/**
 倒计时方法 在点击获取验证码按钮的方法里调用此方法即可实现, 需要在倒计时里修改按钮相关的请在此方法里yourButton修改
 */
- (void)sentPhoneCodeTimeMethod {
    //倒计时时间 - 60S
    __block NSInteger timeOut = 59;
    self.timeOut = timeOut;
    //执行队列
    dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
    //计时器 -》 dispatch_source_set_timer自动生成
    dispatch_source_t timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, queue);
    dispatch_source_set_timer(timer, DISPATCH_TIME_NOW, 1.0 * NSEC_PER_SEC, 0 * NSEC_PER_SEC);
    dispatch_source_set_event_handler(timer, ^{
        if (timeOut <= 0) {
            dispatch_source_cancel(timer);
            //主线程设置按钮样式
            dispatch_async(dispatch_get_main_queue(), ^{
                // 倒计时结束
                [yourButton setTitle:@"重发验证码" forState:UIControlStateNormal];
                [yourButton setTitleColor:[UIColor yourColor] forState:UIControlStateNormal];
                [yourButton setEnabled:YES];
                [yourButton setUserInteractionEnabled:YES];
            });
        } else {
            //开始计时
            //剩余秒数 seconds
            NSInteger seconds = timeOut % 60;
            NSString *strTime = [NSString stringWithFormat:@"%.1ld", seconds];
            //主线程设置按钮样式
            dispatch_async(dispatch_get_main_queue(), ^{
                [UIView beginAnimations:nil context:nil];
                [UIView setAnimationDuration:1.0];
                NSString *title = [NSString stringWithFormat:@"%@",strTime];
                [yourButton setTitle:title forState:UIControlStateNormal];
//              [yourButton.titleLabel setTextAlignment:NSTextAlignmentRight];
                // 设置按钮title居中 上面注释的方法无效
                [yourButton setContentHorizontalAlignment:UIControlContentHorizontalAlignmentCenter];
                [yourButton setTitleColor:[UIColor lightGrayColor] forState:UIControlStateNormal];
                [UIView commitAnimations];
                //计时器间不允许点击
                [yourButton setUserInteractionEnabled:NO];
            });
            timeOut--;
        }
    });
    dispatch_resume(timer);
}

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