NSThread

使用NSThread开辟线程有两种方式：

（1）手动开启方式的创建：

NSThread *thread = [[NSThread alloc]initWithTarget:self selector:@selector(thread) object:@"thread"];
[thread start];//    开启线程

（2）自动开启方式的创建：

[NSThread detachNewThreadSelector:@selector(thread1:) toTarget:self withObject:@"thread1"];
- (void)thread1:(NSString *)sender{

    [NSThread currentThread];//获取到当前所在的信息

    NSThread *thread = [NSThread currentThread];

//    thread.name = @"我是子线程 ";

//    NSLog(@"%@",thread);

////  [NSThread isMainThread] 判断当前线程是否是主线程

//    BOOL isMainThread = [NSThread isMainThread];

////  [NSThread isMultiThreaded] 判断是否是多线程

//    BOOL isMUltiThread = [NSThread isMultiThreaded];

//    NSLog(@"%d，%d",isMainThread,isMUltiThread);

////    设置线程的优先级(0-1) setThreadPriority:

//    [NSThread setThreadPriority:1.0];

////  sleepForTimeInterval:让线程休眠

//    [NSThread sleepForTimeInterval:2];

//    从网络加载图片并将它转化为data类型的数据

NSData *data = [NSData dataWithContentsOfURL:[NSURL URLWithString:kUrl]];

image = [UIImage imageWithData:data];

//    waiUntilDone设为YES，意味着UI更新完才会做其它操作

[self performSelectorOnMainThread:@selector(updateUI:) withObject:image waitUntilDone:YES];

}