直接上代码
__blockinttimeout=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(), ^{
//可以根据自己的实际界面图进行更改
[self.SendMsgBtnsetTitle:@"发送验证码"forState:UIControlStateNormal];
self.SendMsgBtn.userInteractionEnabled = YES;
});
}else{
intseconds = timeout %61;
NSString*strTime = [NSStringstringWithFormat:@"%.2d", seconds];
dispatch_async(dispatch_get_main_queue(), ^{
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:1];
[self.SendMsgBtn setTitle:[NSString stringWithFormat:@"%@S",strTime] forState:UIControlStateNormal];
[UIView commitAnimations];
self.SendMsgBtn.userInteractionEnabled = NO;
});
timeout--;
}
});
dispatch_resume(_timer);
