I have recently begun work on an app using Swift in Xcode and am trying to create a text bubble. To do this, I need to get the width of the longest row of text in a multi-row UILabel. For example, if I have this text (I automatically set line breaks after a certain length):
Hello there, this is
an example piece of text
I would like to return the width of the text in the second row. I have already tried using sizeToFit() which would drastically simplify my work, but because of my other code, this is not an option as it causes other problems (my code is below). Is there a purely programmatic way to get this value without using sizeToFit()? Any help would be much appreciated. My code:
bubbleContents.text = textMessage
bubbleContents.numberOfLines = 0
bubbleContents.lineBreakMode = .byWordWrapping
bubbleContents.bounds.size.width = 2000
var widthText = bubbleContents.intrinsicContentSize.width
bubbleContents.bounds.size.width = 266
print(textMessage)
print(widthText)
if widthText > 266 {
let numRows = Int(widthText/266)
print(numRows)
//bubbleContents.frame.origin.y += CGFloat((Double(numRows)*10.25))
var currentHeight = 44.0
currentHeight += Double((Double(numRows)*20.5))
bubbleContents.bounds.size.height = CGFloat(currentHeight)
heightOfCell = Double(currentHeight)
let originalTransform = self.bubbleContents.transform
let scaledTransform = originalTransform
let scaledAndTranslatedTransform = scaledTransform.translatedBy(x: 0, y: CGFloat(Double(numRows)*20.5))
//self.bubbleContents.transform = scaledAndTranslatedTransform
}
else {
heightOfCell = 44.0
}
bubble.frame = CGRect(x: 0, y: 0, width: Double(widthText + 30), height: heightOfCell - 4)
bubbleContents.center.y = bubble.center.y
Here is an image of what my current text bubbles look like:
You can use NSAttributedString,boundingRect(with:options:context:) method, begin by creating NSAttributedString with attributes such as font of your UILabel
let attributes: [NSAttributedString.Key : Any] = [.font: bubbleContents.font]
let atStr = NSAttributedString(string: textMessage, attributes: attributes)
Now use atStr.boundingRect(with:options:context:) method, like so:
let bounds = CGSize(width: 266.0, height: .greatestFiniteMagnitude)
let bubbleSize = atStr.boundingRect(with: bounds, options: [.usesLineFragmentOrigin, .usesFontLeading, .usesDeviceMetrics], context: nil).size
Usage:
bubble.frame.size.width = bubbleSize.width
bubble.frame.size.height = max(bubbleSize.height, 44.0)
Related
I am trying to add custom view (Label) as title view of navigation item.
but it is not appearing in centre
func setupNavigationMultilineTitle(title:String) {
let autoscrollLabel = EFAutoScrollLabel()
autoscrollLabel.text = title
autoscrollLabel.textAlignment = .center
autoscrollLabel.backgroundColor = .red
autoscrollLabel.font = AppTheme.Fonts.font(type: .Medium, size: 15)
autoscrollLabel.textColor = AppTheme.Colors.ColorsOfApp.header_color.color
autoscrollLabel.frame = CGRect(x: 0, y: 0, width:((self.navigationController?.navigationBar.frame.size.width ?? 0) - (self.navigationItem.leftBarButtonItem?.customView?.frame.width ?? 0) * 2) , height: 40)
self.navigationItem.titleView = autoscrollLabel
}
I have tried to use deduct width of custom view to show it in center but unfortunately it is not working.
I have also tried to get self.navigationItem.leftBarButtonItem.width but it returns 0. I confirmed that there is leftBarbutton item with po self.navigationItem.leftBarButtonItem
EDIT
This solves issue
autoscrollLabel.frame = CGRect(x: self.view.center.x - 125, y: 0, width: 250 , height: 40)
But I need dynamic solution
Any help would be appreciated
I debugged your scenario, hope it helps you and other developers,
When we assign tittleView width by calculating the space left after subtracting space of items, margins, padding etc then iOS calculate titleView X from the right side i.e. titleview.x = rightItem.x - width and we are expecting it like titleview.x = navbar.width/2 - width/2.
Please look below sample test cases.
Calculate width
let maxItemOnEitherSide = max(arrLeftItems.count, arrRightItems.count)
let widthOfItem : CGFloat = 30.0
let pading : CGFloat = 40
let aWidth : CGFloat = (self.navigationController?.navigationBar.frame.width)! - CGFloat(maxItemOnEitherSide) * widthOfItem * 2.0 - pading
let lblNavTitle = UILabel(frame: CGRect(x: 0, y: 0,
width: aWidth,
height: 40))
Case 1 : arrLeftItems.count = 1 and arrRightItems.count = 0.
