Question

我有一个光标对象，我希望能够告诉它何时与nsbutton相交，以及它是否持续3秒。我的代码工作，除了当光标靠近按钮时，它会冻结直到它已经三秒钟，然后记录“按钮重叠3秒”。

   NSDate* date;
   -(BOOL)checkIfIntersects :(NSButton*)button {

      BOOL intersects =  CGRectIntersectsRect (cursor.frame,button.frame);

      if (intersects) {
         date = [NSDate date];

        while (intersects) {
            if ([date timeIntervalSinceNow] < -1)
            {
                NSLog(@"Button overlapped for 3 seconds");

                break;
            }
            intersects =  CGRectIntersectsRect (cursor.frame,button.frame);      
       }

    }

    return NO;

}

Answer 1

这是因为你的线程被卡在while(intersects)循环中，只有在满足内部if语句后退出。这会挂起你的整个帖子。

最快/最简单的解决方案是在您的功能之外加上NSDate。

  NSDate* momentIntersectionBegan = nil;
  BOOL intersectedPreviously = false;

  -(BOOL)checkIfIntersects :(NSButton*)button {
     BOOL currentlyIntersects =  CGRectIntersectsRect (cursor.frame,button.frame);

  if (currentlyIntersects) {
    if(intersectedPreviously){
        if ([momentIntersectionBegan timeIntervalSinceNow] < -3)
        {
            NSLog(@"Button overlapped for 3 seconds");
        }
    }else{
        momentIntersected = [NSDate date];
    }
      intersectedPreviously = true;
  }else{
      intersectedPreviously = false;
  } 

return NO;

}

检查nsbutton是否相交了一定的秒数

1 个答案: