On the storyboard I created a text view. Inserted two paragraphs of text content inside textview. Selected custom attributes on the storyboard and made some words bold. When I run the simulator, everything is ok. But when I set the font size programmatically with respect to the "view.frame.height", the bold words which I set on the storyboard resets to regular words.
Code: "abcTextView.font = abcTextView.font?.withSize(self.view.frame.height * 0.021)"
I couldn't get past this issue. How can I solve this?
The problem is that you're working with an AttributedString. Take a look at Manmal's excellent answer here if you want more context, and an explanation of how the code works:
NSAttributedString, change the font overall BUT keep all other attributes?
Here's an easy application of the extension he provides, to put it in the context of your problem:
class ViewController: UIViewController {
#IBOutlet weak var myTextView: UITextView!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
let newString = NSMutableAttributedString(attributedString: myTextView.attributedText)
newString.setFontFace(font: UIFont.systemFont(ofSize: self.view.frame.height * 0.033))
myTextView.attributedText = newString
}
}
extension NSMutableAttributedString {
func setFontFace(font: UIFont, color: UIColor? = nil) {
beginEditing()
self.enumerateAttribute(
.font,
in: NSRange(location: 0, length: self.length)
) { (value, range, stop) in
if let f = value as? UIFont,
let newFontDescriptor = f.fontDescriptor
.withFamily(font.familyName)
.withSymbolicTraits(f.fontDescriptor.symbolicTraits) {
let newFont = UIFont(
descriptor: newFontDescriptor,
size: font.pointSize
)
removeAttribute(.font, range: range)
addAttribute(.font, value: newFont, range: range)
if let color = color {
removeAttribute(
.foregroundColor,
range: range
)
addAttribute(
.foregroundColor,
value: color,
range: range
)
}
}
}
endEditing()
}
}
I'm using NSMutableAttributedString to format text strings. It works fine, even with the links. But for some reason the font size for the links won't change even though I have specified the size. My function looks like this: (There are comments in the code to explain everything)
func formatfunc2(chapter: String, boldStart: Int, boldLength: Int, italicsStart: Int, italicsLength: Int, link: [String], linkStart: [Int], linkEnd: [Int]) -> NSAttributedString {
let bold = UIFont.boldSystemFont(ofSize: 17)
let italics = UIFont.italicSystemFont(ofSize: 17)
//BELOW IS MY FORMAT FOR THE HYPERLINK
let hyperlink = UIFont.boldSystemFont(ofSize: 17)
let attributedString = NSMutableAttributedString.init(string: chapter, attributes: [NSAttributedStringKey.font: UIFont.systemFont(ofSize: 17)])
//BELOW ARE FORMAT FOR BOLD AND ITALICS - AND THEY WORK FINE
attributedString.addAttribute(.font, value: bold, range: NSRange.init(location: boldStart, length: boldLength))
attributedString.addAttribute(.font, value: italics, range: NSRange.init(location: italicsStart, length: italicsLength))
//THE LOOP GOES THROUGH ALL LINK ADRESSES AND THEIR POSITIONS
for i in 0...link.count - 1 {
//HERE I ADD THE FONT SIZE TO THE SAME POSITION AS THE LINKS, BUT IT DOESN'T WORK
attributedString.addAttribute(.font, value: hyperlink, range: NSRange.init(location: linkStart[i], length: linkEnd[i]))
let url = URL(string: link[i]) as! URL
//MY THEORY IS THAT THE CODE BELOW OVERRIDES THE PREVIOUS FONT SIZE
attributedString.setAttributes([.link: url], range: NSMakeRange(linkStart[i], linkEnd[i]))
}
return attributedString
}
So the format works fine for all other text but not for the links. Can I add font size in the last code part instead? :
attributedString.setAttributes([.link: url], range: NSMakeRange(linkStart[i], linkEnd[i]))
Say I have an NSMutableAttributedString .
The string has a varied mix of formatting throughout:
Here is an example:
This string is hell to change in iOS, it really sucks.
However, the font per se is not the font you want.