Output :
Case 2 : arrLeftItems.count = 0 and arrRightItems.count = 1.
Hope above cases clear you out what we are expecting and what we are getting and the calculation that I wrote in first para i.e. titleview.x = rightItem.x - width.
Conclusion :
If rightBarItems have more items than leftBarItems then titleview will be in center, so you wont need to do anything but if leftBarItems have more items than rightBarItems then add blank items in right side to make it balance. It is weird for developers but seems like its the only solution.
Check the final output.
View Heirarchy
Output
If your navigation Item is part of a UINavigationController you could try
self.navigationController?.navigationBar.topItem?.leftBarButtonItem?.width ?? 0.0
Add my version code based on #dahiya_boy answers.
In my case, I have a custom button that has a more 30-width size. So, rather than multiply it by 30, I find a max from left and right items to find the max.
Below is the code:
func setCenterTitle(_ title: String) {
let navWidth = (navigationController?.navigationBar.frame.width).orZero
let leftItemsWidth = leftBarButtonItems.orEmptyArray.reduce(0) {
$0 + ($1.customView?.frame.width).orZero
}
let rightItemsWidth = rightBarButtonItems.orEmptyArray.reduce(0) {
$0 + ($1.customView?.frame.width).orZero
}
let maxItemsWidth = max(leftItemsWidth, rightItemsWidth)
let padding: CGFloat = 40
let labelWidth = navWidth - (maxItemsWidth * 2) - padding
let titleLabel = UILabel(frame: CGRect(x: 0, y: 0, width: labelWidth, height: 40))
titleLabel.text = title
titleLabel.textAlignment = .center
titleLabel.font = UIFont.boldSystemFont(ofSize: 16)
self.titleView = titleLabel
}
I have a dynamically changing text in TextView.I could not be able to get the content Height of TextView.
Here is what i tried.
let height = self.tvComment.contentSize.height
print("height",height)
let contentSizeComment = self.tvComment.sizeThatFits(self.tvComment.bounds.size)
print("height",contentSizeComment)
Why it's not getting the content height of TextView?
Hope you understand my problem.
Thanks in Advance
Usethis method to get the height -
func heightForString(text:String, font:UIFont, width:CGFloat) -> CGFloat{
let label:UILabel = UILabel(frame: CGRect(x: 0, y: 0, width: width, height: CGFloat.greatestFiniteMagnitude))
label.numberOfLines = 0
label.lineBreakMode = NSLineBreakMode.byWordWrapping
label.font = font
label.text = text
label.sizeToFit()
return label.frame.size.height
}
in textdidchange you can use this code,in order to resize when textchange
//approxi should be the width of your textview
let approxi = view.frame.width - 90
//size is the max width and height of textview,1000 can be what ever you want
let size = CGSize(width: approxi, height: 1000)
//dont forget to put your font and size
//chey is the text of thetext view
let attributes = [NSAttributedStringKey.font: UIFont.systemFont(ofSize: 15)]
let estim = NSString(string: chey).boundingRect(with: size, options: .usesLineFragmentOrigin, attributes: attributes, context: nil)
//estim is height
above it the first method,second method will come in edit
second method is
func pva() {
//what was the name of my textfield
let fixedwidth = what.frame.size.width - 40
let newsize = what.contentSize.height
self.hrightext.constant = newsize
self.view.layoutIfNeeded()
}
note: both are tested and works in swift4
Your just write code in below delegate of UITextView:-
func textViewDidChange(_ textView: UITextView!) {
let height = self.tvComment.contentSize.height
print("height",height)
let contentSizeComment = self.tvComment.sizeThatFits(self.tvComment.bounds.size)
print("height",contentSizeComment)
}
I hope it help you,
Thank you.
I'd like to create a method to calculate the optimal width of a multi-line label to attach several labels in a horizontal row of a fixed height.
