在.pch文件中声明的内容，整个项目都可以用到， 创建.pch文件后需要配置一下
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#ifndef PrefixHeader_pch
#define PrefixHeader_pch
// Include any system framework and library headers here that should be included in all compilation units.
// You will also need to set the Prefix Header build setting of one or more of your targets to reference this file.
#import "UIView+Extension.h"
#import "NSArray+Log.h"
#import "NSDictionary+Log.h"
#import "UIBarButtonItem+BSExtention.h"
#import "BSConst.h"
#import "NSDate+BSExtension.h"
#ifdef DEBUG // 处于开发阶段
#define BSLog(...) NSLog(__VA_ARGS__)
#else // 处于发布阶段
#define BSLog(...)
#endif
// RGB颜色
#define BSColor(r, g, b) [UIColor colorWithRed:(r)/255.0 green:(g)/255.0 blue:(b)/255.0 alpha:1]
#define BSGlobalBg BSColor(223, 223, 223)
#define BSScreenW [UIScreen mainScreen].bounds.size.width
#define BSScreenH [UIScreen mainScreen].bounds.size.height
#define BSLogFunc BSLog(@"%s", __func__)
#endif /* PrefixHeader_pch */