I want to:
for each and every character, change that character to a specific font (say, Avenir)
BUT,
for each and every character, keep the mix of other attributions (bold, italic, colors, etc etc) which was previously in place on that character.
How the hell do you do this?
Note:
if you trivially add an attribute "Avenir" over the whole range: it simply deletes all the other attribute ranges, you lose all formatting. Unfortunately, attributes are not, in fact "additive".
Since rmaddy's answer did not work for me (f.fontDescriptor.withFace(font.fontName) does not keep traits like bold), here is an updated Swift 4 version that also includes color updating:
extension NSMutableAttributedString {
func setFontFace(font: UIFont, color: UIColor? = nil) {
beginEditing()
self.enumerateAttribute(
.font,
in: NSRange(location: 0, length: self.length)
) { (value, range, stop) in
if let f = value as? UIFont,
let newFontDescriptor = f.fontDescriptor
.withFamily(font.familyName)
.withSymbolicTraits(f.fontDescriptor.symbolicTraits) {
let newFont = UIFont(
descriptor: newFontDescriptor,
size: font.pointSize
)
removeAttribute(.font, range: range)
addAttribute(.font, value: newFont, range: range)
if let color = color {
removeAttribute(
.foregroundColor,
range: range
)
addAttribute(
.foregroundColor,
value: color,
range: range
)
}
}
}
endEditing()
}
}
Or, if your mix-of-attributes does not include font,
then you don't need to remove old font:
let myFont: UIFont = .systemFont(ofSize: UIFont.systemFontSize);
myAttributedText.addAttributes(
[NSAttributedString.Key.font: myFont],
range: NSRange(location: 0, length: myAttributedText.string.count));
Notes
The problem with f.fontDescriptor.withFace(font.fontName) is that it removes symbolic traits like italic, bold or compressed, since it will for some reason override those with default traits of that font face. Why this is so totally eludes me, it might even be an oversight on Apple's part; or it's "not a bug, but a feature", because we get the new font's traits for free.
So what we have to do is create a font descriptor that has the symbolic traits from the original font's font descriptor: .withSymbolicTraits(f.fontDescriptor.symbolicTraits). Props to rmaddy for the initial code on which I iterated.
I've already shipped this in a production app where we parse a HTML string via NSAttributedString.DocumentType.html and then change the font and color via the extension above. No problems so far.
Here is a much simpler implementation that keeps all attributes in place, including all font attributes except it allows you to change the font face.
Note that this only makes use of the font face (name) of the passed in font. The size is kept from the existing font. If you want to also change all of the existing font sizes to the new size, change f.pointSize to font.pointSize.
extension NSMutableAttributedString {
func replaceFont(with font: UIFont) {
beginEditing()
self.enumerateAttribute(.font, in: NSRange(location: 0, length: self.length)) { (value, range, stop) in
if let f = value as? UIFont {
let ufd = f.fontDescriptor.withFamily(font.familyName).withSymbolicTraits(f.fontDescriptor.symbolicTraits)!
let newFont = UIFont(descriptor: ufd, size: f.pointSize)
removeAttribute(.font, range: range)
addAttribute(.font, value: newFont, range: range)
}
}
endEditing()
}
}
And to use it:
let someMutableAttributedString = ... // some attributed string with some font face you want to change
someMutableAttributedString.replaceFont(with: UIFont.systemFont(ofSize: 12))
my two cents for OSX/AppKit>
extension NSAttributedString {
// replacing font to all:
func setFont(_ font: NSFont, range: NSRange? = nil)-> NSAttributedString {
let mas = NSMutableAttributedString(attributedString: self)
let range = range ?? NSMakeRange(0, self.length)
mas.addAttributes([.font: font], range: range)
return NSAttributedString(attributedString: mas)
}
// keeping font, but change size:
func setFont(size: CGFloat, range: NSRange? = nil)-> NSAttributedString {
let mas = NSMutableAttributedString(attributedString: self)
let range = range ?? NSMakeRange(0, self.length)
mas.enumerateAttribute(.font, in: range) { value, range, stop in
if let font = value as? NSFont {
let name = font.fontName
let newFont = NSFont(name: name, size: size)
mas.addAttributes([.font: newFont!], range: range)
}
}
return NSAttributedString(attributedString: mas)
}
Important -
rmaddy has invented an entirely new technique for this annoying problem in iOS.
