apple-Watch-Series-4-44mm"
    }
  ],
  "runtimes" : [
    {
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/iPhoneOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/Runtimes\/iOS.simruntime",
      "availabilityError" : "",
      "buildversion" : "16B91",
      "availability" : "(available)",
      "isAvailable" : true,
      "identifier" : "com.apple.CoreSimulator.SimRuntime.iOS-12-1",
      "version" : "12.1",
      "name" : "iOS 12.1"
    },
    {
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/AppleTVOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/Runtimes\/tvOS.simruntime",
      "availabilityError" : "",
      "buildversion" : "16J602",
      "availability" : "(available)",
      "isAvailable" : true,
      "identifier" : "com.apple.CoreSimulator.SimRuntime.tvOS-12-1",
      "version" : "12.1",
      "name" : "tvOS 12.1"
    },
    {
      "bundlePath" : "\/Applications\/Xcode.app\/Contents\/Developer\/Platforms\/WatchOS.platform\/Developer\/Library\/CoreSimulator\/Profiles\/Runtimes\/watchOS.simruntime",
      "availabilityError" : "",
      "buildversion" : "16R591",
      "availability" : "(available)",
      "isAvailable" : true,
      "identifier" : "com.apple.CoreSimulator.SimRuntime.watchOS-5-1",
      "version" : "5.1",
      "name" : "watchOS 5.1"
    }
  ],
  "devices" : {
    "com.apple.CoreSimulator.SimRuntime.watchOS-5-1" : [
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "Apple Watch Series 2 - 38mm",
        "udid" : "01AFDEF7-63B6-465C-A02A-44EE4A07EABA",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "Apple Watch Series 2 - 42mm",
        "udid" : "BE62C985-DEE2-46EC-8962-A582D537EEE0",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "Apple Watch Series 3 - 38mm",
        "udid" : "078BF157-30FA-41D1-94FA-6B1686E03085",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "Apple Watch Series 3 - 42mm",
        "udid" : "E4CE652E-0185-4C59-B965-BED5FCEE7C76",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "Apple Watch Series 4 - 40mm",
        "udid" : "6621323A-A9DE-4BCB-AC97-54C8C33B0158",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "Apple Watch Series 4 - 44mm",
        "udid" : "D89037A3-66A0-43C1-90BA-E7C76CA0D724",
        "availabilityError" : ""
      }
    ],
    "com.apple.CoreSimulator.SimRuntime.tvOS-12-1" : [
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "Apple TV",
        "udid" : "AFAA21B8-BD4A-45EA-B0FF-E9915FE9B926",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "Apple TV 4K",
        "udid" : "EBB88F2E-CFFE-4981-A736-7A7C0B85643D",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "Apple TV 4K (at 1080p)",
        "udid" : "F0B73E8A-986E-447E-B37A-2F46096DEFF6",
        "availabilityError" : ""
      }
    ],
    "com.apple.CoreSimulator.SimRuntime.iOS-12-1" : [
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone 5s",
        "udid" : "F870B7FA-6DDA-4336-89AD-68A402844188",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone 5s",
        "udid" : "6627ADE5-F8C1-4AE5-BD6F-3AEDDC0B7B63",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone 6",
        "udid" : "05574997-ACAD-40CA-A3D7-5624D53F00FA",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone 6 Plus",
        "udid" : "93237078-CA6D-4F97-93F9-779809700018",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone 6s",
        "udid" : "9B50FE18-4F49-4EA4-80F0-DF498A667D33",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone 6s Plus",
        "udid" : "D4640B6D-97DC-4CA1-BE63-C5403159A3D4",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone 7",
        "udid" : "6E9EEC00-3291-42B4-B04A-BA3487F9CD5F",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone 7 Plus",
        "udid" : "6DA1C3CF-1D1F-4DEF-9B74-2C40D5FB5881",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone 8",
        "udid" : "E19386B9-469A-450B-9CD2-B4FE8687DCF9",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone 8 Plus",
        "udid" : "6D36DF76-8ED9-41A2-9E1A-0BA48B92C26E",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone SE",
        "udid" : "EE4818DF-F817-4441-8A1C-BE1B99303E10",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone X",
        "udid" : "85B78A8F-C32B-4493-BDD1-65ECA3F77C86",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone X",
        "udid" : "CA12C337-4F66-4C6C-ACE5-7F7EACCBC39A",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone XS",
        "udid" : "8BBCE315-2F4C-4132-8E53-28AF52401C8E",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone XS Max",
        "udid" : "4E77C62F-AB1F-4EDE-839B-53F70CAFC79E",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPhone XR",
        "udid" : "28D12ABE-3355-4862-960A-0FE5FFE41C7B",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPad Air",
        "udid" : "94485C88-BCEB-456A-95DC-5F8C3DA8D181",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPad Air 2",
        "udid" : "CF2C787D-A378-4AB9-B334-F7B24E94AF4D",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPad (5th generation)",
        "udid" : "DFE602A5-EC68-4585-8AB0-C045A9843D29",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPad Pro (9.7-inch)",
        "udid" : "5A3F3EAC-F788-49F1-A753-5D34A9990F0B",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPad Pro (12.9-inch)",
        "udid" : "EF6EBE34-0A85-4FF0-8A45-7BA418A0CC0C",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPad Pro (12.9-inch) (2nd generation)",
        "udid" : "FBA940F8-FD85-4D5E-A570-EB4F3A56E1F9",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPad Pro (10.5-inch)",
        "udid" : "8AE4AAED-ECE0-4984-9679-8D3022064692",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPad (6th generation)",
        "udid" : "1121363D-EF49-4AC0-9E46-5C30318A24A2",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPad Pro (11-inch)",
        "udid" : "038FECC0-8711-46E3-B601-8F88F2F4AD7D",
        "availabilityError" : ""
      },
      {
        "availability" : "(available)",
        "state" : "Shutdown",
        "isAvailable" : true,
        "name" : "iPad Pro (12.9-inch) (3rd generation)",
        "udid" : "12DC911F-2F45-4767-BC1A-6F1D0C8D9F3D",
        "availabilityError" : ""
      }
    ]
  },
  "pairs" : {
    "C9B69F4A-6A9D-44F3-A6BC-56BFA2F8B83F" : {
      "watch" : {
        "name" : "Apple Watch Series 4 - 44mm",
        "udid" : "D89037A3-66A0-43C1-90BA-E7C76CA0D724",
        "state" : "Shutdown"
      },
      "phone" : {
        "name" : "iPhone XS Max",
        "udid" : "4E77C62F-AB1F-4EDE-839B-53F70CAFC79E",
        "state" : "Shutdown"
      },
      "state" : "(active, disconnected)"
    },
    "5327B65F-29E7-42D0-9861-FF31428F3218" : {
      "watch" : {
        "name" : "Apple Watch Series 4 - 40mm",
        "udid" : "6621323A-A9DE-4BCB-AC97-54C8C33B0158",
        "state" : "Shutdown"
      },
      "phone" : {
        "name" : "iPhone XS",
        "udid" : "8BBCE315-2F4C-4132-8E53-28AF52401C8E",
        "state" : "Shutdown"
      },
      "state" : "(active, disconnected)"
    }
  }

