Make text matched with NSRegularExpression clickable in UITextView - ios

I have a UITextView and using NSRegularExpression. I'm finding names in my text view. So I'm able to highlight matches using this code:
for match in matches as [NSTextCheckingResult] {
let matchRange = match.range
attributedText.addAttribute(NSStrokeColorAttributeName, value: UIColor.blueColor(), range: matchRange)
}
I want to make it clickable and pass its text to a new view controller. Or maybe change it to a UIButton with the same text and add a segue to the new view controller. I'm not sure how to do it correctly.

UITextView doesn't really have functionality for that. You could try your UIButton approach but you'll have trouble with links that wrap on multiple lines.
Two possible solutions:
You may be able to force its URL handling functionality to do what you want - see this question. This will depend on your NSRegularExpression.
You might want to try replacing your text view with TTTAttributedLabel or a similar third-party library that handles this for you. I think this is the most flexible option, and my recommended approach.

For future googlers, you could use NSLinkAttributeName
attributedText.addAttribute(NSLinkAttributeName, value: "\(your_value)", range: matchRange)

Related

UILabel wrong word wrap in iOS 11

I have problem with application using XIBs without autolayout. I don't know if this is important information.
I have UILabel with 2 lines using word wrap. In iOS 10 word wrap was working correctly, and first line contained one word + special character, for example ampersand. Example:
Then on iOS 11 word wrap is working somehow wrong and puts ampresand to the second line:
This is problematic as longer words, that normally fitted on second line now are not being shown correctly. Any idea what has changed? I know about safeArea but it doesn't look like reason. Any ideas how to move that ampersand to the top where is plenty of space for it?
Rest of the settings:
This is a change by Apple to prevent widowed lines. From a design perspective, it is preferred to avoid having a single word on a line of text. UILabel now breaks the line in a way that the second line of text always has at least 2 words on it.
See the answer below for an option to disable it.
Also here's a good article about "widowed" and "orphaned" text.
Since iOS 14 you can use lineBreakStrategy property of UILabel instance to control this behavior.
Available values are:
NSParagraphStyle.LineBreakStrategy() // none
NSParagraphStyle.LineBreakStrategy.pushOut
NSParagraphStyle.LineBreakStrategy.hangulWordPriority
NSParagraphStyle.LineBreakStrategy.standard
To disable this behavior using Swift:
if #available(iOS 14.0, *) {
label.lineBreakStrategy = []
}
// Alternatives
// label.lineBreakStrategy = NSParagraphStyle.LineBreakStrategy()
// label.lineBreakStrategy = .init(rawValue: 0)
// label.lineBreakStrategy = .init()
To make it work on lower iOS versions, you can use NSAttributedString:
let paragraphStyle = NSMutableParagraphStyle()
paragraphStyle.lineBreakStrategy = []
let attributedString = NSAttributedString(string: "Your text here", attributes: [
.paragraphStyle: paragraphStyle
])
let label = UILabel()
label.attributedText = attributedString
Objective-C:
if (#available(iOS 14.0, *)) {
label.lineBreakStrategy = NSLineBreakStrategyNone;
}
Launching the app with the arguments -NSAllowsDefaultLineBreakStrategy NO (an undocumented defaults setting) seems to force back to the old behavior. Alternatively, you can set NSAllowsDefaultLineBreakStrategy to NO in NSUserDefaults at startup (Apple registers a default of YES for that value when UILabel or the string drawing code is initialized, it appears, so you would need to register an overriding value after that, or insert it into the NSArgumentDomain, or just set the default persistently).
Apple may consider that private API and reject apps that use it; I'm not sure. I have not tried this in a shipping app. However, it does work in quick testing -- saw the setting in NSUserDefaults and found changing it altered the behavior.
This is not really an answer, but I want to add an illustration of how it is a general problem, not at all related to ampersands.
Both of these UILabels have identical width constraints, and the text is almost identical. But the second has the word wrap I would expect. The first is incorrect, the "about" can clearly stay on the first line.
A bit of a hack but you can add some zero width spaces to the end of the string to restore the old behaviour, without affecting the layout of the string otherwise that you'd get from normal spaces:
let zeroWidthSpace: Character = "\u{200B}"
let spacingForWordWrapping = String(repeating: zeroWidthSpace, count: 6)
label.text = "oneText & two" + spacingForWordWrapping
It seems that replacing the space before the ampersand with a non-breaking space (U+00A0) keeps the ampersand on the same line. Depending on how you are generating the text for the label, this might not be easy to automate (maybe you really do need the ampersand to be on the second line in some cases).
An option may be to use a UITextView instead -- that does not seem to have this behavior. If you set the NSTextContainer.lineFragmentPadding to 0, the textContainerInset to UIEdgeInsetsZero, and turn off all scrolling (scrollEnabled, bounces, scroll indicators, etc.) it will display similarly to a UILabel, though not with as much constraint flexibility. It's not a drop-in replacement, but in some situations it's acceptable.
As a simple (hacky) workaround, you can often get the correct behaviour with a UILabel by adding spaces at the end of your text. Using your example:
Wraps the new (undesired) way:
"oneText & two."
Wraps the old way:
"oneText & two. " (note the 2 extra spaces at the end of the string)
The obvious downside is if those extra spaces get forced to a new line by themselves, but for something simple like a title it's often enough.

