ios - 如何等待几秒钟以确保在执行之前没有任何反应

Question

我有一个包含 2 个组件(列)的 UIPickerView，当用户完成选择时需要将其关闭。我希望它在 2 秒内等待用户消失。在这 2 秒内，如果用户执行任何选择，它将继续等待另外 2 秒。这是我的代码，让它在解雇前等待 2 秒。谢谢。

-(void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component{

    double delayInSeconds = 2; // number of seconds to wait
    dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, delayInSeconds * NSEC_PER_SEC);
    dispatch_after(popTime, dispatch_get_main_queue(), ^(void){

         [self.view endEditing:YES];
    });
}

Answer 1

NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:2.0 target:self selector:@selector(todo) userInfo:nil repeats:NO];

---

-(void) todo {
[self.view endEditing:YES];
}

阻止这一切

[timer invalidate];