I had detected the two finger touch for imageview and given condition that if two finger is touched then pinchGesture have to perform the selector for imageview.
if ([[event allTouches]count] == 2)
{
imageView.multipleTouchEnabled=YES;
imageView.userInteractionEnabled =YES;
twoFingerPinch = [[UIPinchGestureRecognizer alloc]initWithTarget:self action:#selector(twoFingerPinch:)];
}
- (void)twoFingerPinch:(UIPinchGestureRecognizer *)recognizer
{
CGFloat scale = recognizer.scale;
imageView.transform = CGAffineTransformScale(imageView.transform, scale, scale);
recognizer.scale = 1.0;
}
But my twoFingerPinch method is not called. Anybody help me!! Thanks in advance.
As per your code it is hard to say on which view you want to apply pinch gesture,I am considering you are applying it on imageView, here is how you should do it:-
-(void)viewDidLoad
{
UIPinchGestureRecognizer * pinch = [[UIPinchGestureRecognizer alloc]initWithTarget:self action:#selector(twoFingerPinch:)];
[imageView addGestureRecognizer:pinch];
[imageView setUserInteractionEnabled:YES];
pinch.delegate = self;
}
- (void)twoFingerPinch:(UIPinchGestureRecognizer *)recognizer
{
CGFloat scale = recognizer.scale;
imageView.transform = CGAffineTransformScale(imageView.transform, scale, scale);
recognizer.scale = 1.0;
}
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
return NO;
}
Don't sure what are you trying to do, but if you want to pinch just add that directly to the view. Its default behavior for pinch to use 2 fingers.
Related
I am trying to do zoom-in and zoom-out in a UIView using UIPinchGestureRecognizer. But when I do pinch on my trackpad, it is not recognising the pinch and the control is not going to my twoFingerPinch function. I am using the following code.
- (void)viewDidLoad {
//.......
UIPinchGestureRecognizer *twoFingerPinch = [[UIPinchGestureRecognizer alloc]
initWithTarget:self
action:#selector(twoFingerPinch:)];
[myview addGestureRecognizer:twoFingerPinch];
//.....
}
- (void)twoFingerPinch:(UIPinchGestureRecognizer *)recognizer
{
NSLog(#"Pinch scale: %f", recognizer.scale);
if (recognizer.scale >1.0f && recognizer.scale < 2.5f) {
CGAffineTransform transform = CGAffineTransformMakeScale(recognizer.scale, recognizer.scale//);
myview.transform = transform;
}
}
Why it is not recognising the pinch from trackpad? Is there any other method to do the same?
First click on the Option button. you will get 2 gray spots which you can move using the mouse or trackpad. in older versions you need to press shift+option.
for more details check this.
Make sure that userInteractionEnabled is set to yes for your myview,
myview.userInteractionEnabled = YES;
I'm having issues figuring this out! All of the examples I have seen have to do with a scrollView and I am not using one. I need to crop an image within a predetermined CGRect area after the image has been manipulated through pinch, pan, and rotate. The code I have below crops the unmanipulated image in the upper left hand corner.
To Clarify pendantCanvasView is the view (container) and pendantImageView is a subclass of pendantCanvasView. PendantFrame is just a CGRect that has the coords of the rect in pendantImageView I want to crop.
Can someone help me?