编辑：我复制了输出JSON的“设备”部分并将其嵌入到我自己的设备中 /node_modules/react-native/local-cli/runIOS/runIOS.js

function runOnSimulator(xcodeProject, args, scheme) {
return new Promise(resolve => {
    try {
        var simulators = {devices section of your json}; //Here
    } catch (e) {
        console.log("e", e);
        throw new Error('Could not parse the simulator list output');
    }

    const selectedSimulator = findMatchingSimulator(simulators, args.simulator);
    console.log("selected", selectedSimulator);
    if (!selectedSimulator) {
        throw new Error(`Could not find ${args.simulator} simulator`);
    }
    ...

最后，它给出了与您相同的错误。因此，我发现设备的解析版本有所不同。在您的设备中，版本为；

"com.apple.CoreSimulator.SimRuntime.tvOS-12-1" //for tvOS
"com.apple.CoreSimulator.SimRuntime.iOS-12-1" // for iOS

但在本机检查中，此版本值类似于this（/node_modules/react-native/local-cli/runIOS/findMatchingSimulator.js）;

// Making sure the version of the simulator is an iOS or tvOS (Removes Apple Watch, etc)
if (!version.startsWith('iOS') && !version.startsWith('tvOS')) {
    continue;
}

所以反应本机无法识别。
如果我们以此来更改此代码；

// Making sure the version of the simulator is an iOS or tvOS (Removes Apple Watch, etc)
if (!version.startsWith('com.apple.CoreSimulator.SimRuntime.iOS') && !version.startsWith('com.apple.CoreSimulator.SimRuntime.tvOS')) {
    continue;
}

