button设置不能连续点击

- (void)todoSomething:(id)sender

{

//在这里做按钮的想做的事情。

}

- (void)starButtonClicked:(id)sender

{

//先将未到时间执行前的任务取消。

[[self class] cancelPreviousPerformRequestsWithTarget:self selector:@selector(todoSomething:) object:sender];

[self performSelector:@selector(todoSomething:) withObject:sender afterDelay:0.2f];

}