With one line of text there is no problem:
let textAttributes: [String : Any] = [NSFontAttributeName: UIFont.preferredFont(forTextStyle: UIFontTextStyle.title2)]
let maximalWidth: CGFloat = text!.boundingRect(
with: CGSize(width: CGFloat.greatestFiniteMagnitude, height: height),
options: [NSStringDrawingOptions.usesLineFragmentOrigin],
attributes: textAttributes,
context: nil).size.width
As far as I understood, there is no option to indicate here, that I have several lines. This method works well in other direction when we calculate the height of the text with the fixed width. But I have the opposite goal.
As a variant, I can create a label based on the longest word (to be more precise, based on the widest word, as we can have several words with the same characters count, but different rendered width):
var sizeToReturn = CGSize()
let maxWordsCharacterCount = text?.maxWord.characters.count
let allLongWords: [String] = text!.wordList.filter {$0.characters.count == maxWordsCharacterCount}
var sizes: [CGFloat] = []
allLongWords.forEach {sizes.append($0.size(attributes: attributes).width)}
let minimalWidth = (sizes.max()! + constantElementsWidth)
I used here two String extensions to create words list and find all longest:
extension String {
var wordList: [String] {
return Array(Set(components(separatedBy: .punctuationCharacters).joined(separator: "").components(separatedBy: " "))).filter {$0.characters.count > 0}
}
}
extension String {
var maxWord: String {
if let max = self.wordList.max(by: {$1.characters.count > $0.characters.count}) {
return max
} else {return ""}
}
}
Not a bad option, but it looks ugly if we have the text that can't be fitted in three lines and that has several short words and one long word at the end. This long word, determined the width, will be just truncated. And more of that it looks not too good with 3 short words like:
Sell
the
car
Well, I have the minimum width, I have the maximum width. Perhaps, I can
go from maximum to minimum and catch when the label starts being truncated.
So I feel that there can be an elegant solution, but I'm stuck.
Hooray, I've found one of the possible solutions. You can use the code below in the playground:
import UIKit
import PlaygroundSupport
//: Just a view to launch playground timeline preview
let hostView = UIView(frame: CGRect(x: 0, y: 0, width: 320, height: 480))
hostView.backgroundColor = .lightGray
PlaygroundPage.current.liveView = hostView
// MARK: - Extensions
extension String {
var wordList: [String] {
return Array(Set(components(separatedBy: .punctuationCharacters).joined(separator: "").components(separatedBy: " "))).filter {$0.characters.count > 0}
}
}
extension String {
var longestWord: String {
if let max = self.wordList.max(by: {$1.characters.count > $0.characters.count}) {
return max
} else {return ""}
}
}
// MARK: - Mathod
func createLabelWithOptimalLabelWidth (
requestedHeight: CGFloat,
constantElementsWidth: CGFloat,
acceptableWidthForTextOfOneLine: CGFloat, //When we don't want the text to be shrinked
text: String,
attributes: [String:Any]
) -> UILabel {
let label = UILabel(frame: .zero)
label.attributedText = NSAttributedString(string: text, attributes: attributes)
let maximalLabelWidth = label.intrinsicContentSize.width
if maximalLabelWidth < acceptableWidthForTextOfOneLine {
label.frame = CGRect(origin: CGPoint.zero, size: CGSize(width: maximalLabelWidth, height: requestedHeight))
return label // We can go with this width
}
// Minimal width, calculated based on the longest word
let maxWordsCharacterCount = label.text!.longestWord.characters.count
let allLongWords: [String] = label.text!.wordList.filter {$0.characters.count == maxWordsCharacterCount}
var sizes: [CGFloat] = []
allLongWords.forEach {sizes.append($0.size(attributes: attributes).width)}
let minimalWidth = (sizes.max()! + constantElementsWidth)
// Height calculation
var flexibleWidth = maximalLabelWidth
var flexibleHeight = CGFloat()
var optimalWidth = CGFloat()
var optimalHeight = CGFloat()
while (flexibleHeight <= requestedHeight && flexibleWidth >= minimalWidth) {
optimalWidth = flexibleWidth
optimalHeight = flexibleHeight
flexibleWidth -= 1
flexibleHeight = label.attributedText!.boundingRect(
with: CGSize(width: flexibleWidth, height: CGFloat.greatestFiniteMagnitude),
options: [NSStringDrawingOptions.usesLineFragmentOrigin],
context: nil).size.height
print("Width: \(flexibleWidth)")
print("Height: \(flexibleHeight)")
print("_______________________")
}
print("Final Width: \(optimalWidth)")
print("Final Height: \(optimalHeight)")
label.frame = CGRect(origin: CGPoint.zero, size: CGSize(width: optimalWidth+constantElementsWidth, height: requestedHeight))
return label
}
// MARK: - Inputs
let text: String? = "Determine the fair price"//nil//"Select the appropriate payment method"//"Finalize the order" //"Sell the car"//"Check the payment method"
let font = UIFont.preferredFont(forTextStyle: UIFontTextStyle.callout)
let paragraphStyle = NSMutableParagraphStyle()
paragraphStyle.lineBreakMode = .byWordWrapping
paragraphStyle.allowsDefaultTighteningForTruncation = true
let attributes: [String:Any] = [
NSFontAttributeName: font,
NSParagraphStyleAttributeName: paragraphStyle,
NSBaselineOffsetAttributeName: 0
]
if text != nil {
let label = createLabelWithOptimalLabelWidth(requestedHeight: 70, constantElementsWidth: 0, acceptableWidthForTextOfOneLine: 120, text: text!, attributes: attributes)
label.frame.width
label.frame.height
label.backgroundColor = .white
label.lineBreakMode = .byWordWrapping
label.numberOfLines = 3
hostView.addSubview(label)
}
In my app I have a UILabel with two lines preset. I can set the text alignment to either .left or .justified.
