IOS Singleton Object

After long search , i have got the clear definition of iOS Singleton Object class, it nothing and very simple ,it's a like global class or variable  in iOS

so if you used singleton class mean you can access value  globally or data any where or any controller

eg:
 i have set value as first view controller after i can access that value to any another controller. with out passing data between view controller.

advantage:
memory
Easy flow
clear coding

Now i will tell u how to make singleton class

Step 1:
create nsobject class just like below

// File.h

#import <Foundation/Foundation.h>

@interface File : NSObject

{

    NSString *fileName;

}

@property(nonatomic,retain)NSString *fileName;

+ (File *)SharedInstance;

@end

// File.m

#import "File.h"

@implementation File

@synthesize fileName;

static File *file = nil;

+(File *)SharedInstance

{

    @synchronized(self)

    {

        if (file == nil) {

            file = [File new];

        }

    }

    return file;

}

@end

Then you can access value like below

 File *file =([File SharedInstance]);

    file.fileName = @"dhayaladevan";

    

    NSLog(@"%@",file.fileName);

hope i explained well.