无法沿关键路径设置视图动画

Question

我正在尝试使QueueBall遵循路径。但是，当它第一次启动时，它会偏离路径并扭曲形状。一旦到达第三点，它便正确地遵循了路径。

有什么建议吗？

这似乎仅在我更改Main.Storyboard中的自动调整大小以适合全长和高度时才会发生。但仅适用于最初的开始。到达第3点后，它可以完美运行。

这是我正在使用的代码：

-(void)startEX1{
    viewQueuBall.frame = viewP1.frame;

    [UIView animateKeyframesWithDuration:animationSpeed delay:0.0 options:UIViewKeyframeAnimationOptionAllowUserInteraction animations:^{
        [UIView addKeyframeWithRelativeStartTime:0.0 relativeDuration:0.5 animations:^{
            viewQueuBall.frame = viewP2.frame;
        }];

        [UIView addKeyframeWithRelativeStartTime:0.5 relativeDuration:1.0 animations:^{
            viewQueuBall.frame = viewP3.frame;
        }];
    }completion:^(BOOL finished) {
        [self startEX2];
    }];
}

-(void)startEX2{
    viewQueuBall.frame = viewP3.frame;

    [UIView animateKeyframesWithDuration:animationSpeed delay:0.0 options:UIViewKeyframeAnimationOptionAllowUserInteraction animations:^{
        [UIView addKeyframeWithRelativeStartTime:0.0 relativeDuration:0.5 animations:^{
            viewQueuBall.frame = viewP4.frame;
        }];

        [UIView addKeyframeWithRelativeStartTime:0.5 relativeDuration:1.0 animations:^{
            viewQueuBall.frame = viewP1.frame;
        }];
    }completion:^(BOOL finished) {
        stepCount++;

        NSLog(@"Step Count = %i", stepCount);
        NSLog(@"Animation Speed = %f", animationSpeed);

        if (stepCount > 5) {
            [self performSegueWithIdentifier:kSegueGameCompleted sender:self];
            return;
        }

        if (stepCount == 2) {
            animationSpeed = 2.0;
        }else if (stepCount == 3){
            animationSpeed = 1.5;
        }else if (stepCount == 4){
            animationSpeed = 1.0;
        }

        [self startEX1];
    }];
}