The answer by manmal is the final perfected version.
Purely for the historical record here is roughly how you'd go about doing it the old days...
// carefully convert to "our" font - "re-doing" any other formatting.
// change each section BY HAND. total PITA.
func fixFontsInAttributedStringForUseInApp() {
cachedAttributedString?.beginEditing()
let rangeAll = NSRange(location: 0, length: cachedAttributedString!.length)
var boldRanges: [NSRange] = []
var italicRanges: [NSRange] = []
var boldANDItalicRanges: [NSRange] = [] // WTF right ?!
cachedAttributedString?.enumerateAttribute(
NSFontAttributeName,
in: rangeAll,
options: .longestEffectiveRangeNotRequired)
{ value, range, stop in
if let font = value as? UIFont {
let bb: Bool = font.fontDescriptor.symbolicTraits.contains(.traitBold)
let ii: Bool = font.fontDescriptor.symbolicTraits.contains(.traitItalic)
// you have to carefully handle the "both" case.........
if bb && ii {
boldANDItalicRanges.append(range)
}
if bb && !ii {
boldRanges.append(range)
}
if ii && !bb {
italicRanges.append(range)
}
}
}
cachedAttributedString!.setAttributes([NSFontAttributeName: font_f], range: rangeAll)
for r in boldANDItalicRanges {
cachedAttributedString!.addAttribute(NSFontAttributeName, value: font_fBOTH, range: r)
}
for r in boldRanges {
cachedAttributedString!.addAttribute(NSFontAttributeName, value: font_fb, range: r)
}
for r in italicRanges {
cachedAttributedString!.addAttribute(NSFontAttributeName, value: font_fi, range: r)
}
cachedAttributedString?.endEditing()
}
.
Footnote. Just for clarity on a related point. This sort of thing inevitably starts as a HTML string. Here's a note on how to convert a string that is html to an NSattributedString .... you will end up with nice attribute ranges (italic, bold etc) BUT the fonts will be fonts you don't want.
fileprivate extension String {
func htmlAttributedString() -> NSAttributedString? {
guard let data = self.data(using: String.Encoding.utf16, allowLossyConversion: false) else { return nil }
guard let html = try? NSMutableAttributedString(
data: data,
options: [NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType],
documentAttributes: nil) else { return nil }
return html
}
}
.
Even that part of the job is non-trivial, it takes some time to process. In practice you have to background it to avoid flicker.
Obj-C version of #manmal's answer
#implementation NSMutableAttributedString (Additions)
- (void)setFontFaceWithFont:(UIFont *)font color:(UIColor *)color {
[self beginEditing];
[self enumerateAttribute:NSFontAttributeName
inRange:NSMakeRange(0, self.length)
options:0
usingBlock:^(id _Nullable value, NSRange range, BOOL * _Nonnull stop) {
UIFont *oldFont = (UIFont *)value;
UIFontDescriptor *newFontDescriptor = [[oldFont.fontDescriptor fontDescriptorWithFamily:font.familyName] fontDescriptorWithSymbolicTraits:oldFont.fontDescriptor.symbolicTraits];
UIFont *newFont = [UIFont fontWithDescriptor:newFontDescriptor size:font.pointSize];
if (newFont) {
[self removeAttribute:NSFontAttributeName range:range];
[self addAttribute:NSFontAttributeName value:newFont range:range];
}
if (color) {
[self removeAttribute:NSForegroundColorAttributeName range:range];
[self addAttribute:NSForegroundColorAttributeName value:newFont range:range];
}
}];
[self endEditing];
}
#end
There is a tiny bug in the accepted answer causing the original font size to get lost.
To fix this simply replace
font.pointSize
with
f.pointSize
This ensures that e.g. H1 and H2 headings have the correct size.
