mac issue

I have a UIView and I'm trying to set its layer properties.

self.colorSwatch = [[UIView alloc] initWithFrame:CGRectMake(400, 150, 100, 100)];
self.colorSwatch.layer.cornerRadius = 8; 

However, when I try to access the .layer.cornerRadius property, I get a warning that says "Property 'cornerRadius' cannot be found in forward class object 'CALayer *'.

What does this mean? Thanks

http://stackoverflow.com/questions/9829371/property-cannot-be-found-on-forward-class-object

(null): "_OBJC_CLASS_$_Demo1ViewController", referenced from:

http://stackoverflow.com/questions/4965555/objective-c-class-reference-symbols-not-found-error

Most likely these three classes are missing from your project file. Check the Classes group in your XCode project to see if these three files are present. If not, then right-click the Classes group, and click Add > Existing Files to add them.

If the files are added to the project, then make sure that the implementation (.m) files for these missing classes are added to compiled sources. To check that, expand the group Targets > Build Phases > Compile Sources, and see if the files are present. If not, right click on "Compile Sources", and goto Add > Existing Files to add them. An alternative and maybe quicker way to do the same is by selecting the .m files for each of the missing classes, and see if the bulls eye checkbox on the far right is checked. If not, then check it and it will automatically get added to Compiled Sources.

iPhone如何打包成一个通用的静态库文件(模拟器和真机都可以用)？

http://xbiii3s.iteye.com/blog/1462627