UIRotationGestureRecognizer on UIImageview

Question

How to rotate UIImageView with two fingure touch in iOS SDK..as I know this is very simple but because of I am new in this technology so cant understand...

How to use UIRotationGestureRecognizer to implement this...

Please help me to solve this problem...

Thanks.

What have you done so far? Have you read this guide: http://developer.apple.com/library/ios/#documentation/EventHandling/Conceptual/EventHandlingiPhoneOS/GestureRecognizers/GestureRecognizers.html#//apple_ref/doc/uid/TP40009541-CH6-SW1 — bandejapaisa, Jan 13 '12 at 15:56
you can refer following links, http://stackoverflow.com/questions/3448614/uiimageview-gestures-zoom-rotate-question, http://www.icodeblog.com/2010/10/14/working-with-uigesturerecognizers/ — rishi, Jan 13 '12 at 16:52

score 12 · Answer 1 · edited May 17 '12 at 22:41

Code this on view did load or the imageview create function : m_ctrlImgVwShowImage - your's imageview

UIRotationGestureRecognizer *rotationRecognizer = [[[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(rotate:)] autorelease];
    [rotationRecognizer setDelegate:self];
    [m_ctrlImgVwShowImage addGestureRecognizer:rotationRecognizer];

//lastRotation is a cgfloat member variable

-(void)rotate:(id)sender {
    if([(UIRotationGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded) {
        _lastRotation = 0.0;
        return;
    }

    CGFloat rotation = 0.0 - (_lastRotation - [(UIRotationGestureRecognizer*)sender rotation]);

    CGAffineTransform currentTransform = m_ctrlImgVwShowImage.transform;
    CGAffineTransform newTransform = CGAffineTransformRotate(currentTransform,rotation);

    [m_ctrlImgVwShowImage setTransform:newTransform];

    _lastRotation = [(UIRotationGestureRecognizer*)sender rotation];
}

UIRotationGestureRecognizer on UIImageview

1 Answers1