If I set it to .left, there is no layout issue if there is enough space between the last word in a line and the maximum x position of the label. Yet, when there is not so much space, so that the last word is very near the maximum x position, it looks kinda weird, because it is not exactly right-aligned (as it would be with .justified.
If I set it to .justified, it is always aligned well, yet sometimes the distance between the individual characters looks weird.
What I'm looking for is a way to dynamically adjust the text alignment depending on the distance between the last word in the first line to the maximum x position of the label. Say, if the position of the last character of the last word is smaller than 50, I want to have text alignment .left, otherwise I'd like to have .justified. Is there any way on how to accomplish this?
I took a quite hacky approach which takes some processing power, but it seems to work.
First of all, I fetch the string in the first line of the label using this extension:
import CoreText
extension UILabel {
/// Returns the String displayed in the first line of the UILabel or "" if text or font is missing
var firstLineString: String {
guard let text = self.text else { return "" }
guard let font = self.font else { return "" }
let rect = self.frame
let attStr = NSMutableAttributedString(string: text)
attStr.addAttribute(String(kCTFontAttributeName), value: CTFontCreateWithName(font.fontName as CFString, font.pointSize, nil), range: NSMakeRange(0, attStr.length))
let frameSetter = CTFramesetterCreateWithAttributedString(attStr as CFAttributedString)
let path = CGMutablePath()
path.addRect(CGRect(x: 0, y: 0, width: rect.size.width + 7, height: 100))
let frame = CTFramesetterCreateFrame(frameSetter, CFRangeMake(0, 0), path, nil)
guard let line = (CTFrameGetLines(frame) as! [CTLine]).first else { return "" }
let lineString = text[text.startIndex...text.index(text.startIndex, offsetBy: CTLineGetStringRange(line).length-2)]
return lineString
}
}
After that I calculate the width, a label with line number 1 and fixed height would require for that string using this extension:
extension UILabel {
/// Get required width for a UILabel depending on its text content and font configuration
class func calculateWidth(text: String, height: CGFloat, font: UIFont) -> CGFloat {
let label = UILabel(frame: CGRect(x: 0, y: 0, width: CGFloat.greatestFiniteMagnitude, height: height))
label.numberOfLines = 1
label.font = font
label.text = text
label.sizeToFit()
return label.frame.size.width
}
}
Based on that, I can calculate the distance to the right and decide whether to choose text alignment .left or .justified, so the main code looks like this:
// Set text
myLabel.text = someString
// Change text alignment depending on distance to right
let firstLineString = myLabel.firstLineString
let distanceToRight = myLabel.frame.size.width - UILabel.calculateWidth(text: firstLineString, height: myLabel.frame.size.height, font: myLabel.font)
myLabel.textAlignment = distanceToRight < 20 ? .justified : .left
How can I find the actual number of lines of a UILabel after I have initialized it with a text and a font? I have set its numberOfLines property to 0, so it will expand to however many lines are necessary. But then, how can I find out how many lines it finally got after I set its text?
I found similar questions, but none seems to provide a concise answer and it seems to me that it must be really easy to get it without any overhead on juggling around with the boundingRectWithSize or sizeWithFont,...
