App TransportSecurity has blocked a cleartext HTTP (http://) resource load since it isinsecure. Temporary exceptions can be configured via your app's Info.plistfile.真机测试问题

“App Transport Security has blocked a cleartext HTTP (http://) resource load since it isinsecure. Temporary exceptions can be configured via your app's Info.plistfile.”
简而言之：ATS禁止了HTTP的明文传输，因为它不安全。可以修改Info.plist文件，让它临时允许明文传输。
解决办法：
在Info.plist文件中添加"App Transport SecuritySettings", Type为"Dictionary",再添加"Allow Arbitray Loads", Type 为"Boolean"，“Value”为“YES”即可。