Xcode run device changed from Iphone/ipad to my Mac solution

First of all, how to resolve the device column display "My mac" problem: Children's shoes are known that Xcode will display the appropriate simulator for developers to choose based on the current SDK in the options bar next to the Run button, but sometimes the error "My Mac" is obviously not what we want. The main reason for this is that when you open another Mac computer copy of the project or other causes appear, then the solution is given here:

Resolution Step: First close your Xcode, find the project directory where you have resolved this issue, and then this item * * *. xcodeproj file, then right-select "Show Package Contents", in general, there are the following 3 files in the package: 1.project.pbxproj 2.project.xcworkspace 3.xcuserdata. Find the culprit of "xcuserdata" and move it all the way to the trash, OK, reopen your project, and the available simulator will be displayed normally.

Xcode run device changed from Iphone/ipad to my Mac solution