嗨我有一个实现以前版本的iOS的单身如下:
.h文件
@interface CartSingleton : NSObject
{
}
+(CartSingleton *) getSingleton;
.m文件
@implementation CartSingleton
static CartSingleton *sharedSingleton = nil;
+(CartSingleton *) getSingleton
{
if (sharedSingleton !=nil)
{
NSLog(@"Cart has already been created.....");
return sharedSingleton;
}
@synchronized(self)
{
if (sharedSingleton == nil)
{
sharedSingleton = [[self alloc]init];
NSLog(@"Created a new Cart");
}
}
return sharedSingleton;
}
//==============================================================================
+(id)alloc
{
@synchronized([CartSingleton class])
{
NSLog(@"inside alloc");
NSAssert(sharedSingleton == nil, @"Attempted to allocate a second instance of a singleton.");
sharedSingleton = [super alloc];
return …