Swift 5
This properly scales the font size, as other answers overwrite the font size, which may differ, like with sub, sup attribute
For iOS replace NSFont->UIFont and NSColor->UIColor
extension NSMutableAttributedString {
func setFont(_ font: NSFont, textColor: NSColor? = nil) {
guard let fontFamilyName = font.familyName else {
return
}
beginEditing()
enumerateAttribute(NSAttributedString.Key.font, in: NSMakeRange(0, length), options: []) { (value, range, stop) in
if let oldFont = value as? NSFont {
let descriptor = oldFont
.fontDescriptor
.withFamily(fontFamilyName)
.withSymbolicTraits(oldFont.fontDescriptor.symbolicTraits)
// Default font is always Helvetica 12
// See: https://developer.apple.com/documentation/foundation/nsattributedstring?language=objc
let size = font.pointSize * (oldFont.pointSize / 12)
let newFont = NSFont(descriptor: descriptor, size: size) ?? oldFont
addAttribute(NSAttributedString.Key.font, value: newFont, range: range)
}
}
if let textColor = textColor {
addAttributes([NSAttributedString.Key.foregroundColor:textColor], range: NSRange(location: 0, length: length))
}
endEditing()
}
}
extension NSAttributedString {
func settingFont(_ font: NSFont, textColor: NSColor? = nil) -> NSAttributedString {
let ms = NSMutableAttributedString(attributedString: self)
ms.setFont(font, textColor: textColor)
return ms
}
}
Would it be valid to let a UITextField do the work?
Like this, given attributedString and newfont:
let textField = UITextField()
textField.attributedText = attributedString
textField.font = newFont
let resultAttributedString = textField.attributedText
Sorry, I was wrong, it keeps the "Character Attributes" like NSForegroundColorAttributeName, e.g. the colour, but not the UIFontDescriptorSymbolicTraits, which describe bold, italic, condensed, etc.
Those belong to the font and not the "Character Attributes". So if you change the font, you are changing the traits as well. Sorry, but my proposed solution does not work. The target font needs to have all traits available as the original font for this to work.
How to do to get the selected string from a NSTextView in Swift?
// create a range of selected text
let range = mainTextField.selectedRange()
// this works but I need a plain string not an attributed string
let str = mainTextField.textStorage?.attributedSubstring(from: range)
Maybe I have to add an intermediate step where I get the full string and then apply the range on it?
What about
let str = mainTextField.text.substring(with: range)
Edit:
This should work now:
let range = mainTextField.selectedRange() // Returns NSRange :-/ (instead of Range)
let str = mainTextField.string as NSString? // So we cast String? to NSString?
let substr = str?.substring(with: range) // To be able to use the range in substring(with:)
The code snippet in the Swift 5. That's not very hard but repeated
let string = textView.attributedString().string
let selectedRange = textView.selectedRange()
let startIndex = string.index(string.startIndex, offsetBy: selectedRange.lowerBound)
let endIndex = string.index(string.startIndex, offsetBy: selectedRange.upperBound)
let substring = textView.attributedString().string[startIndex..<endIndex]
let selectedString = String(substring)
In case anyone is having issues with the selectedRanges() not returning the proper range for an NSTextView, make sure that you have made your NSTextView selectable. I don't know if it's not selectable by default but I had to enable it;
textView.isSelectable = true
I was trying this in Swift 5 using #user25917 code sample above and I couldn't get the ranges no matter what. I was getting a visual confirmation the text was selected through highlighting which threw me off. This was driving me mad for a few hours.