问题解决了。我在计算机上检查了您的JSON数据后，它是否有效。

要解决此错误，只需使用npm重新安装项目和节点模块

npm install

然后，它将显示警告列表，并使用以下命令修复它们：

npm audit fix

这应该可以解决所有问题，并允许您运行iOS模拟器 react-native run-ios

问题

如果您使用最新的Xcode（11）进行尝试，则没有iPhone X！

单独运行模拟器，在顶部菜单中，在“硬件，设备，iOS 13.0”下查看。您将看到：

• iPhone 8
• iPhone 8 Plus
• iPhone XS
• iPhone XS最大
• iPhone XR
• ...和一些iPad

执行时run-ios，react-native旨在匹配请求的设备。

内部硬编码默认值为iPhoneX。

尝试与请求的设备匹配的函数在：

/node_modules/@react-native-community/cli-platform-ios/build/commands/runIOS/findMatchingSimulator.js

设计此功能是为了使您可以为其提供设备和可选的版本号。

如果找不到给定的设备和版本，则默认情况下它将使用列表中的第一个设备返回匹配项。

但是...实际上，第一个设备是手表，并且所有手表都不匹配，因此此函数将返回null。

解决方案1-使用现有的Xcode设备

如上所述，首先自己运行模拟器，并记下所需的iPhone或iPad。

然后将此名称作为可选参数传递给run-ios命令行命令，如下所示：

react-native run-ios --simulator="iPhone 8"

解决方案2-添加新的Xcode iOS设备

根据Xcode 11发行说明：

“默认情况下，Xcode不再创建每个可用的iOS模拟器设备。而是创建了一组最常用的设备。要创建其他设备（或一个设备的多个实例），请打开“设备”窗口，选择模拟器，点击+按钮，输入名称，然后选择相关的设备类型和操作系统版本。在终端中，执行xcrun simctl create命令，例如xcrun simctl create“ My iPhone 7”“ iPhone 7” iOS13.0。（49428617）“

在Xcode中，您需要添加一个名为“ iPhone X”的新设备。

我也在这里回答：React Native Issue＃2328

临时修复：

步骤1：打开文件/node_modules/react-native/local-cli/runIOS/findMatchingSimulator.js

步骤2：从此更改一行代码：

if (!version.startsWith('iOS') && !version.startsWith('tvOS')) {
  continue;
}

对此：

if (!version.startsWith('com.apple.CoreSimulator.SimRuntime.iOS') && !version.startsWith('com.apple.CoreSimulator.SimRuntime.tvOS')) {
  continue;
}

步骤3：执行react-native run-ios（您可能需要运行两次，并且如果它是从先前的不成功构建中运行的，请不要忘记杀死Metro Bundler [正在后台运行的控制台！）

问题是，在更新Xcode之后-模拟器名称空间已添加到设备的版本列表中。React Native构建并不期望这些名称空间-因此构建中断。

更新到Xcode 11之后，xcrun返回true或false，而不是像以前那样是YES或NO。

转到/node_modules/react-native/local-cli/runIOS/findMatchingSimulator.js和

找

if (
   simulator.availability !== '(available)' &&
   simulator.isAvailable !== 'YES'
 ) {
  continue;
}

并将其更改为

if (
   simulator.availability !== '(available)' &&
   simulator.isAvailable !== true
 ) {
  continue;
}

您的计算机上没有iPhone X模拟器，很可能是因为您更新了Xcode。您可以简单地传递可用模拟器的名称，如下所示：

react-native run-ios --simulator="iPhone 11"

要检查可用的模拟器，可以打开Xcode并检查设备列表，如下所示：

打开文件/node_modules/react-native/local-cli/runIOS/findMatchingSimulator.js

！version.startsWith（'iOS'）->！version。包括（“ iOS”）

将Xcode更新到版本11后，我遇到了相同的问题。

一种解决方案是将iPhone X模拟器添加到您的列表中。

• 选择模拟器->硬件->管理设备（您将看到一个弹出窗口）

• 选择“模拟器”->（左下角）+（“过滤器”旁边的加号图标），然后添加一个新的模拟器，

• 模拟器名称：iPhone X设备类型：选择iPhoneX。

对我有用

我也没有在Xcode上安装iPhone X作为模拟器。我要做的就是在Xcode中将iPhone X添加为新的模拟器，一切都很好。

在Xcode中：转到Windowthen Devices and Simulators。单击模拟器选项卡。点击+左下角按钮，然后添加iPhoneX。

我希望此修复程序对您和对我一样容易。

在我的情况下，我运行脚本：sed -i'''s / startsWith / includes / g'node_modules / react-native / local-cli / runIOS / findMatchingSimulator.js，它起作用了。也适合无法更新本机的人

对于Xcode 11.2和iOS 13.2，以下是我在模拟器中运行该应用程序所做的更改

在 findMatchingSimulator.js

第43行：

if (!version.startsWith('iOS') && !version.startsWith('tvOS')) {

至

if (!version.includes('iOS') && !version.includes('tvOS')) {

线

52行

if (
    simulator.availability !== '(available)' &&
    simulator.isAvailable !== 'YES'
  ) {
    continue;
  }

