Cannot replace an image by replacing the image files in Finder

I would like to update some images (gif) in my application. After replacing the gif files in the folder, I build the application and run it; the images shown in simulator are not updated. I tried to "Clear all target" and then re-built开发者_如何学Go the application; the new images can be shown in the simulator.

Does it mean the images will be successfully updated in the devices which have installed the older version of the application? Should I modify the code?

You would need to "Replace" those image by the same names as in the earlier build.In this way even if your app is in the App Store, after submitting your update with the new images having the same names can be updated easily.

No need to modify your code.