单例 实现 一个变量为 整个项目都可以用

单例究竟怎么传值？今天终于会了

.h

@interface MySharedClass : NSObject

@property (nonatomic, copy) NSString *sharedString;

+ (MySharedClass *)sharedInstance;

@end

.m

@implementation MySharedClass

+ (MySharedClass *)sharedInstance

{

static MySharedClass *sharedInstance = nil;

static dispatch_once_t onceToken;

dispatch_once(&onceToken, ^{

sharedInstance = [[MySharedClass alloc] init];

});

return sharedInstance;

}

@end

简单应用

[MySharedClass sharedInstance].sharedString