OC单例快速实现
首先新建一个头文件,定义如下宏:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
|
// .h文件的实现 #define SingletonH(methodName) + (instancetype)shared##methodName; // .m文件的实现 #if __has_feature(objc_arc) // 是ARC #define SingletonM(methodName) \ static id _instace = nil ; \ + ( id )allocWithZone:( struct _NSZone *)zone \ { \ if (_instace == nil ) { \ static dispatch_once_t onceToken; \ dispatch_once(&onceToken, ^{ \ _instace = [ super allocWithZone:zone]; \ }); \ } \ return _instace; \ } \ \ - ( id )init \ { \ static dispatch_once_t onceToken; \ dispatch_once(&onceToken, ^{ \ _instace = [ super init]; \ }); \ return _instace; \ } \ \ + (instancetype)shared##methodName \ { \ return [[ self alloc] init]; \ } \ + ( id )copyWithZone:( struct _NSZone *)zone \ { \ return _instace; \ } \ \ + ( id )mutableCopyWithZone:( struct _NSZone *)zone \ { \ return _instace; \ } #else // 不是ARC #define SingletonM(methodName) \ static id _instace = nil ; \ + ( id )allocWithZone:( struct _NSZone *)zone \ { \ if (_instace == nil ) { \ static dispatch_once_t onceToken; \ dispatch_once(&onceToken, ^{ \ _instace = [ super allocWithZone:zone]; \ }); \ } \ return _instace; \ } \ \ - ( id )init \ { \ static dispatch_once_t onceToken; \ dispatch_once(&onceToken, ^{ \ _instace = [ super init]; \ }); \ return _instace; \ } \ \ + (instancetype)shared##methodName \ { \ return [[ self alloc] init]; \ } \ \ - (oneway void )release \ { \ \ } \ \ - ( id )retain \ { \ return self ; \ } \ \ - ( NSUInteger )retainCount \ { \ return 1; \ } \ + ( id )copyWithZone:( struct _NSZone *)zone \ { \ return _instace; \ } \ \ + ( id )mutableCopyWithZone:( struct _NSZone *)zone \ { \ return _instace; \ } #endif |
然后在你定义单例类的
.h 文件 写 SingletonH(MyMethodName)
.m 文件写 SingletonM(MyMethodName)
搞定!