方法一：

网上用的很多的一种,不多说，直接上代码.

? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 -(void)startTime{ __block int timeout= 60; //倒计时时间 dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0); dispatch_source_t _timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0,queue); dispatch_source_set_timer(_timer,dispatch_walltime(NULL, 0),1.0*NSEC_PER_SEC, 0); //每秒执行 dispatch_source_set_event_handler(_timer, ^{ if(timeout<=0){ //倒计时结束，关闭 dispatch_source_cancel(_timer); dispatch_async(dispatch_get_main_queue(), ^{ [self.getIdentifyCodeBt setTitle:@"获取验证码" forState:UIControlStateNormal]; self.getIdentifyCodeBt.userInteractionEnabled = YES; [self.getIdentifyCodeBt setTitleColor:THEME_RED forState:UIControlStateNormal]; self.getIdentifyCodeBt.backgroundColor = [UIColor whiteColor]; self.getIdentifyCodeBt.layer.borderColor = THEME_RED.CGColor; }); }else{ dispatch_async(dispatch_get_main_queue(), ^{ [UIView beginAnimations:nil context:nil]; [UIView setAnimationDuration:1]; [self.getIdentifyCodeBt setTitle:[NSString stringWithFormat:@"%zd秒后失效",timeout] forState:UIControlStateNormal]; [self.getIdentifyCodeBt setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal]; self.getIdentifyCodeBt.backgroundColor = [UIColor lightGrayColor]; self.getIdentifyCodeBt.layer.borderColor = [UIColor clearColor].CGColor; self.getIdentifyCodeBt.clipsToBounds = YES; [UIView commitAnimations]; self.getIdentifyCodeBt.userInteractionEnabled = NO; }); timeout--; } }); dispatch_resume(_timer); }

到时直接调用就可以了。

方法二：利用分类

给UIButton新建一个分类

.h文件如下

? 1 2 3 4 5 6 #import <UIKit/UIKit.h> @interface UIButton (XSCountDown) - (void)xs_beginCountDownWithDuration:(NSTimeInterval)duration; - (void)xs_stopCountDown; @end

.m文件如下

? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 #import "UIButton+XSCountDown.h" #import "ThemeColor.h" static NSTimer *_countTimer; static NSTimeInterval _count; static NSString *_title; @implementation UIButton (XSCountDown) - (void)xs_beginCountDownWithDuration:(NSTimeInterval)duration { _title = self.titleLabel.text; _count = duration; _countTimer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(xs_updateTitle) userInfo:nil repeats:YES]; [[NSRunLoop mainRunLoop] addTimer:_countTimer forMode:NSRunLoopCommonModes]; self.userInteractionEnabled = NO; [self setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal]; self.backgroundColor = [UIColor lightGrayColor]; self.layer.borderColor = [UIColor clearColor].CGColor; self.clipsToBounds = YES; } - (void)xs_stopCountDown { [_countTimer invalidate]; _countTimer = nil; _count = 60.0; [self setTitle:_title forState:UIControlStateNormal]; self.userInteractionEnabled = YES; } - (void)xs_updateTitle { NSString *countString = [NSString stringWithFormat:@"%lis 后失效", (long)_count - 1]; self.userInteractionEnabled = NO; [self setTitle:countString forState:UIControlStateNormal]; if (_count-- <= 1.0) { [self xs_stopCountDown]; [self setTitleColor:THEME_RED forState:UIControlStateNormal]; self.backgroundColor = [UIColor whiteColor]; self.layer.borderColor = THEME_RED.CGColor; } } @end

然后在controller里直接调用分类.h文件里的方法就ok了

? 1 [self.verifyBt xs_beginCountDownWithDuration:60.0];

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持服务器之家。

原文链接：http://www.jianshu.com/p/08ed3cf8ec0c?utm_source=tuicool&utm_medium=referral