A UIImageView subclass which allows for external memers to set the intrinsicContentSize

NTVImageView.h

//
//  NTVImageView.h
//
//  Created by kiran on 27/10/2015.
//

#import <UIKit/UIKit.h>

@interface NTVImageView : UIImageView

/**
 *  A property to constrain the contentSize of the receiver.
 *
 *  This will automatically call `invalidateIntrinsicContentSize` on the receiver
 *  to trigger a layout pass.
 */
@property (assign, nonatomic, readwrite) CGSize constrainedSize;

@end

NTVImageView.m

//
//  NTVImageView.m
//
//  Created by kiran on 27/10/2015.
//

#import "NTVImageView.h"

@implementation NTVImageView

- (CGSize)intrinsicContentSize {
    return self.constrainedSize;
}

- (void)setConstrainedSize:(CGSize)constrainedSize {
    _constrainedSize = constrainedSize;
    [self invalidateIntrinsicContentSize];
}

@end