I found many ways on the Internet to no avail
Solution: 
1, Enter adb root in the cmd command window. (Invalid)
2, Restarting the phone is invalid (invalid)
3、Unplug and plug the phone again (I tried it, it didn't work) (invalid)
4, Restart appuim (invalid)
5, Restart uiautomatorviewer.bat (invalid)
6. Open the mobile phone developer permissions and restart the USB debugging button (ok)