iOS多线程应用开发中自定义NSOperation类的实例解析

//

 

#import "YYViewController.h"
#import "YYappModel.h"
#import "YYdownLoadOperation.h"

@interface YYViewController ()<YYdownLoadOperationDelegate>
@property(nonatomic,strong)NSArray *apps;
@property(nonatomic,strong)NSOperationQueue *queue;

@end

复制代码
@implementation YYViewController
#pragma mark- 懒加载apps
-(NSArray *)apps
{
    if (_apps==nil) {
        NSString *path=[[NSBundle mainBundle]pathForResource:@"apps.plist" ofType:nil];
        NSArray *tempArray=[NSArray arrayWithContentsOfFile:path];
        
        //字典转模型
        NSMutableArray *array=[NSMutableArray array];
        for (NSDictionary *dict in tempArray) {
            YYappModel *app=[YYappModel appModelWithDict:dict];
            [array addObject:app];
        }
        _apps=array;
    }
    return _apps;
}

 

#pragma mark-懒加载queue
-(NSOperationQueue *)queue
{
    if (_queue==Nil) {
        _queue=[[NSOperationQueue alloc]init];
        //设置最大并发数为3
        _queue.maxConcurrentOperationCount=3;
    }
    return _queue;
}

#pragma mark-数据源方法
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return self.apps.count;
}
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *ID=@"ID";
    UITableViewCell *cell=[tableView dequeueReusableCellWithIdentifier:ID];
    if (cell==nil) {
        cell=[[UITableViewCell alloc]initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:ID];
    }
    YYappModel *app=self.apps[indexPath.row];