после поворота изображенияжесты пинч работают беспорядочно и могут изменить размер изображения до нуля, делая его невидимымссылка может исчезнуть когда-нибудь, поэтому вот код: ViewController.h
//
// ViewController.h
// ImageGestureDemo
//
// Created by ByteSlinger on 6/21/18.
// Copyright © 2018 ByteSlinger. All rights reserved.
//
#import <UIKit/UIKit.h>
NSString *APP_TITLE = @"Image Gesture Demo";
NSString *INTRO_ALERT = @"\nDrag, Pinch and Rotate the Image!"
"\n\nYou can also Drag, Pinch and Rotate the background image."
"\n\nDouble tap an image to reset it";
float touchRadius = 48; // max distance from corners to touch point
typedef NS_ENUM(NSInteger, DragType) {
DRAG_OFF,
DRAG_ON,
DRAG_CENTER,
DRAG_TOP,
DRAG_BOTTOM,
DRAG_LEFT,
DRAG_RIGHT,
DRAG_TOPLEFT,
DRAG_TOPRIGHT,
DRAG_BOTTOMLEFT,
DRAG_BOTTOMRIGHT
};
@interface ViewController : UIViewController <UIGestureRecognizerDelegate>
//callback to process gesture events
- (IBAction)handlePan:(UIPanGestureRecognizer *)recognizer;
- (IBAction)handlePinch:(UIPinchGestureRecognizer *)recognizer;
- (IBAction)handleRotate:(UIRotationGestureRecognizer *)recognizer;
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer;
@end
ViewController.m
//
// ViewController.m
// ImageGestureDemo
//
// This is a DEMO. It shows how to pan, pinch, rotate and drag/resize a UIImageView.
//
// There is a background image and a foreground image. Both images can be
// panned, pinched and rotated, but only the foreground image can be resized
// by dragging one of it's corners or it's sides.
//
// NOTE: Sure, much of this code could have been put into a subclass of UIView
// or UIImageView. But for simplicity and reference sake, all code and
// methods are in one place, this ViewController subclass. There is no
// error checking at all. App tested on an iPhone 6+ and an iPad gen3.
//
// Features:
// - allows an image to be resized with pan gesture by dragging corners and sides
// - background image can be modified (pan, pinch, rotate)
// - foreground image can be modified (pan, pinch, rotate, drag/resize)
// - all image manipulation done within gestures linked from storyboard
// - all finger touches on screen show with yellow circles
// - when dragging, the touch circles turn to red (so you know when gestures start)
// - double tap on foreground image resets it to original size and rotation
// - double tap on background resets it and also resets the foreground image
// - screen and image touch and size info displayed on screen
// - uses CGAffineTransform objects for image manipulation
// - uses UIGestureRecognizerStateBegan in gestures to save transforms (the secret sauce...)
//
// Known Issues:
// - when the image is rotated, determining if a touch is on a corner or side
// does not work for large rotations. Need to check touch points against
// non rotated view frame and adjust accordingly.
// - after rotations, pinch and resize can shrink image to invisibility despite
// code attempts to prevent it.
//
// Created by ByteSlinger on 6/21/18.
// Copyright © 2018 ByteSlinger. All rights reserved.
