ios开发--旋转、移动、缩放手势实例代码

// 添加所有的手势
- (void) addGestureRecognizerToView:(UIView *)view
{
    // 旋转手势
    UIRotationGestureRecognizer *rotationGestureRecognizer = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(rotateView:)];
    [view addGestureRecognizer:rotationGestureRecognizer];

    // 缩放手势
    UIPinchGestureRecognizer *pinchGestureRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(pinchView:)];
    [view addGestureRecognizer:pinchGestureRecognizer];

    // 移动手势
    UIPanGestureRecognizer *panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(panView:)];
    [view addGestureRecognizer:panGestureRecognizer];
}

// 处理旋转手势
- (void) rotateView:(UIRotationGestureRecognizer *)rotationGestureRecognizer
{
    UIView *view = rotationGestureRecognizer.view;
    if (rotationGestureRecognizer.state == UIGestureRecognizerStateBegan || rotationGestureRecognizer.state == UIGestureRecognizerStateChanged) {
        view.transform = CGAffineTransformRotate(view.transform, rotationGestureRecognizer.rotation);
        [rotationGestureRecognizer setRotation:0];
    }
}

// 处理缩放手势
- (void) pinchView:(UIPinchGestureRecognizer *)pinchGestureRecognizer
{
    UIView *view = pinchGestureRecognizer.view;
    if (pinchGestureRecognizer.state == UIGestureRecognizerStateBegan || pinchGestureRecognizer.state == UIGestureRecognizerStateChanged) {
        view.transform = CGAffineTransformScale(view.transform, pinchGestureRecognizer.scale, pinchGestureRecognizer.scale);
        pinchGestureRecognizer.scale = 1;
    }
}

// 处理拖拉手势
- (void) panView:(UIPanGestureRecognizer *)panGestureRecognizer
{
    UIView *view = panGestureRecognizer.view;
    if (panGestureRecognizer.state == UIGestureRecognizerStateBegan || panGestureRecognizer.state == UIGestureRecognizerStateChanged) {
        CGPoint translation = [panGestureRecognizer translationInView:view.superview];
        [view setCenter:(CGPoint){view.center.x + translation.x, view.center.y + translation.y}];
        [panGestureRecognizer setTranslation:CGPointZero inView:view.superview];
    }
}