ios多线程的几种创建方式

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
     
    //创建线程的第一种方式
    NSThread *thread = [[NSThread alloc] initWithTarget:self selector:@selector(run:) object:@"universe"];
    [thread start];
    [thread release];
     
     
    //创建线程的第二种方式，NSThread类方法
    [NSThread detachNewThreadSelector:@selector(run:) toTarget:self withObject:@"yuzhou"];
     
     
    //创建线程的第三种方法  NSObject方法
    [self performSelectorInBackground:@selector(run:) withObject:@"nsobject thread"];
     
    //创建线程的第四种方式
    NSOperationQueue *oprationQueue = [[NSOperationQueue alloc] init];
    [oprationQueue addOperationWithBlock:^{
        //这个block语句块在子线程中执行
        NSLog(@"oprationQueue");
    }];
    [oprationQueue release];
     
    //第五种创建线程的方式
    NSOperationQueue *oprationQueue1 = [[NSOperationQueue alloc] init];
    oprationQueue1.maxConcurrentOperationCount = 1;//指定池子的并发数
     
    //NSOperation 相当于java中的runnable接口，继承自它的就相当一个任务
    NSInvocationOperation *invation = [[NSInvocationOperation alloc] initWithTarget:self selector:@selector(run:) object:@"invation"];
    [oprationQueue1 addOperation:invation];//将任务添加到池子里面，可以给池子添加多个任务，并且指定它的并发数
    [invation release];
     
    //第二个任务
    NSInvocationOperation *invation2 = [[NSInvocationOperation alloc] initWithTarget:self selector:@selector(run2:) object:@"invocation2"];
    invation2.queuePriority = NSOperationQueuePriorityHigh;//设置线程优先级
    [oprationQueue1 addOperation:invation2];
    [invation2 release];
     
    [oprationQueue1 release];
     
    //调用主线程，用来子线程和主线程交互,最后面的那个boolean参数，如果为yes就是等这个方法执行完了在执行后面的代码；如果为no的话，就是不管这个方法执行完了没有，接着往下走
    [self performSelectorOnMainThread:@selector(onMain) withObject:self waitUntilDone:YES];
     
    //---------------------GCD----------------------支持多核，高效率的多线程技术
    //创建多线程第六种方式
    dispatch_queue_t queue = dispatch_queue_create("name", NULL);
    //创建一个子线程
    dispatch_async(queue, ^{
        // 子线程code... ..
        NSLog(@"GCD多线程");
         
        //回到主线程
        dispatch_sync(dispatch_get_main_queue(), ^{//其实这个也是在子线程中执行的，只是把它放到了主线程的队列中
            Boolean isMain = [NSThread isMainThread];
            if (isMain) {
                NSLog(@"GCD主线程");
            }
        });
    });
     
     
    self.window.backgroundColor = [UIColor whiteColor];
    [self.window makeKeyAndVisible];
    return YES;
}
 
- (void)onMain
{
    Boolean b = [NSThread isMainThread];
    if (b) {
        NSLog(@"onMain;;%d",b);
    }
}
 
 
- (void) run:(NSString*)str
{
    NSLog(@"多线程运行:::%@",str);
}
- (void) run2:(NSString*)str
{
    NSLog(@"多线程运行:::%@",str);
}