//
#import "ViewController.h"
@interface ViewController ()
@property (strong, nonatomic) IBOutlet UIImageView *backgroundImageView;
@property (strong, nonatomic) IBOutlet UIImageView *foregroundImageView;
@property (strong, nonatomic) IBOutlet UILabel *screenInfoLabel;
@property (strong, nonatomic) IBOutlet UILabel *touchInfoLabel;
@property (strong, nonatomic) IBOutlet UILabel *imageInfoLabel;
@property (strong, nonatomic) IBOutlet UILabel *backgroundInfoLabel;
@property (strong, nonatomic) IBOutlet UILabel *changeInfoLabel;
@property (strong, nonatomic) IBOutlet UITapGestureRecognizer *backgroundTapGesture;
@property (strong, nonatomic) IBOutlet UITapGestureRecognizer *foregroundTapGesture;
@end
@implementation ViewController
CGRect originalImageFrame;
CGRect originalBackgroundFrame;
CGAffineTransform originalImageTransform;
CGAffineTransform originalBackgroundTransform;
NSMutableArray* touchCircles = nil;
DragType currentDragType = DRAG_OFF;
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
// set this to whatever your desired touch radius is
touchRadius = 48;
// In Storyboard this must have set to 1, then this seems to work ok
// when setting the double tap here
_foregroundTapGesture.numberOfTapsRequired = 2;
_backgroundTapGesture.numberOfTapsRequired = 2;
[self centerImageView:_foregroundImageView];
originalImageFrame = _foregroundImageView.frame;
originalBackgroundFrame = _backgroundImageView.frame;
originalImageTransform = _foregroundImageView.transform;
originalBackgroundTransform = _backgroundImageView.transform;
_backgroundImageView.contentMode = UIViewContentModeCenter;
_foregroundImageView.contentMode = UIViewContentModeScaleToFill; // allow stretch
[_backgroundImageView setUserInteractionEnabled:YES];
[_backgroundImageView setMultipleTouchEnabled:YES];
[_foregroundImageView setUserInteractionEnabled:YES];
[_foregroundImageView setMultipleTouchEnabled:YES];
[[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
[[NSNotificationCenter defaultCenter]
addObserver:self selector:@selector(orientationChanged:)
name:UIDeviceOrientationDidChangeNotification
object:[UIDevice currentDevice]];
[_touchInfoLabel setText:nil];
[_changeInfoLabel setText:nil];
[_imageInfoLabel setText:nil];
[_backgroundInfoLabel setText:nil];
touchCircles = [[NSMutableArray alloc] init];
}
- (void)viewDidAppear:(BOOL)animated {
[self alert:APP_TITLE :INTRO_ALERT];
}
- (void) orientationChanged:(NSNotification *)note
{
UIDevice * device = note.object;
switch(device.orientation)
{
case UIDeviceOrientationPortrait:
/* start special animation */
break;
case UIDeviceOrientationPortraitUpsideDown:
/* start special animation */
break;
default:
break;
};
[_screenInfoLabel setText:[NSString stringWithFormat:@"Screen: %.0f/%.0f",
self.view.frame.size.width,self.view.frame.size.height]];
}
//
// Update the info labels from the passed objects
//
- (void) updateInfo:(UIView *)imageView touch:(CGPoint)touch change:(CGPoint)change {
NSString *label;
UILabel *infoLabel;
if (imageView == _foregroundImageView) {
label = @"Image: %0.f/%0.f, %0.f/%0.f";
infoLabel = _imageInfoLabel;
} else {
label = @"Background: %0.f/%0.f, %0.f/%0.f";
infoLabel = _backgroundInfoLabel;
}
[infoLabel setText:[NSString stringWithFormat:label,
imageView.layer.frame.origin.x,
imageView.layer.frame.origin.y,
imageView.layer.frame.size.width,
imageView.layer.frame.size.height]];
[_touchInfoLabel setText:[NSString stringWithFormat:@"Touch: %0.f/%.0f",
touch.x,touch.y]];
[_changeInfoLabel setText:[NSString stringWithFormat:@"Change: %0.f/%.0f",
change.x,change.y]];
}
//
// Center the passed image frame within it's bounds
//
- (void)centerImageView:(UIImageView *)imageView {
CGSize boundsSize = self.view.bounds.size;
CGRect frameToCenter = imageView.frame;
// center horizontally
if (frameToCenter.size.width < boundsSize.width)
frameToCenter.origin.x = (boundsSize.width - frameToCenter.size.width) / 2;
else
frameToCenter.origin.x = 0;
// center vertically
if (frameToCenter.size.height < boundsSize.height)
frameToCenter.origin.y = (boundsSize.height - frameToCenter.size.height) / 2;
else
frameToCenter.origin.y = 0;
imageView.frame = frameToCenter;
