Limiting user's text entry to the height of the UITextView - ios

I'm working with a UITextView and I want to make it so that once the user has filled the UITextView (you make it in storyboard, and these dimensions the user is not allowed to type outside of) the user cannot type anymore text. Basically, whats happening now is even if it looks like it's filled and I keep typing its like a never-ending text box which you can't see. What I assume is the dimensions you make it in storyboard is the only space you see text in.
Can someone help me?
http://www.prntscr.com/671n1u

You can use the UITextViewDelegate shouldChangeTextInRange: method to limit the text entry to the height of the text view:
func textView(textView: UITextView, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool {
// Combine the new text with the old
let combinedText = (textView.text as NSString).stringByReplacingCharactersInRange(range, withString: text)
// Create attributed version of the text
let attributedText = NSMutableAttributedString(string: combinedText)
attributedText.addAttribute(NSFontAttributeName, value: textView.font, range: NSMakeRange(0, attributedText.length))
// Get the padding of the text container
let padding = textView.textContainer.lineFragmentPadding
// Create a bounding rect size by subtracting the padding
// from both sides and allowing for unlimited length
let boundingSize = CGSizeMake(textView.frame.size.width - padding * 2, CGFloat.max)
// Get the bounding rect of the attributed text in the
// given frame
let boundingRect = attributedText.boundingRectWithSize(boundingSize, options: NSStringDrawingOptions.UsesLineFragmentOrigin, context: nil)
// Compare the boundingRect plus the top and bottom padding
// to the text view height; if the new bounding height would be
// less than or equal to the text view height, append the text
if (boundingRect.size.height + padding * 2 <= textView.frame.size.height){
return true
}
else {
return false
}
}

Related

Change only fontsize of NSAttributedString

I have a NSAttributedString that was loaded from a RTF file, so it already holds several font-attributes for different ranges.
Now I want to adapt the font size to the screensize of the device, but when I add a whole new font attribute with a new size, the other fonts disappear.
Is there a way to change only the font size for the whole string?
If you only want to change the size of any given font found in the attributed string then you can do:
let newStr = someAttributedString.mutableCopy() as! NSMutableAttributedString
newStr.beginEditing()
newStr.enumerateAttribute(.font, in: NSRange(location: 0, length: newStr.string.utf16.count)) { (value, range, stop) in
if let oldFont = value as? UIFont {
let newFont = oldFont.withSize(20) // whatever size you need
newStr.addAttribute(.font, value: newFont, range: range)
}
}
newStr.endEditing()
print(newStr)
This will keep all other attributes in place.
If you want to replace all fonts in a given attributed string with a single font of a given size but keep all other attributes such as bold and italic, see:
NSAttributedString, change the font overall BUT keep all other attributes?

