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如何在保持前一次旋转变换的同时进行变焦？

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我有一个imageView，我已经添加了UIPinchGestureRecognizer和UIRotationGestureRecognizer .

在捏手势，我变换和缩放视图和旋转手势我应用旋转变换 .

问题是我旋转imageView然后开始缩放 . 缩放总是从正常状态开始 .

所以我想要的是当我将它旋转到顺时针旋转30度然后缩放它 . 它应该在顺时针方向保持30度的同时进行变焦 .

Here is the code:

- (void)viewDidLoad{
    [super viewDidLoad];

//setting up the image view

mTotalRotation = 0.0;
self.imageView.image = self.photo;
self.imageView.userInteractionEnabled = YES;

UIRotationGestureRecognizer *twoFingersRotate = 
[[[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(twoFingersRotate:)] autorelease];
[self.imageView addGestureRecognizer:twoFingersRotate];

UIPinchGestureRecognizer *pinchGesture = [[[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(pinchZoom:)] autorelease];
[self.imageView addGestureRecognizer:pinchGesture];

// Do any additional setup after loading the view from its nib.
}
// Rotation gesture handler
- (void)twoFingersRotate:(UIRotationGestureRecognizer *)recognizer 
{


if ([recognizer state] == UIGestureRecognizerStateEnded) {

    mTotalRotation += recognizer.rotation;
    return;
}

self.imageView.transform = CGAffineTransformMakeRotation(mTotalRotation + recognizer.rotation);         


}


   // Pinch Gesture

   -(void)pinchZoom:(UIPinchGestureRecognizer*)recognizer{


    self.imageView.transform = CGAffineTransformMakeScale(recognizer.scale, recognizer.scale) ;



}
iphone ios uigesturerecognizer

2 回答

  • 4

    换行：

    self.imageView.transform = CGAffineTransformMakeRotation(mTotalRotation + recognizer.rotation);

    有：

    self.imageView.transform = CGAffineTransformRotate(self.imageView.transform, recognizer.rotation);

    和行：

    self.imageView.transform = CGAffineTransformMakeScale(recognizer.scale, recognizer.scale);

    有：

    self.imageView.transform = CGAffineTransformScale(self.imageView.transform, recognizer.scale, recognizer.scale);

    编辑

    要限制比例，您可以执行以下操作：

    CGAffineTransform transform = self.imageView.transform;
float newScale = recognizer.scale * sqrt(transform.a*transform.a + transform.c*transform.c);
if (newScale > scaleLimit) {
    self.imageView.transform = CGAffineTransformScale(transform, recognizer.scale, recognizer.scale);
}
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  • 0

    也许您可以将缩放和旋转视图作为缩放视图的子视图？

    回复于

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