}
//
// Remove all touch circles
//
- (void)removeTouchCircles {
[touchCircles makeObjectsPerformSelector: @selector(removeFromSuperview)];
[touchCircles removeAllObjects];
}
//
// Draw a circle around the passed point where the user has touched the screen
//
- (void)drawTouchCircle:(UIView *)view fromCenter:(CGPoint)point ofRadius:(float)radius {
CGRect frame = CGRectMake(point.x - view.frame.origin.x - radius,
point.y - view.frame.origin.y - radius,
radius * 2, radius * 2);
UIView *circle = [[UIView alloc] initWithFrame:frame];
circle.alpha = 0.5;
circle.layer.cornerRadius = radius;
circle.backgroundColor = currentDragType == DRAG_OFF ? [UIColor yellowColor] : [UIColor redColor];
[circle.layer setBorderWidth:1.0];
[circle.layer setBorderColor:[[UIColor blackColor]CGColor]];
[view addSubview:circle];
[touchCircles addObject:circle];
}
//
// Draw a touch circle for the passed user touch
//
- (void)handleTouchEvent:(UIView *) view
atPoint:(CGPoint) point
forState:(UIGestureRecognizerState) state
clear:(Boolean) clear {
//NSLog(@"handleTouchEvent");
if (clear) {
[self removeTouchCircles];
}
if (state == UIGestureRecognizerStateEnded) {
[self removeTouchCircles];
} else {
[self drawTouchCircle:self.view fromCenter:point ofRadius:touchRadius];
}
[_touchInfoLabel setText:[NSString stringWithFormat:@"Touch: %0.f/%.0f",
point.x,point.y]];
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
//NSLog(@"touchesBegan");
[self removeTouchCircles];
NSSet *allTouches = [event allTouches];
NSArray *allObjects = [allTouches allObjects];
for (int i = 0;i < [allObjects count];i++)
{
UITouch *touch = [allObjects objectAtIndex:i];
CGPoint location = [touch locationInView: self.view];
[self handleTouchEvent:touch.view atPoint:location forState:UIGestureRecognizerStateBegan clear:NO];
}
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
//NSLog(@"touchesMoved");
[self removeTouchCircles];
NSSet *allTouches = [event allTouches];
NSArray *allObjects = [allTouches allObjects];
for (int i = 0;i < [allObjects count];i++)
{
UITouch *touch = [allObjects objectAtIndex:i];
CGPoint location = [touch locationInView: self.view];
[self handleTouchEvent:touch.view atPoint:location forState:UIGestureRecognizerStateChanged clear:NO];
}
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
//NSLog(@"touchesEnded");
[self removeTouchCircles];
}
- (void)touchesCancelled:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event {
//NSLog(@"touchesCancelled");
[self removeTouchCircles];
}
//
// Double tap resets passed image. If background image, also reset foreground image.
//
- (IBAction)handleDoubleTap:(UITapGestureRecognizer *)recognizer {
CGPoint touch = [recognizer locationInView: self.view];
if (recognizer.state == UIGestureRecognizerStateBegan ||
recognizer.state == UIGestureRecognizerStateChanged) {
[self handleTouchEvent:recognizer.view atPoint:touch forState:recognizer.state clear:NO];
} else {
[self removeTouchCircles];
}
[self alert:@"Reset" :@"The Image has been Reset!"];
CGRect frame = originalImageFrame;
CGAffineTransform transform = originalImageTransform;
if (recognizer.view == _backgroundImageView) {
_foregroundImageView.transform = transform;
_foregroundImageView.frame = frame;
[self updateInfo:_foregroundImageView touch:touch change:CGPointZero];
frame = originalBackgroundFrame;
transform = originalBackgroundTransform;
}
recognizer.view.transform = transform;
recognizer.view.frame = frame;
[self updateInfo:recognizer.view touch:touch change:CGPointZero];
}
- (void) setDragType:(CGRect)frame withTouch:(CGPoint)touch {
// the corners and sides of the current view frame
CGRect topLeft = CGRectMake(frame.origin.x,frame.origin.y,
touchRadius, touchRadius);
CGRect bottomLeft = CGRectMake(frame.origin.x,
frame.origin.y + frame.size.height - touchRadius,
touchRadius, touchRadius);
CGRect topRight = CGRectMake(frame.origin.x + frame.size.width - touchRadius,
frame.origin.y,
touchRadius, touchRadius);
CGRect bottomRight = CGRectMake(frame.origin.x + frame.size.width - touchRadius,
frame.origin.y + frame.size.height - touchRadius,
touchRadius, touchRadius);
CGRect leftSide = CGRectMake(frame.origin.x,frame.origin.y,
