ios随设备旋转拖放

Question

我使用以下代码（如下所示）在多个不同位置实现拖放操作，并且过去一直很适合我。

现在我有一个问题，也不知道为什么。 只要在按下按钮的情况下获得面向设备（或模拟器）的肖像，它就可以完美工作。 但是在其他三个方向中的任何一个方向上，当手指拖动视图时，一个方向便会移动，而“拖动”视图的方向便会不同。

如下所示，我记录了每次移动的翻译价值。 在原始方向上，当我从屏幕中间向左下角拖动时，翻译的值为：

-，+

如果我向左旋转，然后再做一次：

-，-

再次向左旋转：

+，-

再次向左旋转：

+，+

我完全不了解这里发生的情况，特别是因为此代码似乎在其他视图控制器中运行良好。

任何建议将不胜感激。

- (void) didMakePanGesture:(UIPanGestureRecognizer *)panGesture
{
    if (panGesture.state == UIGestureRecognizerStateBegan)
    {
        [self setDropTargetsCoordinates];                                                           // saves correct drop target & its coordinates
        dragViewStartLocation = receptiveClassificationImageView.center;                            // save center in case we have to snap back
        receptiveClassificationImageView.transform = CGAffineTransformMakeScale(0.40f, 0.40f);      // make the image smaller for dragging
        receptiveClassificationImageView.layer.cornerRadius = 12.0f;                                // we lose the rounded corners in the scaling; this to fix
    }
    else if (panGesture.state == UIGestureRecognizerStateChanged)
    {
        //
        //   Adjust the location of the dragged view whenever state changes
        //
        CGPoint translation = [panGesture translationInView:nil];
        CGAffineTransform transform = receptiveClassificationImageView.transform;
        transform.tx = translation.x;
        transform.ty = translation.y;
        receptiveClassificationImageView.transform = transform;
        NSLog(@"Translation=%f,%f" translation.x, translation.y);


    }
    else if (panGesture.state == UIGestureRecognizerStateEnded)
    {
        // do stuff when dropped   
    }

Answer 1

以防万一以后有人看到此问题，可以通过对上面的代码进行以下更改来解决此问题：

if (panGesture.state == UIGestureRecognizerStateBegan)
{
    [self setDropTargetsCoordinates];                                                           // saves correct drop target & its coordinates
    dragViewStartLocation = receptiveClassificationImageView.center;                            // save center in case we have to snap back
    **receptiveClassificationImageView.center = [panGesture locationInView:receptiveClassificationImageView.superview]; // re-center the view before scaling**
    receptiveClassificationImageView.transform = CGAffineTransformMakeScale(0.40f, 0.40f);      // make the image smaller for dragging
    receptiveClassificationImageView.layer.cornerRadius = 12.0f;                                // we lose the rounded corners in the scaling; this to fix
}
else if (panGesture.state == UIGestureRecognizerStateChanged)
{
    //
    //   Adjust the location of the dragged view whenever state changes
    //
    CGPoint translation = [panGesture translationInView:**self.view**];
    CGAffineTransform transform = receptiveClassificationImageView.transform;
    transform.tx = translation.x;
    transform.ty = translation.y;
    receptiveClassificationImageView.transform = transform;
}