Question

我想对UIImageView缩放进行2次操作，旋转，我有2个问题：

A。我为ex做了缩放操作。当我尝试进行旋转时，UIImageView设置为初始大小，我想知道如何保持缩放UIImageView并从缩放图像进行旋转。

B。我想将缩放操作与旋转相结合，我不知道如何实现这一点：

- (void)viewDidLoad 
{
    foo = [[UIImageView alloc]initWithFrame:CGRectMake(100.0, 100.0, 600, 800.0)];
    foo.userInteractionEnabled = YES;
    foo.multipleTouchEnabled  = YES;
    foo.image = [UIImage imageNamed:@"earth.jpg"];
    foo.contentMode = UIViewContentModeScaleAspectFit;
    foo.clipsToBounds = YES;

    [self.view addSubview:foo];
}

//---pinch gesture--- 
UIPinchGestureRecognizer *pinchGesture =
[[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(handlePinchGesture:)];
[foo addGestureRecognizer:pinchGesture]; 
[pinchGesture release];

//---rotate gesture--- 
UIRotationGestureRecognizer *rotateGesture =
[[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(handleRotateGesture:)];
[foo addGestureRecognizer:rotateGesture]; 
[rotateGesture release];

//---handle pinch gesture--- 
-(IBAction) handlePinchGesture:(UIGestureRecognizer *) sender {
    NSLog(@"Pinch");
    CGFloat factor = [(UIPinchGestureRecognizer *) sender scale];
    if (factor > 1) { 
        //---zooming in--- 
        sender.view.transform = CGAffineTransformMakeScale(
                                                           lastScaleFactor + (factor-1),
                                                           lastScaleFactor + (factor-1)); 
    } 
    else {
        //---zooming out--- 
        sender.view.transform = CGAffineTransformMakeScale(lastScaleFactor * factor, lastScaleFactor * factor);
    }
    if (sender.state == UIGestureRecognizerStateEnded) { 
        if (factor > 1) {
            lastScaleFactor += (factor-1); 
        } else {
            lastScaleFactor *= factor;
        }
    }
}

//---handle rotate gesture--- 
-(IBAction) handleRotateGesture:(UIGestureRecognizer *) sender {
    CGFloat rotation = [(UIRotationGestureRecognizer *) sender rotation]; 
    CGAffineTransform transform = CGAffineTransformMakeRotation(rotation + netRotation); 
    sender.view.transform = transform;
    if (sender.state == UIGestureRecognizerStateEnded) { 
        netRotation += rotation;
    }
}

由于

Answer 1

希望这对您有所帮助，这就是我通常实现手势识别器的方式：

UIRotationGestureRecognizer *rotationGesture = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(rotatePiece:)];
[piece addGestureRecognizer:rotationGesture];
[rotationGesture release];

UIPinchGestureRecognizer *pinchGesture = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(scalePiece:)];
[pinchGesture setDelegate:self];
[piece addGestureRecognizer:pinchGesture];
[pinchGesture release];

旋转方法：应用后将手势识别器的旋转重置为0，以便下一个回调是当前旋转的增量

- (void)rotatePiece:(UIRotationGestureRecognizer *)gestureRecognizer {
    [self adjustAnchorPointForGestureRecognizer:gestureRecognizer];

    if ([gestureRecognizer state] == UIGestureRecognizerStateBegan || [gestureRecognizer state] == UIGestureRecognizerStateChanged) {
        [gestureRecognizer view].transform = CGAffineTransformRotate([[gestureRecognizer view] transform], [gestureRecognizer rotation]);
        [gestureRecognizer setRotation:0];
    }
}

缩放方法，最后在应用后将手势识别器的比例重置为1，以便下一个回调是当前比例的增量

- (void)scalePiece:(UIPinchGestureRecognizer *)gestureRecognizer {
[self adjustAnchorPointForGestureRecognizer:gestureRecognizer];

    if ([gestureRecognizer state] == UIGestureRecognizerStateBegan || [gestureRecognizer state] == UIGestureRecognizerStateChanged) {
        [gestureRecognizer view].transform = CGAffineTransformScale([[gestureRecognizer view] transform], [gestureRecognizer scale], [gestureRecognizer scale]);
        [gestureRecognizer setScale:1];
    }
}

确保特定视图上的捏合，平移和旋转手势识别器可以同时识别，防止其他手势识别器同时识别

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
// if the gesture recognizers are on different views, don't allow simultaneous recognition
if (gestureRecognizer.view != otherGestureRecognizer.view)
    return NO;

// if either of the gesture recognizers is the long press, don't allow simultaneous recognition
if ([gestureRecognizer isKindOfClass:[UILongPressGestureRecognizer class]] || [otherGestureRecognizer isKindOfClass:[UILongPressGestureRecognizer class]])
    return NO;

    return YES;
}

相对于图层的锚点应用缩放和旋转变换此方法移动手势识别器的视图在用户手指之间的锚点

- (void)adjustAnchorPointForGestureRecognizer:(UIGestureRecognizer *)gestureRecognizer {
    if (gestureRecognizer.state == UIGestureRecognizerStateBegan) {
        UIView *piece = gestureRecognizer.view;
        CGPoint locationInView = [gestureRecognizer locationInView:piece];
        CGPoint locationInSuperview = [gestureRecognizer locationInView:piece.superview];

        piece.layer.anchorPoint = CGPointMake(locationInView.x / piece.bounds.size.width, locationInView.y / piece.bounds.size.height);
        piece.center = locationInSuperview;
    }
}

Answer 2

在代理中实施gestureRecognizer:shouldRecognizeSimultaneouslyWithGestureRecognizer:。

我设置了UIPinchGestureRecognizer，UIPanGestureRecognizer和UIRotationGestureRecognizer，我希望它们能同时运行。我还有一个UITapGestureRecognizer我不想要同时被识别。我所做的就是：

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
    if (![gestureRecognizer isKindOfClass:[UITapGestureRecognizer class]] && ![otherGestureRecognizer isKindOfClass:[UITapGestureRecognizer class]]) {
        return YES;
    }

    return NO;
}

Answer 3

我在斯坦福大学网站上找到了您可能感兴趣的内容：

http://www.stanford.edu/class/cs193p/cgi-bin/drupal/downloads-2010-winter

在此网站上，您需要向下滚动，直至看到数字14：“标题：第14讲 - MultiTouch”

下载：“14_MultiTouchDemo.zip”

在此示例中，您可以同时缩放和旋转每个图像。

希望我帮助过。）

Answer 4

当您使用CGAffineTransformMakeScale时，您每次使用它时都会重置Identity的转换，并且您将丢失先前的转换信息。

尝试使用CGAffineTransformScale(view.transform,scale, scale)进行缩放缩放。您需要保留原始帧大小以保持缩放控制见：How can I use pinch zoom(UIPinchGestureRecognizer) to change width of a UITextView?

同样轮换：

   if ([gestureRecognizer state] == UIGestureRecognizerStateBegan || [gestureRecognizer state] == UIGestureRecognizerStateChanged) {
        view.transform = CGAffineTransformRotate([view transform], [gestureRecognizer rotation]);
        [gestureRecognizer setRotation:0];
    }

Answer 5

我知道这是一个非常古老的线程，我遇到了这个imageview子类，它适用于缩放，旋转和平移。它在imageview上使用手势识别器。我将其用于我的应用程序之一。

ZoomRotatePanImageView

UIImageView手势（缩放，旋转）问题

5 个答案: