先上图:
OK!今天要实现的就是发送验证码的倒计时。
首先搭建好你需要的页面。给“发送验证码”sendBtn添加一个方法。
[_sendBtn addTarget:self action:@selector(startTime:) forControlEvents:UIControlEventTouchUpInside];
接下来我们就来实现倒计时
- (void)startTime:(UIButton *)_b {
__block int timeout = 60;
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(), ^{
//设置界面的按钮显示 根据自己需求设置
[self.btn setTitle:@"发送验证码" forState:UIControlStateNormal];
self.btn.backgroundColor = COLORWITH_RGB(82, 158, 204);
self.btn.userInteractionEnabled = YES;
});
}else{
// int minutes = timeout / 60;
int seconds = timeout % 61;
NSString *strTime = [NSString stringWithFormat:@"%.2d秒后重发", seconds];
dispatch_async(dispatch_get_main_queue(), ^{
//设置界面的按钮显示 根据自己需求设置
//NSLog(@"____%@",strTime);
//下面两个方法都要写上,不然会出现倒计时每一秒会闪一下的情况
self.btn.titleLabel.text = [NSString stringWithFormat:@"%@",strTime];
[self.btn setTitle:[NSString stringWithFormat:@"%@",strTime] forState:UIControlStateNormal];
self.btn.backgroundColor = [UIColor colorWithHex:0xdadade alpha:1];
self.btn.userInteractionEnabled = NO;
});
timeout--;
}
});
dispatch_resume(_timer);
}
好了功能就已经实现了很简单吧如有问题请留言一起讨论~