touchRadius, frame.size.height);
CGRect rightSide = CGRectMake(frame.origin.x + frame.size.width - touchRadius,
frame.origin.y,
touchRadius, frame.size.height);
CGRect topSide = CGRectMake(frame.origin.x,frame.origin.y,
frame.size.width, touchRadius);
CGRect bottomSide = CGRectMake(frame.origin.x,
frame.origin.y + frame.size.height - touchRadius,
frame.size.width, touchRadius);
if (CGRectContainsPoint(topLeft, touch)) {
currentDragType = DRAG_TOPLEFT;
} else if (CGRectContainsPoint(topRight, touch)) {
currentDragType = DRAG_TOPRIGHT;
} else if (CGRectContainsPoint(bottomLeft, touch)) {
currentDragType = DRAG_BOTTOMLEFT;
} else if (CGRectContainsPoint(bottomRight, touch)) {
currentDragType = DRAG_BOTTOMRIGHT;
} else if (CGRectContainsPoint(topSide, touch)) {
currentDragType = DRAG_TOP;
} else if (CGRectContainsPoint(bottomSide, touch)) {
currentDragType = DRAG_BOTTOM;
} else if (CGRectContainsPoint(leftSide, touch)) {
currentDragType = DRAG_LEFT;
} else if (CGRectContainsPoint(rightSide, touch)) {
currentDragType = DRAG_RIGHT;
} else if (CGRectContainsPoint(frame, touch)) {
currentDragType = DRAG_CENTER;
} else {
currentDragType = DRAG_OFF; // touch point is not in the view frame
}
}
//
// Return the unrotated size of the view
//
- (CGSize) getActualSize:(UIView *)view {
CGSize result;
//CGSize originalSize = view.frame.size;
CGAffineTransform originalTransform = view.transform;
float rotation = atan2f(view.transform.b, view.transform.a);
// reverse rotation of current transform
CGAffineTransform unrotated = CGAffineTransformRotate(view.transform, -rotation);
view.transform = unrotated;
// get the size of the "unrotated" view
result = view.frame.size;
// reset back to what it was
view.transform = originalTransform;
//NSLog(@"Size current = %0.f/%0.f, rotation = %0.2f, unrotated = %0.f/%0.f",
// originalSize.width,originalSize.height,
// rotation,
// result.width,result.height);
return result;
}
//
// Resize or Pan an image on the ViewController View
//
- (IBAction)handleResize:(UIPanGestureRecognizer *)recognizer {
static CGRect initialFrame;
static CGAffineTransform initialTransform;
static Boolean scaleIt = YES;
// where the user has touched down
CGPoint touch = [recognizer locationInView: self.view];
//get the translation amount in x,y
CGPoint translation = [recognizer translationInView:recognizer.view];
if (recognizer.state == UIGestureRecognizerStateBegan)
{
initialFrame = recognizer.view.frame;
initialTransform = recognizer.view.transform;
[self setDragType:recognizer.view.frame withTouch:touch];
scaleIt = YES;
}
if (recognizer.state == UIGestureRecognizerStateEnded) {
currentDragType = DRAG_OFF;
scaleIt = NO;
[self getActualSize:recognizer.view];
} else {
// our new view frame - start with the initial one
CGRect newFrame = initialFrame;
// adjust the translation point according to where the user touched the image
float tx = translation.x;
float ty = translation.y;
// resize by dragging a corner or a side
if (currentDragType == DRAG_TOPLEFT) {
tx = -translation.x;
ty = -translation.y;
newFrame.origin.x += translation.x;
newFrame.origin.y += translation.y;
newFrame.size.width -= translation.x;
newFrame.size.height -= translation.y;
} else if (currentDragType == DRAG_TOPRIGHT) {
ty = -translation.y;
newFrame.origin.y += translation.y;
newFrame.size.width += translation.x;
newFrame.size.height -= translation.y;
} else if (currentDragType == DRAG_BOTTOMLEFT) {
tx = -translation.x;
newFrame.origin.x += translation.x;
newFrame.size.width -= translation.x;
newFrame.size.height += translation.y;
} else if (currentDragType == DRAG_BOTTOMRIGHT) {
// origin does not change
newFrame.size.width += translation.x;
newFrame.size.height += translation.y;
} else if (currentDragType == DRAG_TOP) {
tx = 0;
newFrame.origin.y += translation.y;
newFrame.size.height -= translation.y;
} else if (currentDragType == DRAG_BOTTOM) {
tx = 0;
newFrame.size.height += translation.y;
} else if (currentDragType == DRAG_LEFT) {
tx = -translation.x;
ty = 0;
newFrame.origin.x += translation.x;
newFrame.size.width -= translation.x;
} else if (currentDragType == DRAG_BOTTOM) {
ty = 0;
