Singleton

#import <UIKit/UIKit.h>
 
 
@interface SingleTon : UIView {
    NSMutableString *xml;
    NSMutableString *xmlstring;
    
    
}
 
@property(nonatomic, retain) NSMutableString *xmlstring;
-(void)initiliazation;
+(SingleTon *)Instance;
-(NSString *)makeXml:(NSString *)param;

#import "SingleTon.h"
 
@implementation SingleTon
 
@synthesize xmlstring;
 
- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        // Initialization code
    }
    return self;
}
 
/*
// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect
{
    // Drawing code
}
*/
 
-(void)initiliazation
{
    [xmlstring setString:@"qwerty"];
}
 
static SingleTon * Instance = NULL;
    +(SingleTon *) Instance {
    if (!Instance || Instance == NULL) {
    Instance = [SingleTon new];
    }
    return Instance;
}
 
-(NSString *)makeXml:(NSString *)param
{
    // код ........
    return param;
}
 
 
- (void)dealloc
{   
    [xmlstring release];
    self.xmlstring = nil;
    [super dealloc];
}
 
@end

//Not ARC:
static SomeClass *instance = nil;
 
static void singleton_remover() {
    if (instance) {
        [instance release];
        instance = nil;
    }
}
 
+ (SomeClass*)sharedInstance {
    @synchronized (self) {
        if (!instance) {
            instance = [[SomeClass alloc] init];
            atexit(singleton_remover);
        }
        return instance;
    }
}

[NSAllocateObject([self class], 0, NULL) init]

+ (id) allocWithZone:(NSZone *)zone
{
  return [[self sharedInstance] retain];
}