Align UIImageView Center dynamically in xCode

Suppose we have an UIImageView with name imageView and have to set this in center dynamically then we can follow the below step

[imageView setImage:[UIImage imageNamed:@"imageName.png"]];

imageView.autoresizingMask = UIViewAutoresizingNone;

imageView.contentMode = UIViewContentModeCenter;

CREATION OF IMAGE VIEW IN CIRCLE

Creation of image like below.
 
1. Take an UIImageView in .xib or storyboard file.
2. Link that name as you want. (Here i have taken imageView_AuthorPhoto)
Now code the below for make that in circular

imageView_AuthorPhoto.layer.masksToBounds = YES;

imageView_AuthorPhoto.layer.cornerRadius = imageView_AuthorPhoto.bounds.size.width/2;

imageView_AuthorPhoto.layer.borderWidth = 1.0;

imageView_AuthorPhoto.layer.borderColor =[UIColor colorWithRed:13/255 green:70/255 blue:131/255 alpha:1.0].CGColor;

And Set Image Accordingly

[imageView_AuthorPhoto  setImageWithURL:[NSURL   URLWithString:@"imageurl"] placeholderImage: useCache:<#(BOOL)#>];

Crop Image from an Image in Objective C

Here is the code to cut a piece from an Image or say UIImage

+ (UIImage *)cropImage:(UIImage *)image withArea:(CGRect)rect andScale:(int) scale{

    rect = CGRectMake(rect.origin.x*scale,

                      rect.origin.y*scale,

                      rect.size.width*scale,

                      rect.size.height*scale);

    

    CGImageRef imageRef = CGImageCreateWithImageInRect([image CGImage], rect);

    UIImage *img = [UIImage imageWithCGImage:imageRef

                                       scale:scale

                                 orientation:image.imageOrientation];

    CGImageRelease(imageRef);

    return img;

}

Masking Image with a transparent PNG

Hi i have made a function in which you can pass 2 UIImages and it will mask with the transparent Image
like

- (UIImageView*) maskImage:(UIImage *)image withMask:(UIImage *)maskImage {

    UIImageView *imageView = [[UIImageView alloc] initWithImage:image];

    CALayer *mask1 = [CALayer layer];

    mask1.contents = (id)[maskImage CGImage];

    mask1.frame = CGRectMake(0, 0, 1024, 768);

    imageView.layer.mask = mask1;

    imageView.layer.masksToBounds = YES;

    return imageView;

}

Its returns the UIImageView, which you can add directly in UIView. You can call this method like following:

    UIImage *image = [UIImage imageNamed:@"screenFull.png"];

    UIImage *mask = [UIImage imageNamed:@"screen_mask.png"];

    [self.completeSingleView addSubview:[self maskImage:image withMask:mask]];

Here completeSingleView is a UIView.


Reference is taken from 
http://stackoverflow.com/questions/5757386/how-to-mask-an-uiimageview

Drag and Drop UIImageView(s) inside UIView

i have put a UIView inside the xib and made the IBOutlet for this as property name - sampleView.

This UIView's x and y position is as per my project. So no need to worry about the parent view x and y position. Because we can make it relative to superview controller as follow:

//imagesView is Mutable Array and contains all UIImages.

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {

UITouch *touch = [[event allTouches] anyObject];

    

    for(int i=0;i<imagesInView.count;i++)

    {

        UIImageView *imgView = [imagesInView objectAtIndex:i];

        if (CGRectContainsPoint([imgView frame], [touch locationInView:self.secondFullImageView])) {

            //if ([touch tapCount] == 2)

                //[imgView setupNextDisplayString];

            CGPoint touchPoint = [touch locationInView:self.sampleView];//Here you need to concentrate for your UIImageView Parent

            [UIView beginAnimations:nil context:NULL];

            [UIView setAnimationDuration:0.3];

            imgView.center = touchPoint;

            CGAffineTransform transform = CGAffineTransformMakeScale(1.2, 1.2);

            imgView.transform = transform;

            [UIView commitAnimations];

            return;

        }

   }

}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {

    UITouch *touch = [[event allTouches] anyObject];

    for(int i=0;i<imagesInView.count;i++)

    {

        UIImageView *imgView = [imagesInView objectAtIndex:i];

        if (CGRectContainsPoint([imgView frame], [touch locationInView:self.sampleView])) {

            CGPoint location = [touch locationInView:self.sampleView];

            imgView.center = location;

        }

}

}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {

    UITouch *touch = [[event allTouches] anyObject];

    

    for(int i=0;i<imagesInView.count;i++)

    {

        UIImageView *imgView = [imagesInView objectAtIndex:i];

        if (CGRectContainsPoint([imgView frame], [touch locationInView:self.sampleView])) {

            //if ([touch tapCount] == 2)

            //[imgView setupNextDisplayString];

            [UIView beginAnimations:nil context:NULL];

            [UIView setAnimationDuration:0.3];

            CGAffineTransform transform = CGAffineTransformMakeScale(1, 1);

            imgView.transform = transform;

            [UIView commitAnimations];

            return;

        }

    }

}

This Code is not for Zoom, Pan or Rotate. For these features you can go here

http://varunxcode.blogspot.in/2013/01/simple-drag-drop-with-zoom-and-rotate.html