自己动手实现一个队列LGQueue

iOS系统没有提供queue容器，如果想用，需要手动自己来写一个：

.h

//
//  LGQueue.h
//  AntsSportApp
//
//  Created by ligang on 15/3/24.
//  Copyright (c) 2015年 ligang. All rights reserved.
//

#import <Foundation/Foundation.h>

@interface LGQueue : NSObject

@property (nonatomic, strong) NSMutableArray *queue;

@property (nonatomic, readonly) NSInteger count;

- (void)enterQueue:(id)object;
- (id)exitQueue;
- (void)clear;

@end

.m

//
//  LGQueue.m
//  AntsSportApp
//
//  Created by ligang on 15/3/24.
//  Copyright (c) 2015年 ligang. All rights reserved.
//

#import "LGQueue.h"

@implementation LGQueue

- (id)init
{
    if ( self = [super init] ) {

        self.queue = [[NSMutableArray alloc] init];
        _count = 0;

    }
    return self;
}

- (void)enterQueue:(id)object
{
    [self.queue addObject:object];
    _count = self.queue.count;
}

- (id)exitQueue
{
    if ( self.queue.count == 0 )  return nil;

    id object = [self.queue objectAtIndex:0];
    [self.queue removeObjectAtIndex:0];
    _count = self.queue.count;

    return object;

}

- (void)clear
{
    [self.queue removeAllObjects];
    _count = 0;
}

@end

本文出处刚刚在线：http://www.superqq.com/blog/2015/03/24/zi-ji-dong-shou-chuang-jian-%5B%3F%5D-ge-dui-lie-lgqueue/