None of these worked for me. Below one did,
Swift 4.2:
extension UILabel {
func calculateMaxLines() -> Int {
let maxSize = CGSize(width: frame.size.width, height: CGFloat(Float.infinity))
let charSize = font.lineHeight
let text = (self.text ?? "") as NSString
let textSize = text.boundingRect(with: maxSize, options: .usesLineFragmentOrigin, attributes: [NSAttributedString.Key.font: font], context: nil)
let linesRoundedUp = Int(ceil(textSize.height/charSize))
return linesRoundedUp
}
}
Swift 4/4.1:
extension UILabel {
func calculateMaxLines() -> Int {
let maxSize = CGSize(width: frame.size.width, height: CGFloat(Float.infinity))
let charSize = font.lineHeight
let text = (self.text ?? "") as NSString
let textSize = text.boundingRect(with: maxSize, options: .usesLineFragmentOrigin, attributes: [.font: font], context: nil)
let linesRoundedUp = Int(ceil(textSize.height/charSize))
return linesRoundedUp
}
}
Swift 3:
extension UILabel {
func calculateMaxLines() -> Int {
let maxSize = CGSize(width: frame.size.width, height: CGFloat(Float.infinity))
let charSize = font.lineHeight
let text = (self.text ?? "") as NSString
let textSize = text.boundingRect(with: maxSize, options: .usesLineFragmentOrigin, attributes: [NSFontAttributeName: font], context: nil)
let linesRoundedUp = Int(ceil(textSize.height/charSize))
return linesRoundedUp
}
}
Swift 5 (IOS 12.2)
Get max number of lines required for a label to render the text without truncation.
extension UILabel {
var maxNumberOfLines: Int {
let maxSize = CGSize(width: frame.size.width, height: CGFloat(MAXFLOAT))
let text = (self.text ?? "") as NSString
let textHeight = text.boundingRect(with: maxSize, options: .usesLineFragmentOrigin, attributes: [.font: font], context: nil).height
let lineHeight = font.lineHeight
return Int(ceil(textHeight / lineHeight))
}
}
Get max number of lines can be displayed in a label with constrained bounds. Use this property after assigning text to label.
extension UILabel {
var numberOfVisibleLines: Int {
let maxSize = CGSize(width: frame.size.width, height: CGFloat(MAXFLOAT))
let textHeight = sizeThatFits(maxSize).height
let lineHeight = font.lineHeight
return Int(ceil(textHeight / lineHeight))
}
}
Usage
print(yourLabel.maxNumberOfLines)
print(yourLabel.numberOfVisibleLines)
Firstly set text in UILabel
First Option :
Firstly calculate height for text according to font :
NSInteger lineCount = 0;
CGSize labelSize = (CGSize){yourLabel.frame.size.width, MAXFLOAT};
CGRect requiredSize = [self boundingRectWithSize:labelSize options:NSStringDrawingUsesLineFragmentOrigin attributes:#{NSFontAttributeName: yourLabel.font} context:nil];
Now calculate number of lines :
int charSize = lroundf(yourLabel.font.lineHeight);
int rHeight = lroundf(requiredSize.height);
lineCount = rHeight/charSize;
NSLog(#"No of lines: %i",lineCount);
Second Option :
NSInteger lineCount = 0;
CGSize textSize = CGSizeMake(yourLabel.frame.size.width, MAXFLOAT);
int rHeight = lroundf([yourLabel sizeThatFits:textSize].height);
int charSize = lroundf(yourLabel.font.lineHeight);
lineCount = rHeight/charSize;
NSLog(#"No of lines: %i",lineCount);
Here is a swift version of #Paresh solution:
func lines(label: UILabel) -> Int {
let textSize = CGSize(width: label.frame.size.width, height: CGFloat(Float.infinity))
let rHeight = lroundf(Float(label.sizeThatFits(textSize).height))
let charSize = lroundf(Float(label.font.lineHeight))
let lineCount = rHeight/charSize
return lineCount
}
EDIT: I don't know why, but the code is returning 2 more lines than the actual number of lines, for my solution, I just subtracted them before returning lineCount.
