NSThread的使用
No.1：NSThread創(chuàng)建線程
NSThread有三種創(chuàng)建方式：
- init方式
- detachNewThreadSelector創(chuàng)建好之后自動(dòng)啟動(dòng)
- performSelectorInBackground創(chuàng)建好之后也是直接啟動(dòng)
/** 方法一，需要start */
NSThread *thread1 = [[NSThread alloc] initWithTarget:self selector:@selector(doSomething1:) object:@"NSThread1"];
// 線程加入線程池等待CPU調(diào)度，時(shí)間很快，幾乎是立刻執(zhí)行
[thread1 start];
/** 方法二，創(chuàng)建好之后自動(dòng)啟動(dòng) */
[NSThread detachNewThreadSelector:@selector(doSomething2:) toTarget:self withObject:@"NSThread2"];
/** 方法三，隱式創(chuàng)建，直接啟動(dòng) */
[self performSelectorInBackground:@selector(doSomething3:) withObject:@"NSThread3"];
- (void)doSomething1:(NSObject *)object {
// 傳遞過來的參數(shù)
NSLog(@"%@",object);
NSLog(@"doSomething1：%@",[NSThread currentThread]);
}
- (void)doSomething2:(NSObject *)object {
NSLog(@"%@",object);
NSLog(@"doSomething2：%@",[NSThread currentThread]);
}
- (void)doSomething3:(NSObject *)object {
NSLog(@"%@",object);
NSLog(@"doSomething3：%@",[NSThread currentThread]);
}
No.2：NSThread的類方法
- 返回當(dāng)前線程
// 當(dāng)前線程
[NSThread currentThread];
NSLog(@"%@",[NSThread currentThread]);
// 如果number=1，則表示在主線程，否則是子線程
打印結(jié)果：{number = 1, name = main}
- 阻塞休眠
//休眠多久
[NSThread sleepForTimeInterval:5];
//休眠到指定時(shí)間
[NSThread sleepUntilDate:[NSDate date]];
- 類方法補(bǔ)充
//退出線程
[NSThread exit];
//判斷當(dāng)前線程是否為主線程
[NSThread isMainThread];
//判斷當(dāng)前線程是否是多線程
[NSThread isMultiThreaded];
//主線程的對(duì)象
NSThread *mainThread = [NSThread mainThread];
No.3：NSThread的一些屬性
//線程是否在執(zhí)行
thread.isExecuting;
//線程是否被取消
thread.isCancelled;
//線程是否完成
thread.isFinished;
//是否是主線程
thread.isMainThread;
//線程的優(yōu)先級(jí)，取值范圍0.0到1.0，默認(rèn)優(yōu)先級(jí)0.5，1.0表示最高優(yōu)先級(jí)，優(yōu)先級(jí)高，CPU調(diào)度的頻率高
thread.threadPriority;
