UIColorでRGBをHex(16進数)で指定出来てアルファもキメちゃうマクロ ref: http://qiita.com/unamu/items/61ec0a99419d5afafdb9

file0.txt

//RGB color macro
#define UIColorFromRGB(rgbValue) [UIColor \
colorWithRed:((float)((rgbValue & 0xFF0000) >> 16))/255.0 \
green:((float)((rgbValue & 0xFF00) >> 8))/255.0 \
blue:((float)(rgbValue & 0xFF))/255.0 alpha:1.0]

//RGB color macro with alpha
#define UIColorFromRGBWithAlpha(rgbValue,a) [UIColor \
colorWithRed:((float)((rgbValue & 0xFF0000) >> 16))/255.0 \
green:((float)((rgbValue & 0xFF00) >> 8))/255.0 \
blue:((float)(rgbValue & 0xFF))/255.0 alpha:a]

file1.txt

self.view.backgroundColor = UIColorFromRGB(0xCECECE);
self.view.backgroundColor = UIColorFromRGBWithAlpha(0xCECECE, 0.8);