我使用ionic建立了一个项目，但出现此错误
.2019-06-26 15:41:20.703 MyApp[457:65172] DiskCookieStorage changing policy from 2 to 0, cookie file: file:///private/var/mobile/Containers/Data/Application/0FC3284F-9D2D-4DBF-81AF-6802E4FDA2F1/Library/Cookies/Cookies.binarycookies
2019-06-26 15:41:20.827 MyApp[457:65172] Apache Cordova native platform version 5.0.1 is starting.
2019-06-26 15:41:20.829 MyApp[457:65172] Multi-tasking -> Device: YES, App: YES
2019-06-26 15:41:20.878 MyApp[457:65172] CDVWKWebViewEngine: trying to inject XHR polyfill
2019-06-26 15:41:20.892 MyApp[457:65172] -[WKWebViewConfiguration setMediaTypesRequiringUserActionForPlayback:]: unrecognized selector sent to instance 0x17e806a0
2019-06-26 15:41:20.894 MyApp[457:65172] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[WKWebViewConfiguration setMediaTypesRequiringUserActionForPlayback:]: unrecognized selector sent to instance 0x17e806a0'
*** First throw call stack:
(0x24bff91b 0x2439ae17 0x24c052b5 0x24c02ee1 0x24b2e238 0xaf009 0xafb23 0xcb13f 0xca8df 0xcad7d 0xc83f1 0x5e6fb 0x2917ad8b 0x2917a971 0x29181639 0x2917eb3d 0x291f3a5d 0xbe1c7 0x5e4d1 0x291ef785 0x294172d1 0x2941b285 0x2942f83d 0x294187b3 0x262a2c07 0x262a2ab9 0x262a2db9 0x24bc1dff 0x24bc19ed 0x24bbfd5b 0x24b0f229 0x24b0f015 0x291e8c3d 0x291e3189 0x5e3cb 0x247b7873)
libc++abi.dylib: terminating with uncaught exception of type NSExcepti
上
我的离子信息是 离子性：
ionic（Ionic CLI）：4.12.0（/ Users / sysadmin / node_modules / ionic） 离子框架：@ ionic / angular 4.5.0 @ angular-devkit / build-angular：0.13.9 @ angular-devkit / schematics：7.3.9 @ angular / cli：7.3.9 @ ionic / angular-toolkit：1.5.1
科尔多瓦：
cordova（Cordova CLI）：9.0.0（cordova-lib@9.0.1） Cordova平台：iOS 5.0.1 Cordova插件：cordova-plugin-ionic-keyboard 2.1.3，cordova-plugin-ionic-webview 4.1.0（和其他7个插件）
系统：
ios部署：1.9.4 ios-sim：8.0.1 NodeJS：v11.9.0（/Users/sysadmin/.nvm/versions/node/v11.9.0/bin/node） npm：6.9.0 操作系统：macOS High Sierra Xcode：Xcode 9.2 Build 9C40b