Here is the code i have so far:
- (void)addMoveImageToolbox {
UIPinchGestureRecognizer *pinchRec = [[UIPinchGestureRecognizer alloc]initWithTarget:self action:#selector(handlePinch:)];
[self.pendantCanvasView addGestureRecognizer:pinchRec];
UIRotationGestureRecognizer *rotateRec = [[UIRotationGestureRecognizer alloc]initWithTarget:self action:#selector(handleRotate:)];
[self.pendantCanvasView addGestureRecognizer:rotateRec];
UIPanGestureRecognizer *panRec = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(handlePan:)];
[self.pendantCanvasView addGestureRecognizer:panRec];
}
- (void)handlePinch:(UIPinchGestureRecognizer*)pinch {
self.pendantImageView.transform = CGAffineTransformScale(self.pendantImageView.transform, pinch.scale, pinch.scale);
self.zoomScale = pinch.scale;
pinch.scale = 1;
}
- (void)handleRotate:(UIRotationGestureRecognizer*)rotate {
self.pendantImageView.transform = CGAffineTransformRotate(self.pendantImageView.transform, rotate.rotation);
rotate.rotation = 0;
}
- (void)handlePan:(UIPanGestureRecognizer *)pan {
CGPoint translation = [pan translationInView:self.pendantCanvasView];
self.pendantImageView.center = CGPointMake(self.pendantImageView.center.x + translation.x,
self.pendantImageView.center.y + translation.y);
[pan setTranslation:CGPointMake(0, 0) inView:self.pendantImageView];
}
Crop Method:
- (UIImage *)captureScreenInRect {
UIGraphicsBeginImageContextWithOptions(pendantFrame.size, NO, [UIScreen mainScreen].scale);
[self.pendantCanvasView drawViewHierarchyInRect:pendantFrame afterScreenUpdates:YES];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();self.pendantImageView.constraints
return image;
}
I believe drawViewHierarchyInRect re-renders the view hierarchy so it may be losing your alterations to the imageView.
you could try using snapshotViewAfterScreenUpdates instead.
I'm not sure what the relationships between pendantCanvasView, pendantImageView, and pendantFrame are but it may be possible to use the renderInContext method of the layer property of one or the other to get the cropped image.
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!!!
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);
}
}
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;
}
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];
}
note : this is how i have added this gesture to my imageview
UIPinchGestureRecognizer *pinchGesture = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:#selector(handlePinch:)];
pinchGesture.delegate=self;
[self.editPictureImageView addGestureRecognizer:pinchGesture];
note : this is my method that handles pinch transformation
mcurrentscale and mlastscale are of float type
-(void)handlePinch:(UIPinchGestureRecognizer*)sender {
mCurrentScale += [sender scale] - mLastScale;
mLastScale = [sender scale];
if (sender.state == UIGestureRecognizerStateEnded)
{
mLastScale = 1.0;
}
if (mCurrentScale < 1)
{
mCurrentScale = 1.0;
}
CGAffineTransform currentTransform = CGAffineTransformIdentity;
CGAffineTransform newTransform = CGAffineTransformScale(currentTransform, mCurrentScale, mCurrentScale);
self.editPictureImageView.transform = newTransform;
}
plzz help
This is probably a more awkward way to do it.
I would re-think your approach like so:
Add the UIImageView to a UIScrollView. The frame of the imageView should be the bounds of the scrollView, by which I mean at it's default position it the imageView should sit in the scrollView just like it did whilst it was sitting in a normal view.
Set up the UIScrollView (IB or code):
self.scrollView.delegate = self;
// example values
self.scrollView.minimumZoomScale = 0.4f;
self.scrolLView.maximumZoomScale = 3.0f;
Adopt this method:
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
{
// allow zooming of our image view
return self.imageView;
}
I want to scroll single image on touch like in angry birds.
can i use any gestures for scroll single image? And without using gestures how to scroll image?
Please help me.
Thank you.
You can use pinchgesturesrecognizer to scroll an image. here is code.
UIPinchGestureRecognizer *pinchGesture = [[UIPinchGestureRecognizer alloc]
initWithTarget:self action:#selector(scaleImage:)];
[self.view addGestureRecognizer:pinchGesture];
- (void)scaleImage:(UIPinchGestureRecognizer *)recognizer
{
if([recognizer state] == UIGestureRecognizerStateEnded) {
previousScale = 1.0;
return;
}
CGFloat newScale = 1.0 - (previousScale - [recognizer scale]);
CGAffineTransform currentTransformation = yourimage.transform;
CGAffineTransform newTransform = CGAffineTransformScale(currentTransformation, newScale, newScale);
yourimage.transform = newTransform;
previousScale = [recognizer scale];
}