Swift 5.2
The main point to make it work for me was to call label.layoutIfNeeded() because I was using autoLayout, otherwise it doesnt work.
func actualNumberOfLines(label: UILabel) -> Int {
// You have to call layoutIfNeeded() if you are using autoLayout
label.layoutIfNeeded()
let myText = label.text! as NSString
let rect = CGSize(width: label.bounds.width, height: CGFloat.greatestFiniteMagnitude)
let labelSize = myText.boundingRect(with: rect, options: .usesLineFragmentOrigin, attributes: [NSAttributedString.Key.font: label.font as Any], context: nil)
return Int(ceil(CGFloat(labelSize.height) / label.font.lineHeight))
}
Credits to: https://gist.github.com/fuxingloh/ccf26bb68f4b8e6cfd02, which provided the solution in an older swift version, and for mentioning the importance of layoutIfNeeded().
The other answers here don't respect the numberOfLines property of UILabel when it is set to something other than 0.
Here's another option you can add to your category or subclass:
- (NSUInteger)lineCount
{
CGSize size = [self sizeThatFits:CGSizeMake(self.frame.size.width, CGFLOAT_MAX)];
return MAX((int)(size.height / self.font.lineHeight), 0);
}
Some notes:
I'm using this on a UILabel with attributed text, without ever actually setting the font property, and it's working fine. Obviously you would run into issues if you were using multiple fonts in your attributedText.
If you are subclassing UILabel to have custom edge insets (for example by overriding drawTextInRect:, which is a neat trick I found here), then you must remember to take those insets into account when calculating the size above. For example: CGSizeMake(self.frame.size.width - (self.insets.left + self.insets.right), CGFLOAT_MAX)
Here is the Swift3 Code
here you can define Int value and get the height of text size by using (MAXFLOAT) and using that height you can get the total height of UILabel and by deviding that total height by character size you can get the actual line count of UILabel.
var lineCount: Int = 0
var textSize = CGSize(width: CGFloat(yourLabel.frame.size.width), height: CGFloat(MAXFLOAT))
var rHeight: Int = lroundf(yourLabel.sizeThatFits(textSize).height)
var charSize: Int = lroundf(yourLabel.font.leading)
lineCount = rHeight / charSize
print("No of lines: \(lineCount)")
It seems that the official developer website mentions one solution Counting Lines of Text in Objc. However, it assumes you have a reference to a text view configured with a layout manager, text storage, and text container. Unfortunately, UILabel doesn't expose those to us, so we need create them with the same configuration as the UILabel.
I translated the Objc code to swift as following. It seems work well for me.
extension UILabel {
var actualNumberOfLines: Int {
let textStorage = NSTextStorage(attributedString: self.attributedText!)
let layoutManager = NSLayoutManager()
textStorage.addLayoutManager(layoutManager)
let textContainer = NSTextContainer(size: self.bounds.size)
textContainer.lineFragmentPadding = 0
textContainer.lineBreakMode = self.lineBreakMode
layoutManager.addTextContainer(textContainer)
let numberOfGlyphs = layoutManager.numberOfGlyphs
var numberOfLines = 0, index = 0, lineRange = NSMakeRange(0, 1)
while index < numberOfGlyphs {
layoutManager.lineFragmentRect(forGlyphAt: index, effectiveRange: &lineRange)
index = NSMaxRange(lineRange)
numberOfLines += 1
}
return numberOfLines
}
}
You can find the total number of line available in your custom label
Please check this code...
NSInteger numberOfLines = [self lineCountForText:#"YOUR TEXT"];
- (int)lineCountForText:(NSString *) text
{
UIFont *font = [UIFont systemFontOfSize: 15.0];
int width=Your_LabelWidht;
CGRect rect = [text boundingRectWithSize:CGSizeMake(width, MAXFLOAT) options:NSStringDrawingUsesLineFragmentOrigin attributes:#{NSFontAttributeName : font} context:nil];
return ceil(rect.size.height / font.lineHeight);
}
Following up on #Prince's answer, I now implemented a category on UILabel as follows (note that I corrected some minor syntax mistakes in his answer that wouldn't let the code compile):
UILabel+Util.h
#import <UIKit/UIKit.h>
#interface UILabel (Util)
- (NSInteger)lineCount;
#end
UILabel+Util.,
#import "UILabel+Util.h"
#implementation UILabel (Util)
- (NSInteger)lineCount
{
// Calculate height text according to font
NSInteger lineCount = 0;
CGSize labelSize = (CGSize){self.frame.size.width, FLT_MAX};
CGRect requiredSize = [self.text boundingRectWithSize:labelSize options:NSStringDrawingUsesLineFragmentOrigin attributes:#{NSFontAttributeName: self.font} context:nil];
// Calculate number of lines
int charSize = self.font.leading;
int rHeight = requiredSize.size.height;
lineCount = rHeight/charSize;
return lineCount;
}
#end
Xamarin iOS
label.Text = text;
var lineCount = 0;
var textSize = new CGSize(label.Frame.Size.Width, float.MaxValue);
var height = label.SizeThatFits(textSize).Height;
var fontHeight = label.Font.LineHeight;
lineCount = Convert.ToInt32(height / fontHeight);
Note that #kurt-j's answer will not always work. In some cases, you will have to manually provide the width of label. Since these cases exist, it is a good idea to have an optional width parameter, even if you don't end up using it.
