Macro definitions commonly used in IOS development

Sometimes, we need to make the code simple so that it's easy to read code. We can extract some unchanging stuff and change things as parameters. Defined as a macro, so it's much easier to write.

The following examples illustrate some common macro definitions and share them with you:

1. Determine if the device's operating system is IOS7

#define IOS7 ([[[  uidevice currentdevice].systemversion Doublevalue] >= 7.0])

2. Determine if the current device is IPhone5

#define KSCREENIPHONE5    ([[[UIScreen Mainscreen] bounds].size.height) >=568)

3. Get the height of the current screen

#define Kmainscreenheight ([UIScreen mainscreen].applicationframe.size.height)

4. Get the width of the current screen

#define Kmainscreenwidth  ([UIScreen mainscreen].applicationframe.size.width)

5. Get RGB color

#define Smscolor (R, G, b) [Uicolor colorwithred: (r)/255.0 Green: (g)/255.0 Blue: (b)/255.0 alpha:1.0]

6: Custom Log

#ifdef DEBUG

#define SMSLOG (...) NSLog (__va_args__)

#else

#define SMSLOG (...)

#endif

7. Single case

@interface # define SINGLETON_INTERFACE (ClassName) + (ClassName *) shared# #className;//@implementation # define Singleton_implementation (className) static className *_instance; + (ID) allocwithzone: (struct _nszone *) zone {     static dispatch_once_t Oncetoken;     Dispatch_once (&oncetoken, ^{         _instance = [Super Allocwithzone:zone];     });     return _instance; } + (ClassName *) shared# #className {     static dispatch_once_t Oncetoken;     Dispatch_once (&oncetoken, ^{         _instance = [[Self alloc] init];     });     return _instance; }