Macros for generating UIColor instances only once, increasing application performance.

AGEColor

//
// AGEColor.h
//
// Copyright (c) 2013 Alexander Edge (http://www.alexedge.co.uk)
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

#define AGEColorDefine(COLOR_NAME)    \
+ (UIColor *)COLOR_NAME;

#define AGEColorImplement(COLOR_NAME,COLOR)    \
+ (UIColor *)COLOR_NAME{    \
static UIColor* COLOR_NAME##_color;    \
static dispatch_once_t COLOR_NAME##_onceToken;   \
dispatch_once(&COLOR_NAME##_onceToken, ^{    \
COLOR_NAME##_color = COLOR;  \
}); \
return COLOR_NAME##_color;  \
}