Swift 4.2:
extension UILabel {
func calculateMaxLines(actualWidth: CGFloat?) -> Int {
var width = frame.size.width
if let actualWidth = actualWidth {
width = actualWidth
}
let maxSize = CGSize(width: width, height: CGFloat(Float.infinity))
let charSize = font.lineHeight
let text = (self.text ?? "") as NSString
let textSize = text.boundingRect(with: maxSize, options: .usesLineFragmentOrigin, attributes: [NSAttributedString.Key.font: font], context: nil)
let linesRoundedUp = Int(ceil(textSize.height/charSize))
return linesRoundedUp
}
}
let l = UILabel()
l.numberOfLines = 0
l.layer.frame.size.width = self.view.frame.width - 40 /*padding(20 + 20)*/
l.font = UIFont(name: "BwModelica-Bold", size: 16.0)
l.text = "Random Any length Text!!"
let noOfLines = ceil(l.intrinsicContentSize.width / l.frame.size.width)
let lbl_height = noOfLines * l.intrinsicContentSize.height
This will be your Exact dynamic height of Label and Number of lines. Happy coding!!!
Xamarin.iOS
Thanks to the answers everyone provided above.
This gets number of visible lines.
public static int VisibleLineCount(this UILabel label)
{
var textSize = new CGSize(label.Frame.Size.Width, nfloat.MaxValue);
nfloat rHeight = label.SizeThatFits(textSize).Height;
nfloat charSize = label.Font.LineHeight;
return Convert.ToInt32(rHeight / charSize);
}
This gets actual number of lines the text will occupy on screen.
public static int LineCount(this UILabel label)
{
var maxSize = new CGSize(label.Frame.Size.Width, nfloat.MaxValue);
var charSize = label.Font.LineHeight;
var text = (label.Text ?? "").ToNSString();
var textSize = text.GetBoundingRect(maxSize, NSStringDrawingOptions.UsesLineFragmentOrigin, new UIStringAttributes() { Font = label.Font }, null);
return Convert.ToInt32(textSize.Height / charSize);
}
A helper method I find useful for my use case.
public static bool IsTextTruncated(this UILabel label)
{
if (label.Lines == 0)
{
return false;
}
return (label.LineCount() > label.Lines);
}
To get a more accurate line count:
Use font.lineHeight instead of font.pointSize
round() the line count after division
Swift 5.4
Refactor solution of Fernando Cardenas to UILabel extension
private extension UILabel {
var actualNumberOfLines: Int {
guard let text = self.text else {
return 0
}
layoutIfNeeded()
let rect = CGSize(width: bounds.width, height: CGFloat.greatestFiniteMagnitude)
let labelSize = text.boundingRect(
with: rect,
options: .usesLineFragmentOrigin,
attributes: [NSAttributedString.Key.font: font as Any],
context: nil)
return Int(ceil(CGFloat(labelSize.height) / font.lineHeight))
}
}
⚠️ Nor lineHeight, nor leading is sufficient on its own.
The font.lineHeight is the height of the glyphs, it spans from descender (the bottom of the lowest glyph) to ascender (the top of the highest glyph). Also, note that lineHeight can be override for an attributed string. The font.leading is the additional (may be negative, though) space between (!) the lines (see docs for yourself). If you use the system fonts, you get different leading values for almost every point size.
So e.g. the height of a label with 5 lines is consist of 5 lineHeight and 4 leading (yet the leading value is often small enough to make the above solutions work up until a point where you start to work with a multitude of lines.
So the correct (pseudo) formula should be:
(frame.size.height + font.leading) / (font.lineHeight + font.leading)
Also also, if the attributed string has an attachment that is too big (higher than the ascender of the font), then it also alters the line height for that row.