解决办法
http://stackoverflow.com/questions/33747828/a-build-only-device-cannot-be-used-to-run-this-target
i meet a problem that only "Generic iOS Device" can be choosed. and when i run ,it says "A build only device cannot be used to run this target.No supported iOS devices are available. Connect a device to run your application or choose a simulated device as the destination "
and my solution for the problem is selecting Build Settings ---> Deployment ----->IOS Deployment Target---->choose a lower version like 8.0,
and i found the simulator come out and can be chosen.
但是治标不治本，虽然能选择模拟器了，但问题还没解决
