Adding zoom in/out and crop for photo - ios

Question

I am trying to add capability to zoom in/out and crop a profile image before saving change but I am not sure how to go about this. Here below are my relevant codes:
- (void)viewDidLoad {
...
NSString *urlString = [User sharedUser].avatar;
NSURLRequest *imageRequest = [NSURLRequest requestWithURL:[NSURL URLWithString:urlString] cachePolicy:NSURLRequestReloadIgnoringLocalCacheData timeoutInterval:60];
[_avatarImageView setImageWithURLRequest:imageRequest placeholderImage:nil success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image) {
_avatarImageView.image = image;
} failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error) {
NSLog(#"Error: %#", error);
}];
_avatarImageView.layer.masksToBounds = YES;
_avatarImageView.layer.cornerRadius = _avatarImageView.frame.size.width / 2; //create circle image
[self initImagePicker];
...
}
- (void) initImagePicker {
myPicker = [[MyImagePicker alloc] init];
myPicker.SourceVC = self;
myPicker.SourceView = self.view;
myPicker.delegate = self;
myPicker.isImage = YES;
[myPicker initImagePicker];
}
- (IBAction) ChooseImageSourceAlbum {
tempType = POPUP_TYPE_IMAGPICKER;
selectArray = #[#"Camera",#"Choose Photos",#"Delete Photo"];
//Call popup
PopupTemplateViewController *vc = [[PopupTemplateViewController alloc] initWithNibName:#"PopupTemplateViewController" bundle:nil];
vc.delegate = self;
vc.dataArray = selectArray;
vc.type = POPUP_TYPE_OTHERS;
self.useBlurForPopup = NO;
[self presentPopupViewController:vc animated:YES completion:nil];
}
- (void) MyImagePickerTakePicture:(NSDictionary *)_dic {
NSString *mediaType = [_dic objectForKey:UIImagePickerControllerMediaType];
if ([mediaType isEqualToString:#"public.image"]) {
UIImage *image = [_dic objectForKey:UIImagePickerControllerOriginalImage];
//??? add crop and zoom image here!!!
[self performSelector:#selector(processImage:) withObject:image afterDelay:0.25f];
}
}
- ( void )processImage:( UIImage * )image {
CGFloat ratio = 1.0;
if (image.size.width > 400) {
ratio = 400 / image.size.width;
}
else if (image.size.height > 600) {
ratio = 600 / image.size.height;
}
UIImage *imageResize = [self scaleImage:image toScale:ratio];
[_avatarImageView setImage:imageResize];
[self UpdateAvatar];
}
- (UIImage *)scaleImage:(UIImage *)image toScale:(float)scaleSize{
UIGraphicsBeginImageContext(CGSizeMake(image.size.width * scaleSize, image.size.height * scaleSize));
[image drawInRect:CGRectMake(0, 0, image.size.width * scaleSize, image.size.height * scaleSize)];
UIImage *scaledImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return scaledImage;
}
- (void) UpdateAvatar {
[self showSeachingPopViewinView:self.view type:POPUP_TYPE_UPDATE];
NSString *account = [[User sharedUser] account];
NSMutableDictionary *parameters = [NSMutableDictionary new];
[parameters setObject:account forKey:#"account"];
[parameters setObject:_avatarImageView.image forKey:#"avatar"];
[GatewayManager callUpdateAvatar:parameters delegate:self];
}
- (void)popupView:(PopupTemplateViewController *)popupView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
[self dismissPopupViewControllerAnimated:NO completion:nil];
NSString *str = selectArray[indexPath.row];
if ([str isEqualToString:#"Camera"]) {
[myPicker OpenCamera];
}
else if ([str isEqualToString:#"Choose Photos"]) {
[myPicker OpenAlbum];
} else {
[self deletePhoto];
}
}
Now when I tab the profile image it will pop up view showing 3 choices: Camera, Choose Photo, Delete Photo. What I want to achieve is that after taking a photo or choosing a photo I want to have another view with the photo that I can zoom in/out and crop. Thanks in advance.

Answer 1

I found a property of image picker that allows editing, so I added this in init image picker:
imagePicker.allowsEditing = YES; //allows image to be editted before choosing
Also in MyImagePickerTakePicture I changed UIImagePickerControllerOriginalImage to UIImagePickerControllerEditedImage
- (void) MyImagePickerTakePicture:(NSDictionary *)_dic {
NSString *mediaType = [_dic objectForKey:UIImagePickerControllerMediaType];
if ([mediaType isEqualToString:#"public.image"]) {
UIImage *image = [_dic objectForKey:UIImagePickerControllerOriginalImage];
//??? add crop and zoom image here!!!
[self performSelector:#selector(processImage:) withObject:image afterDelay:0.25f];
}
}