至

if (
    simulator.isAvailable != true
  ) {
    continue;
  }

聚苯乙烯

React项目广告的第一天已经降价了！（没有）

我的问题是未安装iPhone X模拟器

您可以检查安装了哪些模拟器

xcrun simctl list devices | grep iPhone | grep -v unavailable | cut -d'(' -f1

然后跑

react-native run-ios --simulator="iPhone Xs"

如果找不到，请在替换runSimulator.js中的以下代码后，模拟器仍然存在。

runSimulator.js的路径-> /node_modules/react-native/local-cli/runIOS/findMatchingSimulator.js

if (!version.startsWith('iOS') && !version.startsWith('tvOS')) { continue; }

与这个

if ( !version.startsWith('com.apple.CoreSimulator.SimRuntime.iOS') && !version.startsWith('com.apple.CoreSimulator.SimRuntime.tvOS') ) { continue; }

替换后在以下几行中添加注释

if ( simulator.availability !== '(available)' && simulator.isAvailable !== 'YES' ) { continue; }

它将毫无问题地启动iPhone模拟器。

和第二种方法更新到XCode 11之后

Xcode 11 xcrun返回true或false，而不是像以前一样为isAvailable属性返回YES或NO 。您可以使用以下命令检查

xcrun simctl list devices --json 

上面的命令将打印所有可用的设备，如下所示

"com.apple.CoreSimulator.SimRuntime.iOS-12-2" : [
  {
    "state" : "Booted",
    "isAvailable" : true,
    "name" : "iPhone X",
    "udid" : "E53748D1-628B-4A99-A419-4D7AE7CE4745"
  }
]

在以下代码中将YES替换为 true

if ( simulator.availability !== '(available)' && simulator.isAvailable !== 'YES' ) { continue; }

像这样

if ( simulator.availability !== '(available)' && simulator.isAvailable !== true ) { continue; }

容易修复...

Xcode->首选项->组件安装iOS 12.2汇总器

更改 /node_modules/@react-native-community/cli-platform-ios/build/commands/runIOS/index.js

文件

options: [{
    name: '--simulator [string]',
    description: 'Explicitly set simulator to use. Optionally include iOS version between' + 'parenthesis at the end to match an exact version: "iPhone 6 (10.0)"',
    default: 'iPhone X'
  }

至

options: [{
    name: '--simulator [string]',
    description: 'Explicitly set simulator to use. Optionally include iOS version between' + 'parenthesis at the end to match an exact version: "iPhone 6 (10.0)"',
    default: 'iPhone 8'
  }

当我将Xcode 10升级到Xcode 11时遇到了相同的错误，但是指定模拟器版本对我来说是一个快速修复。

首先列出所有可用的ios模拟器

  xcrun simctl list devices | grep iPhone | grep -v unavailable | cut -d'(' -f1

结果

然后选择一个运行本机，例如

 react-native run-ios --simulator='iPhone 11 Pro Max'

使用react-native-cli 2.0.1，您可能只想重命名模拟器。默认情况下，Xcode将以格式命名某些设备<DeviceName> (<DeviceSize>)。但是，此版本的CLI会将括号中的内容解释为iOS版本。

尝试运行名为的模拟器时iPad Pro (10.5-inch)，只需将模拟器重命名为，即可使其运行iPad Pro [10.5-inch]。

您可以通过使用Simulator应用程序的Hardware-> Device-> Manage Devices...菜单重命名模拟器 ，然后右键单击其中一个模拟器（在Xcode 10.2.1中）

更新Xcode时遇到了问题。所有模拟器均不可用/未安装。我将再次安装它们。

就我而言，我已经尝试了其他解决方案，但没有任何效果。

然后我尝试将react-native从升级0.59.5到，0.59.10然后解决了

我试图从提升本土做出反应之后遇到这个问题0.59.8来0.59.9。

事实证明（基于以上答案），我们需要更新@react-native-community/cli模块：

1. 从锁文件中将其删除（yarn.lock或package-lock.json）
2. 运行yarn或npm install重新安装。

参考：https : //github.com/react-native-community/rn-diff-purge/issues/21#issuecomment-507645945

对我来说，我必须通过运行将React Native更新到0.60 npx react-native-git-upgrade。

每次更新Xcode时，我都会遇到相同的问题。
我运行以下命令：

sudo killall -9 com.apple.CoreSimulator.CoreSimulatorService

然后我又跑react-native run-ios了。

只需重新启动计算机，然后再次运行命令。