详解IOS 单例的两种方式

第详解IOS单例的两种方式if(sharedSingletonManager==nil){

sharedSingletonManager=[superallocWithZone:zone];

returnsharedSingletonManager;//assignmentandreturnonfirstallocation

returnnil;//onsubsequentallocationattemptsreturnnil

-(id)copyWithZone:(NSZone*)zone

returnsharedSingletonManager;

-(id)retain

returnsharedSingletonManager;

-(NSUInteger)retainCount

returnUINT_MAX;//denotesanobjectthatcannotbereleased

-(onewayvoid)release

//donothing

-(id)autorelease

returnsharedSingletonManager;

//单例函数结束

方法二：

.h文件

#importFoundation/Foundation.h

@interfaceRtTestDataModel:NSObject

NSMutableArray*_buyDataTArray;

NSMutableArray*_sellDataTArray;

+(RtTestDataModel*)sharedManager;

-(void)addOptionBuyDataArrayModel:(NSMutableArray*)DataArray;

-(NSMutableArray*)getOptionBuyDataArrayModel;

@end

.m文件

#importRtTestDataModel.h

@implementationRtTestDataModel

+(RtTestDataModel*)sharedManager

staticRtTestDataModel*sharedManager=nil;

staticdispatch_once_tpredicate;

dispatch_once(predicate,^{

sharedManager=[[RtTestDataModelalloc]init];

});

returnsharedManager;

-(void)dealloc

[_buyDataTArrayremoveAllObjects];

[_buyDataTArrayrelease];

[superdealloc];

-(id)init

self=[superinit];

if(self!=nil){

_buyDataTArray=[[NSMutableArrayalloc]initWithCapacity:8];

returnself;

-(void)addOptionBuyDataArrayModel:(NSMutableArray*)DataArray{

if(DataArray!=nil){

[_buyDataTArrayremoveAllObjects];

[_buyDataTArrayaddObjectsFromArray:DataArray