This may be helpfull for you :
let textView = NSTextView(frame: NSMakeRect(0, 0, 100, 100))
let attributes = [NSForegroundColorAttributeName: NSColor.redColor(),
NSBackgroundColorAttributeName: NSColor.blackColor()]
let attrStr = NSMutableAttributedString(string: "my string", attributes: attributes)
let area = NSMakeRange(0, attrStr.length)
if let font = NSFont(name: "Helvetica Neue Light", size: 16) {
attrStr.addAttribute(NSFontAttributeName, value: font, range: area)
textView.textStorage?.appendAttributedString(attrStr)
}
I've been creating a MacOS app and am having trouble styling the font of an NSSearchField (named searchField). My code so far is as follows:
Declared at top of single main viewController class:
let normalTextStyle = NSFont(name: "PT Mono", size: 14.0)
let backgroundColour = NSColor(calibratedHue: 0.6,
saturation: 0.5,
brightness: 0.2,
alpha: 1.0)
let normalTextColour = NSColor(calibratedHue: 0.5,
saturation: 0.1,
brightness: 0.9,
alpha: 1.0)
Declared in viewDidLoad:
searchField.backgroundColor = backgroundColour
searchField.textColor = normalTextColour
searchField.font = normalTextStyle
searchField.centersPlaceholder = false
searchField.currentEditor()?.font = normalTextStyle
let attrStr = NSMutableAttributedString(string: "Search...",
attributes: [NSForegroundColorAttributeName: normalTextColour])
searchField.placeholderAttributedString = attrStr
Generally this works except in one condition: when the search field has focus but no search term has been entered. In this case the placeholder text has the correct colour but the font seems to return to the default (Helvetica 12 point?). As soon as something is typed in or the field loses focus, then the correct font is used once more.
I have tried with no luck looking through the Apple docs for some kind of font or colour settings not currently being set. I have fiddled about with all the font setting I could find in the interface builder, including cocoa bindings and the normal settings in the inspector.
Do I need to set some value of the currentEditor? I am guessing not because the font is changed once text is entered.. I am stuck - can anyone help?
EDIT: I've now tried with an NSTextField and the results are the same. Does anyone have any ideas?
I eventually managed to find an answer. I created a new class TitleTextFormatter of type Formatter, which is 'is intended for subclassing. A custom formatter can restrict the input and enhance the display of data in novel ways'. All I needed to do was override certain default functions to get what I needed:
import Cocoa
class TitleTextFormatter: Formatter {
override func string(for obj: Any?) -> String? {
/*
* this function receives the object it is attached to.
* in my case it only ever receives an NSConcreteAttributedString
* and returns a plain string to be formatted by other functions
*/
var result: String? = nil
if let attrStr = obj as? NSAttributedString {
result = attrStr.string
}
return result
}
override func getObjectValue( _ obj: AutoreleasingUnsafeMutablePointer<AnyObject?>?,
for string: String,
errorDescription error: AutoreleasingUnsafeMutablePointer<NSString?>?) -> Bool {
/*
* this function in general is overridden to provide an object created
* from the input string. in this instance, all I want is an attributed string
*/
let titleParagraphStyle = NSMutableParagraphStyle()
titleParagraphStyle.alignment = .center
let titleAttributes = [NSAttributedStringKey.foregroundColor: NSColor.mainText,
NSAttributedStringKey.font: NSFont.titleText,
NSAttributedStringKey.paragraphStyle: titleParagraphStyle]
let titleAttrStr = NSMutableAttributedString(string: string,
attributes: titleAttributes)
obj?.pointee = titleAttrStr
return true
}
override func attributedString(for obj: Any,
withDefaultAttributes attrs: [NSAttributedStringKey : Any]? = nil) -> NSAttributedString? {
/*
* is overridden to show that an attributed string is created from the
* formatted object. this happens to duplicate what the previous function
* does, only because the object I want to create from string is an
* attributed string
*/
var titleAttrStr: NSMutableAttributedString?
if let str = string(for: obj) {
let titleParagraphStyle = NSMutableParagraphStyle()
titleParagraphStyle.alignment = .center
let titleAttributes = [NSAttributedStringKey.foregroundColor: NSColor.mainText,
NSAttributedStringKey.font: NSFont.titleText,
NSAttributedStringKey.paragraphStyle: titleParagraphStyle]
titleAttrStr = NSMutableAttributedString(string: str,
attributes: titleAttributes)
}
return titleAttrStr
}
}
and then in viewDidLoad I added the following:
let titleTextFormatter = TitleTextFormatter()
titleTextField.formatter = titleTextFormatter