URLForResource returns nil

Question

I'm in the process of learning how to use xcode and how to write applications for the Mac.

So, I have a simple screensaver that loads an external file which works fine. I decided that it would be better to embed the html source in the application to reduce the external dependancies.

I dragged the HTML file to the resources folder, it's at the top level there's no sub folder or anything.

I made sure the Add to targets had my application in it, along with selecting 'create folder references' and 'copy files if needed'. I use the following to get the url to the file, but it returns nil

    NSURL *fileUrl = [[NSBundle mainBundle] URLForResource:@"embedded" withExtension:@"html"];


 System Preferences[10185]: fileUrl returned (null) 

I've read through all the other SO issues for the similar problems but none of the fixes seem to apply. I've gone through and checked them.

If I show the package contents of the final build the embedded.html is in there. Am I missing something really obvious?

edit to add

In build phases it's listed in Copy Bundle Resources

xcode version is 6.1.1

Answer 1

After some considerable digging and a smidgeon of luck I found that

    NSURL *fileUrl = [[NSBundle mainBundle] URLForResource:@"embedded" withExtension:@"html"];

is incorrect and I should be using

    NSURL *fileUrl = [[NSBundle bundleForClass:[self class]] URLForResource:@"embedded" withExtension:@"html"];

instead.

i.e. NSBundle bundleForClass:[self class] and not NSBundle mainBundle will give access to a screensaver bundle.

Might be obvious, but only if you know ;)

See Apple Developer NSBundle Class Reference