Calculate content size for UITextView

UITextView+LayoutHelpers.h

//
//  UITextView+LayoutHelpers.h
//
//  Created by Benjamin Bojko on 10/24/14.
//  Copyright (c) 2014 Benjamin Bojko. All rights reserved.
//

#import <UIKit/UIKit.h>

@interface UITextView (LayoutHelpers)

/**
 *  Returns the calculated size of its text contents by adding extra padding for content- and text-container-insets as well as text-container line-fragment-padding.
 */
- (CGSize)calculatedContentSize;

@end

UITextView+LayoutHelpers.m

//
//  UITextView+LayoutHelpers.m
//
//  Created by Benjamin Bojko on 10/24/14.
//  Copyright (c) 2014 Benjamin Bojko. All rights reserved.
//

#import "UITextView+LayoutHelpers.h"

@implementation UITextView (LayoutHelpers)

- (CGSize)calculatedContentSize {
	CGSize contentSize = self.bounds.size;
	UIEdgeInsets contentInsets = self.contentInset;
	UIEdgeInsets contentainerInsets = self.textContainerInset;
	
	float maxWidth = contentSize.width;
	maxWidth -= 2.0f * self.textContainer.lineFragmentPadding;
	maxWidth -= contentInsets.left + contentInsets.right + contentainerInsets.left + contentainerInsets.right;
	
	// Fix for font not being defined if the text view is not selectable in iOS 7
	BOOL selectable = self.selectable;
	self.selectable = YES;
	
	CGSize textSize = [self.attributedText boundingRectWithSize:CGSizeMake(maxWidth, CGFLOAT_MAX) options:NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading context:nil].size;
	
	self.selectable = selectable;
	
	contentSize.height = ceilf(textSize.height);
	contentSize.height += contentInsets.top + contentInsets.bottom + contentainerInsets.top + contentainerInsets.bottom;
	
	return contentSize;
}

@end