NSThread多线程方式

#import "TableViewController.h"

@interface TableViewController ()

@end

@implementation TableViewController

- (void)viewDidLoad {
    [super viewDidLoad];    
    
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    return 100;
}


- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"cell" forIndexPath:indexPath];
    //NSThread 线程对象,轻量级的多线程方式
    //手动创建,手动启动线程
    NSThread *thread = [[NSThread alloc] initWithTarget:self selector:@selector(loopIn) object:nil];
    //执行
    [thread start];
    //取消,线程启动前可以取消,
    [thread cancel];
    
    //自动执行线程
//    [NSThread detachNewThreadSelector:@selector(loopIn) toTarget:self withObject:nil];
    
    return cell;
}
-(void)loopIn{
    
    //手动创建的子线程须添自动释放池,系统的子线程无需添加
    @autoreleasepool {
        //线程休眠(秒)
        [NSThread sleepForTimeInterval:1];
        
        //线程状态cancel/finish/excuting
        //获取当前线程,输出线程状态
        NSThread *currentThread = [NSThread currentThread];
        //当前线程是否取消
        NSLog(@"取消:%d",[currentThread isCancelled]);
        //当前线程是否结束
        NSLog(@"结束:%d",[currentThread isFinished]);
        //当前线程是否执行
        NSLog(@"执行:%d",[currentThread isExecuting]);
        for (int i = 0; i < 100; i++) {
            printf("%d",i);
            //线程退出,强制退出当前线程
            [NSThread exit];
        }
    }
    //线程休眠(秒)
    [NSThread sleepForTimeInterval:1];
    
    //线程状态cancel/finish/excuting
    //获取当前线程,输出线程状态
    NSThread *currentThread = [NSThread currentThread];
    //当前线程是否取消
    NSLog(@"取消:%d",[currentThread isCancelled]);
    //当前线程是否结束
    NSLog(@"结束:%d",[currentThread isFinished]);
    //当前线程是否执行
    NSLog(@"执行:%d",[currentThread isExecuting]);
    for (int i = 0; i < 100; i++) {
        printf("%d",i);
        //线程退出,强制退出当前线程
        [NSThread exit];
    }
    
}



@end

#import "ViewController.h"

@interface ViewController ()
@property (weak, nonatomic) IBOutlet UIImageView *imageView;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
}
//返回
- (IBAction)back:(UIButton *)sender {
    
    [self dismissViewControllerAnimated:YES completion:nil];
//下载
}
- (IBAction)download:(id)sender {
    //自动线程
    [NSThread detachNewThreadSelector:@selector(loadImage) toTarget:self withObject:nil];
    
    
}
//加载图片
-(void)loadImage
{
    NSURL *url = [NSURL URLWithString:@"http://b.hiphotos.baidu.com/zhidao/pic/item/a8ec8a13632762d01650d902a3ec08fa513dc625.jpg"];
    NSData *imgData = [NSData dataWithContentsOfURL:url];
    
    UIImage *image = [UIImage imageWithData:imgData];
    self.imageView.image = image;
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end