单例的的销毁与重建
static MusesEditLog *instance = nil;
static dispatch_once_t onceToken;
+ (instancetype)shared {
dispatch_once(&onceToken, ^{
instance = [[[self class] alloc] init];
});
return instance;
}
+ (void)dispose {
instance = nil;
onceToken = 0l;
}
（Weak Singleton）弱单例优化
在 OC 中
+ (instancetype)shared
{
static __weak ACGUtility *instance;
ACGUtility *strongInstance = instance;
@synchronized(self) {
if (strongInstance == nil) {
strongInstance = [[[self class] alloc] init];
instance = strongInstance;
}
}
return strongInstance;
}
在 swift 中
static weak var weakInstance: ACGUtility?
static var sharedInstance: ACGUtility {
get {
if let instance = weakInstance {
return instance
} else {
let newInstance = ACGUtility()
weakInstance = newInstance
return newInstance
}
}
}
优化前：
image.png
优化后：
image.png
