ionic3 - Apple Mach -O Linker (Id) Error?

Question

This is the all error showing:

Apple Mach -O Linker (Id) Error? 
"Linker command failed with exit code 1 (use -v to see invocation). 

After I install OneSignal plugin in my ionic3 project, haven't setup all , When I tried to run my project in my device, this error coming out.

And when I open .xcworkspace file, two project showing to me. First one is my real project, last one is after I install OneSignal plugin and install sudo gem install cocoapods, pod repo update then showing

Just now I tried run ionic cordova run ios --device that can run in my device, but when I use xcode and hit play button which cannot run in my device and showing the error that my question title

Answer 1

1.Please install the pod file and always open with .xcworkspace.

2.Check if any files is deleted from the path (shown in red in workspace), please remove all red files.

3.Check whether files is set for the same target(if not please set all the files for the required targets).

4.Check the settings to add files.

Hope above points resolve your problem.

Answer 2

Finally I found the way to solve this error!

Because I install pod for push notification fucntion, so try to use the .xcworkspace file to run the project after pod install instead of .xcodeproj file.

But I still don't know why .xcworkspace will showing this error when I install pod, if you know comment here please, thanks a lot!