IOS之NSThread

初始化：

1.动态方法

- (id)initWithTarget:(id)target selector:(SEL)selector object:(id)argument;

// 初始化线程
NSThread *thread = [[NSThread alloc] initWithTarget:self selector:@selector(run) object:nil];
// 设置线程的优先级(0.0 - 1.0，1.0最高级)
thread.threadPriority = 1;
// 开启线程
[thread start];

2.静态方法

+ (void)detachNewThreadSelector:(SEL)selector toTarget:(id)target withObject:(id)argument;

[NSThread detachNewThreadSelector:@selector(run) toTarget:self withObject:nil];
// 调用完毕后，会马上创建并开启新线程

3.隐式创建线程

[self performSelectorInBackground:@selector(run) withObject:nil];

获取当前线程

NSThread *current = [NSThread currentThread];

获取主线程

NSThread *main = [NSThread mainThread];

暂停当前线程

// 暂停2s
[NSThread sleepForTimeInterval:2];

// 或者
NSDate *date = [NSDate dateWithTimeInterval:2 sinceDate:[NSDate date]];
[NSThread sleepUntilDate:date];

线程间的通信

1.在指定线程上执行操作

[self performSelector:@selector(run) onThread:thread withObject:nil waitUntilDone:YES];

2.在主线程上执行操作

[self performSelectorOnMainThread:@selector(run) withObject:nil waitUntilDone:YES];

3.在当前线程执行操作

[self performSelector:@selector(run) withObject:nil];