Read/see More at the end of the label

I am trying to create a read more button at the end of my label. I want it to display 3 lines by default. I am coding in swift not objective c. Only when the user clicks the read more part of the label, should the label expand. It should look and work exactly like it does on instagram except on Instagram, it is in a tableview cell. My label and read more button will be in a scrollview. I have managed to get the expanding and contracting part working by adjusting the number of lines property of the label.
if descriptionLabel.numberOfLines == 0{
descriptionLabel.numberOfLines = 3
}else {
descriptionLabel.numberOfLines = 0
}
descriptionLabel.lineBreakMode = NSLineBreakMode.byWordWrapping
I am having problems with putting a "...more" at the end of the label and cutting the text off at the right place. I have looked at other people's responses to similar questions but nothing seems to work properly.
I can put a button over the last line of text so making the see more part of the label clickable also isn't the problem. The problem I am having is truncating the text at the right place and placing the see more text at the right place so that it displays.
I also want the read more button to only appear when it is necessary. I don't want to it appear when there are only 1-3 lines of text. This is also something I am having issues with.
I can't use this https://github.com/apploft/ExpandableLabel because it does not support scrollviews just tableviews.
the swift solution here didn't work: Add "...Read More" to the end of UILabel. It crashed the app.
Finally, the read more button should be in line with the last line of text and at the end of it. It would be an added benefit it this worked in a tableview cell as well!
I found ReadMoreTextView in Github, which is based on UITextView. The key method in this library is the following:
private func characterIndexBeforeTrim(range rangeThatFits: NSRange) -> Int {
if let text = attributedReadMoreText {
let readMoreBoundingRect = attributedReadMoreText(text: text, boundingRectThatFits: textContainer.size)
let lastCharacterRect = layoutManager.boundingRectForCharacterRange(range: NSMakeRange(NSMaxRange(rangeThatFits)-1, 1), inTextContainer: textContainer)
var point = lastCharacterRect.origin
point.x = textContainer.size.width - ceil(readMoreBoundingRect.size.width)
let glyphIndex = layoutManager.glyphIndex(for: point, in: textContainer, fractionOfDistanceThroughGlyph: nil)
let characterIndex = layoutManager.characterIndexForGlyph(at: glyphIndex)
return characterIndex - 1
} else {
return NSMaxRange(rangeThatFits) - readMoreText!.length
}
}
To display text like "xxxx...Read More", the library
Get how many characters could be display in the UITextView: Use NSLayoutManager.characterRange(forGlyphRange:, actualGlyphRange:)
Get the position of the last visible character and the width of "...Read More": Use NSLayoutManager.boundingRect(forGlyphRange glyphRange: NSRange, in container: NSTextContainer)
Get the character index before trimming: Use NSLayoutManager.characterIndexForGlyph(at glyphIndex: Int)
Replace text which should be trimmed with "...Read More": UITextStorage.replaceCharacters(in range: NSRange, with attrString: NSAttributedString)
Please check :
func addSeeMore(str: String, maxLength: Int) -> NSAttributedString {
var attributedString = NSAttributedString()
let index: String.Index = str.characters.index(str.startIndex, offsetBy: maxLength)
let editedText = String(str.prefix(upTo: index)) + "... See More"
attributedString = NSAttributedString(string: editedText)
return attributedString
}
You can use like :
let str = "Lorem Ipsum is simply dummy text of the printing and typesetting industry."
descriptionLabel.attributedText = addSeeMore(str: str, maxLength: 20)
// Output : Lorem Ipsum is simpl... See More

iOS Swift Relative font size

I have a UITextView, and I want to change its font size.
however, I want it to change relatively since it pulls from a file that has multiple font sizes in it and I want it to change accordingly.
for example, I have a word in font size 36 and one in font size 12 and I want to scale them by 0.75% to 27 and 9 respectively.
If I try:
textview.font = UIFont(name: textview.font.fontName, size: 20)
it will only change the entire UITextView font size.
thanks!
You can use this extension:
extension NSAttributedString {
#warn_unused_result
func scaleBy(scale: CGFloat) -> NSAttributedString {
let scaledAttributedString = NSMutableAttributedString(attributedString: self)
scaledAttributedString.enumerateAttribute(NSFontAttributeName, inRange: NSRange(location: 0, length: scaledAttributedString.length), options: NSAttributedStringEnumerationOptions(rawValue: 0)) { (value, range, _) in
if let oldFont = value as? UIFont {
let newFont = oldFont.fontWithSize(oldFont.pointSize * scale)
scaledAttributedString.removeAttribute(NSFontAttributeName, range: range)
scaledAttributedString.addAttribute(NSFontAttributeName, value: newFont, range: range)
}
}
return scaledAttributedString
}
}
Then just call something like:
textField.attributedText = textField.attributedText!.scaleBy(0.5)
Example:
You would have to write (or find) a parser for the rich text format file that could extract the font size data for each text element (I think this would be the \fsN tags in most cases) and then use that number (multiplied by 0.75) to set the size of each word or phrase individually. You could use an attributed string if the differently sized words need to be recombined into a single string, but that wouldn't be necessary if each word or phrase was in a separate label.
Personally, I would disregard the font sizes of the source data and impose a layout within the app that looks nice, if that's an option.

