Ios 淡入/淡出2个标签无限循环在tableview中

我试图在无限循环中显示一个带有两个变化字符串（如横幅）的间歇标签。 第一个标签应该淡入。之后，它应该淡出，让第二个标签做同样的事情。然后无限次或长时间重复该序列。 标签位于UITableView的子类内

到目前为止，我试过：

- (UITableViewCell *) tableView: (UITableView *) tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
  ...
  // Inside a cell an at its own section of the tableview
  cell.label1.alpha = 1;

            [UIView beginAnimations:nil context:nil];

            [UIView setAnimationDuration:3];
            [UIView setAnimationCurve:UIViewAnimationCurveLinear];
            [UIView setAnimationRepeatCount:INFINITY];
            [cell.label1 setAlpha:0];
            [UIView setAnimationRepeatAutoreverses:YES];

            [UIView commitAnimations];

            cell.label2.alpha = 1;

            [UIView beginAnimations:nil context:nil];

            [UIView setAnimationDuration:3];
            [UIView setAnimationCurve:UIViewAnimationCurveLinear];
            [UIView setAnimationRepeatCount:INFINITY];
            [cell.label1 setAlpha:0];
            [UIView setAnimationRepeatAutoreverses:YES];

            [UIView commitAnimations];

...
}

这段代码工作正常，但效果不清楚，因为淡入标签1与淡出标签2交叉，这很奇怪。

---

那么，我如何在两个动画之间休息一下，才能清楚地看到褪色的标签呢？

谢谢@Paulw11的回答，现在它工作正常了，下面是我的代码和更改：

cell.label2.alpha = 0;
            cell.label1.alpha = 1;

            [UIView animateKeyframesWithDuration:15 delay:0.0 options:0 animations:^{
                [UIView addKeyframeWithRelativeStartTime:0.0 relativeDuration:0.25 animations:^{
                    cell.label1.alpha = 0;
                    cell.label2.alpha = 0;
                    [self.view layoutIfNeeded];
                }];
                [UIView addKeyframeWithRelativeStartTime:0.25 relativeDuration:0.25 animations:^{
                    cell.label1.alpha = 0;
                    cell.label2.alpha = 1;
                    [self.view layoutIfNeeded];
                }];
                [UIView addKeyframeWithRelativeStartTime:0.50 relativeDuration:0.25 animations:^{
                    cell.label1.alpha = 0;
                    cell.label2.alpha = 0;
                    [self.view layoutIfNeeded];
                }];
                [UIView addKeyframeWithRelativeStartTime:0.75 relativeDuration:0.25 animations:^{
                    cell.label1.alpha = 1;
                    cell.label2.alpha = 0;
                    [self.view layoutIfNeeded];
                }];

                [UIView setAnimationRepeatCount: 200];


            } completion:nil];

---

谢谢@Paulw11的回答，现在它可以正常工作了，下面是我的代码和更改：

cell.label2.alpha = 0;
            cell.label1.alpha = 1;

            [UIView animateKeyframesWithDuration:15 delay:0.0 options:0 animations:^{
                [UIView addKeyframeWithRelativeStartTime:0.0 relativeDuration:0.25 animations:^{
                    cell.label1.alpha = 0;
                    cell.label2.alpha = 0;
                    [self.view layoutIfNeeded];
                }];
                [UIView addKeyframeWithRelativeStartTime:0.25 relativeDuration:0.25 animations:^{
                    cell.label1.alpha = 0;
                    cell.label2.alpha = 1;
                    [self.view layoutIfNeeded];
                }];
                [UIView addKeyframeWithRelativeStartTime:0.50 relativeDuration:0.25 animations:^{
                    cell.label1.alpha = 0;
                    cell.label2.alpha = 0;
                    [self.view layoutIfNeeded];
                }];
                [UIView addKeyframeWithRelativeStartTime:0.75 relativeDuration:0.25 animations:^{
                    cell.label1.alpha = 1;
                    cell.label2.alpha = 0;
                    [self.view layoutIfNeeded];
                }];

                [UIView setAnimationRepeatCount: 200];


            } completion:nil];

使用关键帧动画使用关键帧动画