newFrame.size.width += translation.x;
} else { //if (currentDragType == DRAG_CENTER) {
newFrame.origin.x += translation.x;
newFrame.origin.y += translation.y;
scaleIt = NO; // normal pan
}
// get the unrotated size of the view
CGSize actualSize = [self getActualSize:recognizer.view];
// make sure we can still touch the image
if (actualSize.width < touchRadius * 2) {
newFrame.size.width += touchRadius * 2;
tx = 0; // stop resizing
}
if (actualSize.height < touchRadius * 2) {
newFrame.size.height += touchRadius * 2;
ty = 0; // stop resizing
}
// pan the image
recognizer.view.transform = CGAffineTransformTranslate(initialTransform, tx, ty);
if (scaleIt) {
// the origin or size changed
recognizer.view.frame = newFrame;
}
}
[self updateInfo:recognizer.view touch:touch change:translation];
}
//
// Pan an image on the ViewController View
//
- (IBAction)handlePan:(UIPanGestureRecognizer *)recognizer {
static CGAffineTransform initialTransform;
// where the user has touched down
CGPoint touch = [recognizer locationInView: self.view];
//get the translation amount in x,y
CGPoint translation = [recognizer translationInView:recognizer.view];
if (recognizer.state == UIGestureRecognizerStateBegan)
{
initialTransform = recognizer.view.transform;
currentDragType = DRAG_ON;
} else if (recognizer.state == UIGestureRecognizerStateEnded) {
currentDragType = DRAG_OFF;
[self getActualSize:recognizer.view];
}
recognizer.view.transform = CGAffineTransformTranslate(initialTransform, translation.x, translation.y);
[self updateInfo:recognizer.view touch:touch change:translation];
}
//
// Pinch (resize) an image on the ViewController View
//
- (void)handlePinch:(UIPinchGestureRecognizer *)recognizer {
static CGSize initialSize;
static CGAffineTransform initialTransform;
// where the user has touched down
CGPoint touch = [recognizer locationInView: self.view];
//get the translation amount in x,y
CGPoint change = CGPointMake(recognizer.view.transform.tx, recognizer.view.transform.ty);
if (recognizer.state == UIGestureRecognizerStateBegan)
{
initialSize = recognizer.view.frame.size;
initialTransform = recognizer.view.transform;
currentDragType = DRAG_ON;
} else if (recognizer.state == UIGestureRecognizerStateEnded) {
currentDragType = DRAG_OFF;
[self getActualSize:recognizer.view];
}
// make sure it stays visible
float scale = recognizer.scale;
float newWidth = initialSize.width * scale;
float newHeight = initialSize.height * scale;
// make sure we can still touch it
if (newWidth > touchRadius * 2 && newHeight > touchRadius * 2) {
// scale the image
recognizer.view.transform = CGAffineTransformScale(initialTransform, scale, scale);
}
[self updateInfo:recognizer.view touch:touch change:change];
}
//
// Rotate an image on the ViewController View
//
- (IBAction)handleRotate:(UIRotationGestureRecognizer *)recognizer {
static CGFloat initialRotation;
static CGAffineTransform initialTransform;
// where the user has touched down
CGPoint touch = [recognizer locationInView: self.view];
if (recognizer.state == UIGestureRecognizerStateBegan)
{
initialTransform = recognizer.view.transform;
initialRotation = atan2f(recognizer.view.transform.b, recognizer.view.transform.a);
currentDragType = DRAG_ON;
} else if (recognizer.state == UIGestureRecognizerStateEnded) {
currentDragType = DRAG_OFF;
[self getActualSize:recognizer.view];
}
recognizer.view.transform = CGAffineTransformRotate(initialTransform, recognizer.rotation);
[self updateInfo:recognizer.view touch:touch change:CGPointMake(initialRotation, recognizer.rotation)];
}
//
// Prevent simultaneous gestures so my transforms don't get funky
// (may not be necessary ... )
//
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
return NO;
}
//
// Spew a message to the user
//
- (void)alert:(NSString *) title :(NSString *)message {
UIAlertController *alert = [UIAlertController
alertControllerWithTitle: title
message: message
preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *okButton = [UIAlertAction
actionWithTitle:@"Ok"
style:UIAlertActionStyleDefault
handler:^(UIAlertAction * action) {
}];
[alert addAction:okButton];
[self presentViewController:alert animated:YES completion:nil];
}
@end