Fix Clipping UITextView

FontMeasure.swift

//: Playground - noun: a place where people can play

import XCPlayground
import UIKit

// MARK: - Paragraph Styles

let headlineParagraphStyle = NSMutableParagraphStyle()
headlineParagraphStyle.lineHeightMultiple = 0.8

// MARK: Attributes

let attributes = [
    NSFontAttributeName: UIFont(name: "BanglaSangamMN-Bold", size: 42)!,
    NSParagraphStyleAttributeName: headlineParagraphStyle
]

// MARK: String

let string = "Rivals pounce at 6 a.m. breakfast clubbin’"
let attributedString = NSAttributedString(string: string, attributes: attributes)

// MARK: - Views

let view = UIView(frame: UIScreen.mainScreen().bounds)
XCPShowView("view", view)

let textView = UITextView()
textView.frame = view.bounds
textView.editable = false
textView.selectable = false
textView.scrollEnabled = false
textView.textContainerInset = UIEdgeInsetsZero
textView.textContainer.lineFragmentPadding = 0
textView.attributedText = attributedString
textView.textColor = UIColor.whiteColor()
textView.backgroundColor = UIColor(red: 0.99, green: 0.32, blue: 0.20, alpha:1)
view.addSubview(textView)

// MARK: - Measure Bounds

let maxSize = CGSize(width: view.bounds.width, height: CGFloat.max)
let options:NSStringDrawingOptions = .UsesLineFragmentOrigin | .UsesFontLeading
let boundingRect = attributedString.boundingRectWithSize(maxSize, options: options, context: nil)
textView.frame = CGRect(origin: CGPoint.zeroPoint, size: boundingRect.size)

// MARK: Shift Top Down

let font = attributes[NSFontAttributeName] as! UIFont
let paragraph = attributes[NSParagraphStyleAttributeName] as! NSParagraphStyle

let shiftTop = ceil(font.lineHeight - paragraph.lineHeightMultiple * font.lineHeight)
textView.textContainerInset.top = shiftTop
textView.frame.size.height += shiftTop