project always running with old code

I was trying to try out and create a .app file for my application and so I followed a tutorial. 开发者_C百科After doing this and running the app again on the simulator it always runs with the old code that I have. Why is this? I tried reverting everything back again, but it just won't.

I tried printing something when the app loads, but the app that runs didn't print anything UPDATE:

I found a fix which is to revert back my bundle identifier to the old one. Why does this work? What if I want to create a binary again to be distributed in the app store, what should I do from this point?

You probably have two apps with the same bundle identifier on the simulator, and Xcode starts the wrong one.

Try to delete everything from the simulator.
Open the iOS Simulator menu in the main menu and select Reset Content and Settings...

I've had the same problem before and for some reason it just didn't update all the files in the bundle that it deployed to the device/simulator. Just delete the app from the device/simulator and redeploy. When it happened to me it didn't create a second app it just didn't completely update the bundle.