iphone - 如何在UILabel iPhone sdk中提供跑马灯效果？

Question

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Answer 1

我不太确定，但我认为你必须按帧制作动画。当你设置标签的坐标时，放置像 x,y 这样的变量而不是参数 1 和 2 的值。 并将其放入动画计时器中，并更改 x 和 y 的值。

类似的代码，它用于图像，您也可以对标签执行此操作:-

// Build array of images, cycling through image names
  for (int i = 0; i < IMAGE_COUNT; i++)
    [imageArray addObject:[UIImage imageNamed:[NSString stringWithFormat:@"Frame_%d.jpg", i]]];

  // Animated images - centered on screen
  animatedImages = [[UIImageView alloc] 
     initWithFrame:CGRectMake(
        (SCREEN_WIDTH / 2) - (IMAGE_WIDTH / 2), 
        (SCREEN_HEIGHT / 2) - (IMAGE_HEIGHT / 2) + STATUS_BAR_HEIGHT,
        IMAGE_WIDTH, IMAGE_HEIGHT)];
  animatedImages.animationImages = [NSArray arrayWithArray:imageArray];

  // One cycle through all the images takes 1.5 seconds
  animatedImages.animationDuration = 1.0;

  // Repeat forever
  animatedImages.animationRepeatCount = -1;

  // Add subview and make window visible
  [window addSubview:animatedImages];
  [window makeKeyAndVisible];

  // Start it up
  animatedImages.startAnimating;

  // Wait 5 seconds, then stop animation
    [self performSelector:@selector(stopAnimation) withObject:nil afterDelay:1000];

希望对你有帮助..:)