How to increase or decrease the size of a UIImageView by dragging the right corner of the edge?

Question

I am making an application that has a function that resizes a UIImageView by dragging the right corner of the edge of the UIImageView, as it zooms in and out. Also we can rotate the image.

How can i achieve this?

Answer 1

If resizing a UIImage, use the SPUserResizableView following link.

For rotation, u will add a UIRotationGestureRecognizer to the resizableview.

Answer 2

Use this code. Here, images are selected from PhotoLibrary, and then using gestures that they move, scale, etc. I use all the gestures to help you do just about anything, like panning, pinching and rotating any image you put.

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info { [picker dismissModalViewControllerAnimated:YES]; imageCollage = [[UIImageView alloc]initWithFrame:CGRectMake(80, 80, 150, 150)]; [imageCollage setUserInteractionEnabled:YES]; imageCollage.image = [info objectForKey:UIImagePickerControllerOriginalImage]; holderView = [[UIView alloc] initWithFrame:CGRectMake(0,0,imageCollage.frame .size.width, imageCollage.frame.size.height)]; holderView.layer.cornerRadius = 6; holderView.clipsToBounds = YES; imageview = [[UIImageView alloc] initWithFrame:[holderView frame]]; [imageview setImage:imageCollage.image]; [holderView addSubview:imageview]; UIPinchGestureRecognizer *pinchRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(scale:)]; [pinchRecognizer setDelegate:self]; [holderView addGestureRecognizer:pinchRecognizer]; UIRotationGestureRecognizer *rotationRecognizer = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(rotate:)]; [rotationRecognizer setDelegate:self]; [holderView addGestureRecognizer:rotationRecognizer]; UIPanGestureRecognizer *panRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(move:)]; [panRecognizer setMinimumNumberOfTouches:1]; [panRecognizer setMaximumNumberOfTouches:1]; [panRecognizer setDelegate:self]; [holderView addGestureRecognizer:panRecognizer]; DeleteImage = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, 30, 30)]; [DeleteImage setImage:[UIImage imageNamed:@"DeleteRed.png"]]; [holderView addSubview:DeleteImage]; DeleteImage.userInteractionEnabled = YES; UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapped:)]; [tapRecognizer setNumberOfTapsRequired:1]; [tapRecognizer setDelegate:self]; [DeleteImage addGestureRecognizer:tapRecognizer]; [BaseView addSubview:holderView]; [Trash setImage:[UIImage imageNamed:@"12456977871712665073hrum_trash.svg.med.png"] forState:UIControlStateNormal]; } -(void)scale:(id)sender { BaseView.clipsToBounds = YES; [BaseView bringSubviewToFront:[(UIPinchGestureRecognizer*)sender view]]; if([(UIPinchGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded) { lastScale = 1.0; return; } CGFloat scale = 1.0 - (lastScale - [(UIPinchGestureRecognizer*)sender scale]); CGAffineTransform currentTransform = [(UIPinchGestureRecognizer*)sender view].transform; CGAffineTransform newTransform = CGAffineTransformScale(currentTransform, scale, scale); [[(UIPinchGestureRecognizer*)sender view] setTransform:newTransform]; lastScale = [(UIPinchGestureRecognizer*)sender scale]; } -(void)rotate:(id)sender { [BaseView bringSubviewToFront:[(UIRotationGestureRecognizer*)sender view]]; if([(UIRotationGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded) { lastRotation = 0.0; return; } CGFloat rotation = 0.0 - (lastRotation - [(UIRotationGestureRecognizer*)sender rotation]); CGAffineTransform currentTransform = [(UIPinchGestureRecognizer*)sender view].transform; CGAffineTransform newTransform = CGAffineTransformRotate(currentTransform,rotation); [[(UIRotationGestureRecognizer*)sender view] setTransform:newTransform]; lastRotation = [(UIRotationGestureRecognizer*)sender rotation]; } -(void)move:(id)sender { [[[(UITapGestureRecognizer*)sender view] layer] removeAllAnimations]; BaseView.clipsToBounds = YES; [BaseView bringSubviewToFront:[(UIPanGestureRecognizer*)sender view]]; CGPoint translatedPoint = [(UIPanGestureRecognizer*)sender translationInView:self.view]; if([(UIPanGestureRecognizer*)sender state] == UIGestureRecognizerStateBegan) { firstX = [[sender view] center].x; firstY = [[sender view] center].y; } translatedPoint = CGPointMake(firstX+translatedPoint.x, firstY+translatedPoint.y); [[sender view] setCenter:translatedPoint]; if([(UIPanGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded) { CGFloat finalX = translatedPoint.x + (.20*[(UIPanGestureRecognizer*)sender velocityInView:self.view].x); CGFloat finalY = translatedPoint.y + (.20*[(UIPanGestureRecognizer*)sender velocityInView:self.view].y); if(UIDeviceOrientationIsPortrait([[UIDevice currentDevice] orientation])) { if(finalX < 0) { finalX = 0; } else if(finalX > 260) { finalX = 260; } if(finalY < 0) { finalY = 0; } else if(finalY > 416) { finalY = 416; } } else { if(finalX < 0) { finalX = 0; } else if(finalX > 416) { finalX = 260; } if(finalY < 0) { finalY = 0; } else if(finalY > 260) { finalY = 416; } } [UIView beginAnimations:nil context:NULL]; [UIView setAnimationDuration:.35]; [UIView setAnimationCurve:UIViewAnimationCurveEaseOut]; [[sender view] setCenter:CGPointMake(finalX, finalY)]; [UIView commitAnimations]; } } -(void)tapped:(UIGestureRecognizer *)recogniser { NSLog(@"%@",recogniser.view); [Trash setImage:[UIImage imageNamed:@"trash_bin_recycle_quit_terminate_error_cancel_close_exit.png"] forState:UIControlStateNormal]; [[[recogniser view] superview] removeFromSuperview]; } - (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer { return ![gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]]; } 

Any inquiries about the code, please feel free to ask:) ... Happy Coding ..