UIImageView实现图片移动，缩放、旋转的代码片段

继承UIImageView，重写init函数。

//旋转手势
UIRotationGestureRecognizer *rotationGesture = [[UIRotationGestureRecognizer allor]initWithTarget:selft action:@selector(rotatePiece:)];
[self addGestureRecognizer:rotationGesture];
[rotationGesture release];

//放大缩小手势
UIPinchGestureRecognizer *pinchGesture = [[UIPinchGestureRecognizer alloc]initWithTarget:self action:@selector(scalePiece:)];
[pinchGesture setDelegate:self];
[self addGestureRecognizer:pinchGesture];
[pinchGesture release];

 

- (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;
    }
}

- (void)rotatePiece:(UIRotationGestureRecognizer *)gestureRecognizer
{
    [self adjustAnchorPointForGestureRecognizer:gestureRecognizer];
    
    if ([gestureRecognizer state] == UIGestureRecognizerStateBegan || [gestureRecognizer state] == UIGestureRecognizerStateChanged) {
        [gestureRecognizer view].transform = CGAffineTransformRotate([[gestureRecognizer view] transform], [gestureRecognizer rotation]);
        rotate = [gestureRecognizer rotation];
        isMoveState = NO;
        [gestureRecognizer setRotation:0];
    }
}

- (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]);
        scale = [gestureRecognizer scale];
        isMoveState = NO;
        [gestureRecognizer setScale:1];
    }
}

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
    if (gestureRecognizer.view != self.view)
        return NO;
    
    if (gestureRecognizer.view != otherGestureRecognizer.view)
        return NO;
    
    if ([gestureRecognizer isKindOfClass:[UILongPressGestureRecognizer class]] || [otherGestureRecognizer isKindOfClass:[UILongPressGestureRecognizer class]])
        return NO;
    
    return YES;
}

//移动方法，仍是继承UIImageView重写Touch
initialPoint为全局CGPoint

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {

    UITouch *touch = [touches anyObject];

    if ([touch tapCount] == 1)
    {
        CGPoint currentPoint = [touch locationInView:self];

        if (isOne)
        {
            initialPoint = currentPoint;
            isOne = NO;
        }
        CGFloat offsetX = currentPoint.x + self.frame.origin.x - initialPoint.x;
        CGFloat offsetY = currentPoint.y + self.frame.origin.y - initialPoint.y;
        self.frame = CGRectMake(offsetX, offsetY, self.frame.size.width, self.frame.size.height);
    }
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {

    initialPoint = CGPointMake(0, 0);
    isOne = YES;
}