Disable "..." truncating for a UITextField

I've been reviewing the documentation for UITextField and its options are much more limited than the UITextView.
I've run into a situation where I need to handle truncating the text by forcing the bounding box to be bigger so no truncation exists.
I cannot just use .adjustsFontSizeToFitWidth because this event is only allowed when the text box is at screen width. The truncation is happening when it's not full screen length.
Right now when the user types, I log each keystroke and make sure the UITextFields box expands to fit the text. However if I use a large font, the text is getting cut off still:
"THIS IS LARGE TEXT GETTING CUT O..."
Currently I log each keystroke and run this code to size it:
func adjustFrameWidthToFitText()
{
var size = sizeThatFits(CGSizeMake(CGFloat.max,height))
frame = CGRectMake(frame.origin.x, frame.origin.y, size.width + 7, frame.height)
}
However I still get the ... cut off in some places. Is there anyway to tell if the text is being truncated and override the behaviour causing said truncation?
(Solutions in Swift & Obj-c welcome!)
Based on the answer below I tried:
func adjustFrameWidthToFitText()
{
var fontSize = font.pointSize
var atr = [NSFontAttributeName:font]
var textSize = NSString(string: text).sizeWithAttributes(atr)
frame = CGRectMake(frame.origin.x, frame.origin.y, textSize.width, frame.height)
}
But there is still truncation
extension String {
func sizeWithAttributes(atr: NSDictionary) -> CGSize {
return NSString(string: self).sizeWithAttributes(atr)
}
}
let size = textView.text.sizeWithAttributes([NSFontAttribute:textView.font])
This will return the exact size for the string including '\n' characters.
The you can use the size however you want.
ADDED
Also when I was using CATextLayer I had to add this to the attributes to get the rows, havent tested on UITextView or field though:
let style = NSMutableParagraphStyle()
style.lineHeightMultiple = 1.05
..., NSParagraphStyleAttributeName:style])
After much digging I found the root cause, and a shortcut.
Shortcut first:
func adjustFrameWidthToFitText()
{
var size = intrinsicContentSize()
frame = CGRectMake(frame.origin.x, frame.origin.y, size.width, frame.height)
}
This gives me the size of the textfield.
The problem with my code was I was calculating the resize event BEFORE the character was added to the text. So my bounds were always being calculated before the latest keystroke was added to the string.
When I changed my logic
public func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool
{
adjustFrameWidthToFitText()
return true
}
To
textFieldDidEndEditing(_:)
{
adjustFrameWidthToFitText()
}
It works.
Voila!

UITextField - Remove Ellipses on Text Overflow

I have a UItextfieldthat holds a person's middle name. I only want it to display the first initial, which it does, but i want it to hold their entire name. It's only large enough to show the one initial, but it adds that ellipses (...) after the letter.Is it possible to remove those when a uitextfield overflows? I haven't found anything online regarding someone with the same issue.
Thankyou for your help
I do see this truncation when the text field resigns first responder. I fixed this by setting the lineBreakMode in the NSParagraphStyle attribute to .byClipping. I happened to be using a subclass of UITextField so I overrode resignFirstResponder() to do this. My textField starts out empty so there is no attributedString to start with in viewDidLoad.
override func resignFirstResponder() -> Bool {
guard let newAttributedText = (attributedText?.mutableCopy() as? NSMutableAttributedString) else {
return super.resignFirstResponder()
}
let paragraphStyle = NSMutableParagraphStyle()
paragraphStyle.lineBreakMode = .byClipping
newAttributedText.addAttribute(NSAttributedString.Key.paragraphStyle, value: paragraphStyle, range: NSRange(location: 0, length: attributedText?.length ?? 0))
attributedText = newAttributedText
return super.resignFirstResponder()
}
This might not work if you set the text in code. In that case, you might want to set the lineBreak mode in a common function that you call from both the override of resignFirstResponder() and after setting the text in code. You could make a set(text: String?) function and call the common function from there.
A UITextField shouldn't be truncating the text (because you can usually scroll/select that UI element).
A UILabel will truncate by default, you can set it to clip instead.

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