Clear the attributed text of textfield from the IB clear button

I am not able to clear the attributed text of UITextField when the Interface Button clear button is triggered.
I have tried _textfield.attributedText = nil; but it doesn't work. What happens next is that the UI freezes and I am not able to interact with the UI anymore.
Moreover, the attributedText is not removed from the UI.
Note:
I can't use text property of textfield because I have an icon and a string inside my attributedText. Hence, I must use this.
Any help is much appreciated.
Ronak
Why don't you try setting an empty attributed string:
let emptyAttributedString = NSMutableAttributedString()
textView.attributedText = emptyAttributedString
Perhaps you could place this within the IB Action hooked to your clear button?

iOS Instagram Tags Text Layout? How Is It Done?

I've always been curious how instagram gets it's tags to layout fluidly and wanted to know what goes behind this functionality? To me, it seems like they're using UIButton's and just calculating placement of the buttons line by line? Is that right? Or is there a simpler method of doing it without having to manual calculate the placement of each tag line by line / or side by side given that multiple tag's width's fit together?
Or, are they using NSAttributedStrings?
Any ideas?
Here's an example of the layout I'm referring to.
Well, I'm currently working on NSAttributedString and UITextView to get all this working, and my current code can do it. So I'm going to explain a possible version of doing this.
Here are the tips and big steps, with iOS7:
NSAttributedString, in iOS7 has a new attribute : NSLinkAttributeName. You can add it to your NSAttributedString, and with a detection method (combining: how to make #key and #key clickable in IOS7 and Get word from tap in UITextView) you can manage it. That's for the general way of doing it. For previous version, you'll have to do a little more of work, but keeping this general idea.
But since, it only for hashtags, since you can detect the world behind the tap, you can do this: Detect what word has been tapped (see previous links), detect if this word has an hashtag, and if yes, you can do whatever action you want. You can play with a NSRegularExpression to know where are the hashtags, and know when to "color" them.
Here is a simplified way to do it using UITextView and NSAttributedString:
Use regular expressions to get character ranges for links.
Add link styling to the matched ranges.
Add custom attribute to range that references tap action to execute.
On touch, if index of character is inside a matched range, change the link formatting to highlight it and run the associated tap action.
How to get index of character at location in iOS7:
- (NSUInteger) getCharIndexAt: (CGPoint) location
{
NSLayoutManager *layoutManager = self.layoutManager;
NSUInteger characterIndex = NSNotFound;
characterIndex = [layoutManager characterIndexForPoint:location inTextContainer:self.textContainer fractionOfDistanceBetweenInsertionPoints:NULL];
return characterIndex;
}
Also check out WWDC 2013 intro to TextKit Demo
ios7 text utilities

How can I create a UITextField with ability display both text and emoticon?

I need create a UITextField, which can display both text and emoticon. Example, when I type : "abc :)", I will get "abc" text and smile-emoticon. So, how can I do that ?
My idea is create a UIView custom, every text is a UILabel, every emoticon is a UIImageView. But I see it is very complex. I want to find a simpler solution.
Thank for your support.
try pbrmojilable library
It may help you.

How to change shape of the UITextField?

I want to implement custom text fields. Here is a screenshot of what I want to implement:
So I have a UITableView with cells, and in each cell I have several text fields: one for date, one for name, one for theme, and one for text. But the UI requires theme and text to be next to each other (as can you see in the picture). I wanted to implement this as a single UITextField, but as far as I know, UITextField supports only one type of font. So maybe someone will give me a piece of advice how to implement the design shown in the screenshot — do I have to draw custom text fields, or are there simpler solutions? Any code samples or propositions would be helpful.
For iOS 6:
You can set a UITextField's attributed string:
#property(nonatomic,copy) NSAttributedString *attributedText;
I suggest to use a NSMutableAttributedString and to exploit polymorphism.
A mutable attributed string can hold vary attributes for each piece of the string. So you can add an attribute only for a certain range of the string with this method:
- (void)setAttributes:(NSDictionary *)attributes range:(NSRange)aRange;
For iOS 5:
Use directly this UITextField's property:
- (void)setAttributes:(NSDictionary *)attributes range:(NSRange)aRange;

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