in Xcode 6, scale value from image diff with value in UIPinchGestureRecognizer - ios

Question

Now i develop an app that all user drag, rotate and scale image inside uiview. but when i want to save image view data like rotate value and scale value. i found scale value from [[img.layer valueForKeyPath:#"transform.scale"] floatValue] diff with scale that i found. the scale value is like below.
-(void)scale:(id)sender {
if([(UIPinchGestureRecognizer*)sender state] == UIGestureRecognizerStateBegan) {
_lastScale = 1.0;
}
CGFloat scale = 1.0 - (_lastScale - [(UIPinchGestureRecognizer*)sender scale]);
//CGFloat scale = 1.0 + ([(UIPinchGestureRecognizer *)sender scale] - _lastScale);
CGAffineTransform currentTransform = self.transform;
CGAffineTransform newTransform = CGAffineTransformScale(currentTransform, scale, scale);
[self setTransform:newTransform];
_lastScale = [(UIPinchGestureRecognizer*)sender scale];
CGFloat size = [[self.layer valueForKeyPath:#"transform.scale"] floatValue];
self.saveScale = _lastScale;
NSLog(#"Scale %f %f",_lastScale, size);
}
so the save scale value is diff with [[img.layer valueForKeyPath:#"transform.scale"].
PLEASE HELP!!!

Answer 1

Declare Variable -> CGFloat currentScale;
- (void) handlePinches:(UIPinchGestureRecognizer*)paramSender{
if (paramSender.state == UIGestureRecognizerStateEnded){
currentScale = paramSender.scale;
} else if (paramSender.state == UIGestureRecognizerStateBegan &&
self.currentScale != 0.0f){
paramSender.scale = currentScale;
}
if (paramSender.scale != NAN &&
paramSender.scale != 0.0){
paramSender.view.transform =
CGAffineTransformMakeScale(paramSender.scale,
paramSender.scale);
}
}

Answer 2

try this
You need to add Delegate
#interface MyClass : MySuperClass <UIGestureRecognizerDelegate>
- (void)viewDidLoad
{
[super viewDidLoad];
// set up the image view
UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"someImage"]];
[imageView setBounds:CGRectMake(0.0, 0.0, 120.0, 120.0)];
[imageView setCenter:self.view.center];
[imageView setUserInteractionEnabled:YES]; // <--- This is very important
// create and configure the pinch gesture
UIPinchGestureRecognizer *pinchGestureRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:#selector(pinchGestureDetected:)];
[pinchGestureRecognizer setDelegate:self];
[imageView addGestureRecognizer:pinchGestureRecognizer];
// create and configure the rotation gesture
UIRotationGestureRecognizer *rotationGestureRecognizer = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:#selector(rotationGestureDetected:)];
[rotationGestureRecognizer setDelegate:self];
[imageView addGestureRecognizer:rotationGestureRecognizer];
[self.view addSubview:imageView]; // add the image view as a subview of the view controllers view
}
add this two methods
- (void)pinchGestureDetected:(UIPinchGestureRecognizer *)recognizer
{
UIGestureRecognizerState state = [recognizer state];
if (state == UIGestureRecognizerStateBegan || state == UIGestureRecognizerStateChanged)
{
CGFloat scale = [recognizer scale];
[recognizer.view setTransform:CGAffineTransformScale(recognizer.view.transform, scale, scale)];
[recognizer setScale:1.0];
}
}
- (void)rotationGestureDetected:(UIRotationGestureRecognizer *)recognizer
{
UIGestureRecognizerState state = [recognizer state];
if (state == UIGestureRecognizerStateBegan || state == UIGestureRecognizerStateChanged)
{
CGFloat rotation = [recognizer rotation];
[recognizer.view setTransform:CGAffineTransformRotate(recognizer.view.transform, rotation)];
[recognizer setRotation:0];
}
}
after add this delegate method
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
return YES;
}

Answer 3

you can handle also pangesture using this method.
add pan gesture in to image.
self.panResizeGesture = [[UIPanGestureRecognizer alloc]initWithTarget:self action:#selector(handlePanGestures:)];
imgPatSelect.userInteractionEnabled = YES;
[imgPatSelect addGestureRecognizer:self.panResizeGesture];
add this method to handle pan.
- (void) handlePanGestures:(UIPanGestureRecognizer*)recognizer{
CGPoint translation = [recognizer translationInView:self.view];
CGRect recognizerFrame = recognizer.view.frame;
recognizerFrame.origin.x += translation.x;
recognizerFrame.origin.y += translation.y;
// Check if UIImageView is completely inside its superView
if (CGRectContainsRect(self.view.bounds, recognizerFrame)) {
recognizer.view.frame = recognizerFrame;
}
// Else check if UIImageView is vertically and/or horizontally outside of its
// superView. If yes, then set UImageView's frame accordingly.
// This is required so that when user pans rapidly then it provides smooth translation.
else {
// Check vertically
if (recognizerFrame.origin.y < self.view.bounds.origin.y) {
recognizerFrame.origin.y = 0;
}
else if (recognizerFrame.origin.y + recognizerFrame.size.height > self.view.bounds.size.height) {
recognizerFrame.origin.y = self.view.bounds.size.height - recognizerFrame.size.height;
}
// Check horizantally
if (recognizerFrame.origin.x < self.view.bounds.origin.x) {
recognizerFrame.origin.x = 0;
}
else if (recognizerFrame.origin.x + recognizerFrame.size.width > self.view.bounds.size.width) {
recognizerFrame.origin.x = self.view.bounds.size.width - recognizerFrame.size.width;
}
}
// Reset translation so that on next pan recognition
// we get correct translation value
[recognizer setTranslation:CGPointMake(0, 0) inView:self.view];
}