时间倒计时和数字抽奖

- （void）viewdidload {
//延迟时间
_timeout = 10;
//调用方法
[self getcode];
}
//
- (void)getcode {

//__block int timeout= timecount; 
//倒计时时间
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
dispatch_source_t timercade = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0,queue);
dispatch_source_set_timer(timercade,dispatch_walltime(NULL, 0),0.1*NSEC_PER_SEC, 0); 
//每秒执行
dispatch_source_set_event_handler(timercade, ^{
if(_timeout<=1){ 
//倒计时结束，关闭
dispatch_source_cancel(timercade);
dispatch_async(dispatch_get_main_queue(), ^{
//设置界面的按钮显示 根据自己需求设置
});

}else{

//int seconds = timeout % 60;
//
dispatch_async(dispatch_get_main_queue(), ^{
//
[UIView beginAnimations:nil context:nil];
//
[UIView setAnimationDuration:0.1];
//随机数字
int randomVal=random() %10;
//赋值
NSString *strTime = [NSString stringWithFormat:@"%d", randomVal];
self.oneLabel.text = strTime;
int randomVal1=random() %10;
[UIView commitAnimations];
});
_timeout--;
}
});
dispatch_resume(timercade);

}