NSTimer用法总结

1、

////  ViewController.m//  001-nstimer////#import "ViewController.h"@interface ViewController (){    NSTimer * _timer1;    NSTimer * _timer2;    NSTimer * _timer3;    NSTimer * _timer4;    NSTimer * _timer5;}@end@implementation ViewController- (void)viewDidLoad {    [super viewDidLoad];    // Do any additional setup after loading the view, typically from a nib.    self.view.backgroundColor = [UIColor whiteColor];        /*     + (NSTimer *)timerWithTimeInterval:(NSTimeInterval)ti invocation:(NSInvocation *)invocation repeats:(BOOL)yesOrNo;     + (NSTimer *)scheduledTimerWithTimeInterval:(NSTimeInterval)ti invocation:(NSInvocation *)invocation repeats:(BOOL)yesOrNo;          + (NSTimer *)timerWithTimeInterval:(NSTimeInterval)ti target:(id)aTarget selector:(SEL)aSelector userInfo:(nullable id)userInfo repeats:(BOOL)yesOrNo;     + (NSTimer *)scheduledTimerWithTimeInterval:(NSTimeInterval)ti target:(id)aTarget selector:(SEL)aSelector userInfo:(nullable id)userInfo repeats:(BOOL)yesOrNo;          - (instancetype)initWithFireDate:(NSDate *)date interval:(NSTimeInterval)ti target:(id)t selector:(SEL)s userInfo:(nullable id)ui repeats:(BOOL)rep NS_DESIGNATED_INITIALIZER;     */        //   1、    /*        以timerWithTimeInterval开头的两个方法需要手动加入到循环池中，否则不会启动        以scheduledTimerWithTimeInterval开头的两个方法则不需要手动假如循环池        五个方法都会自动执行        NSInvocation可以直接调用某个对象的消息，并可以处理多参数或者有返回值的情况，这里不再详细说明        interval设置时间间隔或者可以理解为等待多少秒后执行        repeats：YES重复执行，NO只执行一次     */    NSInvocation * invocation1 = [NSInvocation invocationWithMethodSignature:[[self class] instanceMethodSignatureForSelector:@selector(output1)]];    [invocation1 setTarget:self];    [invocation1 setSelector:@selector(output1)];        _timer1 = [NSTimer timerWithTimeInterval:3 invocation:invocation1 repeats:YES];    //加入主循环池    [[NSRunLoop mainRunLoop] addTimer:_timer1 forMode:NSDefaultRunLoopMode];        //   2、    NSInvocation * invocation2 = [NSInvocation invocationWithMethodSignature:[[self class] instanceMethodSignatureForSelector:@selector(output2)]];    [invocation2 setTarget:self];    [invocation2 setSelector:@selector(output2)];        _timer2 = [NSTimer scheduledTimerWithTimeInterval:3 invocation:invocation2 repeats:YES];            //   3、    _timer3 = [NSTimer timerWithTimeInterval:3 target:self selector:@selector(output3) userInfo:nil repeats:YES];    //加入当前循环池    [[NSRunLoop currentRunLoop] addTimer:_timer3 forMode:NSDefaultRunLoopMode];    /*     如果当前runloop没有运行，则可以调用以下方法手动运行     - (void)run;     - (void)runUntilDate:(NSDate *)limitDate;     - (BOOL)runMode:(NSString *)mode beforeDate:(NSDate *)limitDate;     */            //   4、    _timer4 = [NSTimer scheduledTimerWithTimeInterval:3 target:self selector:@selector(output4) userInfo:nil repeats:YES];            //   5、    /*        这个会首先立即执行，有fireDate决定立即执行一次，然后每隔3秒执行一次，由输出也可以看出     */    NSDate * fireDate = [NSDate date];    _timer5 = [[NSTimer alloc] initWithFireDate:fireDate interval:3 target:self selector:@selector(output5) userInfo:nil repeats:YES];    [[NSRunLoop mainRunLoop] addTimer:_timer5 forMode:NSDefaultRunLoopMode];                UIButton * btn1 = [UIButton buttonWithType:UIButtonTypeCustom];    btn1.frame = CGRectMake(10, 50, 50, 50);    btn1.backgroundColor = [UIColor orangeColor];    [btn1 setTitle:@"start1" forState:UIControlStateNormal];    [btn1 addTarget:self action:@selector(start1:) forControlEvents:UIControlEventTouchUpInside];    [self.view addSubview:btn1];    }- (void) start1:(id) sender {        //首先判断定时器是否有效，如果有效，则让它无效，然后置为nil    if (_timer1.isValid) {        [_timer1 invalidate];    }    _timer1 = nil;    }- (void) output1 {    NSLog(@"output1");}- (void) output2 {    NSLog(@"output2");}- (void) output3 {    NSLog(@"output3");}- (void) output4 {    NSLog(@"output4");}- (void) output5 {    NSLog(@"output5");}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}@end

输出：

2016-02-16 12:50:37.328 001-nstimer[1802:63641] output52016-02-16 12:50:40.319 001-nstimer[1802:63641] output12016-02-16 12:50:40.320 001-nstimer[1802:63641] output22016-02-16 12:50:40.320 001-nstimer[1802:63641] output32016-02-16 12:50:40.321 001-nstimer[1802:63641] output42016-02-16 12:50:40.321 001-nstimer[1802:63641] output52016-02-16 12:50:43.320 001-nstimer[1802:63641] output12016-02-16 12:50:43.321 001-nstimer[1802:63641] output22016-02-16 12:50:43.321 001-nstimer[1802:63641] output32016-02-16 12:50:43.321 001-nstimer[1802:63641] output42016-02-16 12:50:43.322 001-nstimer[1802:63641] output5

2、成员变量

设置定时器的启动时间

@property (copy) NSDate *fireDate;

只读属性，获取定时器的调用时间间隔

@property (readonly) NSTimeInterval timeInterval;

7.0之后新增的数学，设置误差范围

@property NSTimeInterval tolerance NS_AVAILABLE(10_9, 7_0);

判断定时器是否有效
@property (readonly, getter=isValid) BOOL valid;

获取参数信息
@property (nullable, readonly, retain) id userInfo;