I am wanting to find the current paragraph that the user is typing in(where the caret is). Example: Here it would be in the 2nd Paragraph.
I know I can separate paragraphs using: let components = textView.text.components(separatedBy: "\n") but I am unsure how I would run a check for the current editing paragraph. Any ideas?
Here is one approach...
Get the Y position of the caret (insertion point). Then, loop through an enumeration of the paragraphs in the textView, comparing their bounding rects to the caret position:
extension UITextView {
func boundingFrame(ofTextRange range: Range<String.Index>?) -> CGRect? {
guard let range = range else { return nil }
let length = range.upperBound.encodedOffset-range.lowerBound.encodedOffset
guard
let start = position(from: beginningOfDocument, offset: range.lowerBound.encodedOffset),
let end = position(from: start, offset: length),
let txtRange = textRange(from: start, to: end)
else { return nil }
return selectionRects(for: txtRange).reduce(CGRect.null) { $0.union($1.rect) }
}
}
// return value will be Zero-based index of the paragraphs
// if the textView has no text, return -1
#objc func getParagraphIndex(in textView: UITextView) -> Int {
// this will make sure the the text container has updated
theTextView.layoutManager.ensureLayout(for: theTextView.textContainer)
// make sure we have some text
guard let str = theTextView.text else { return -1 }
// get the full range
let textRange = str.startIndex..<str.endIndex
// we want to enumerate by paragraphs
let opts:NSString.EnumerationOptions = .byParagraphs
var caretYPos = CGFloat(0)
if let selectedTextRange = theTextView.selectedTextRange {
caretYPos = theTextView.caretRect(for: selectedTextRange.start).origin.y + 4
}
var pIndex = -1
var i = 0
// loop through the paragraphs, comparing the caret Y position to the paragraph bounding rects
str.enumerateSubstrings(in: textRange, options: opts) {
(substring, substringRange, enclosingRange, b) in
// get the bounding rect for the sub-rects in each paragraph
if let boundRect = self.theTextView.boundingFrame(ofTextRange: substringRange) {
if caretYPos > boundRect.origin.y && caretYPos < boundRect.origin.y + boundRect.size.height {
pIndex = i
b = true
}
i += 1
}
}
return pIndex
}
Usage:
let paraIndex = getParagraphIndex(in myTextView)
Long time user, first time poster, so my apologies if I make any errors in presenting my question. I have been working on this for hours and I've decided it is time to ask the experts. I have also searched through every similar question that has been "answered" and work, which leads me to believe they are outdated.
I am attempting to grab the tapped word from a UITextview that would be used later in the code. For example, there is a paragraph of words in the text view:
"The initial return on time investment is much smaller, due to him trading his upfront cost for sweat-equity in the company, but the potential long-term payout is much greater".
I would want to be able to tap on a word, e.g. 'investment', and run it through another function to define it. However simply tapping the word, crashes the program, and I do not receive the word tapped.
I implemented a tap gesture recognizer:
let tap = UITapGestureRecognizer(target: self, action: #selector(tapResponse(_:)))
tap.delegate = self
tvEditor.addGestureRecognizer(tap)
and then wrote the function: 2
func tapResponse(recognizer: UITapGestureRecognizer) {
let location: CGPoint = recognizer.locationInView(tvEditor)
let position: CGPoint = CGPointMake(location.x, location.y)
let tapPosition: UITextPosition = tvEditor.closestPositionToPoint(position)!
let textRange: UITextRange = tvEditor.tokenizer.rangeEnclosingPosition(tapPosition, withGranularity: UITextGranularity.Word, inDirection: 1)!
let tappedWord: String = tvEditor.textInRange(textRange)!
print("tapped word : %#", tappedWord)
}
Ideally, this should take the location from the tapped part of the Textview, take the position by taking the .x & .y, and then looking through the Textview at the point closest to the position, finding the Range enclosing the position with granularity (to return the word), and setting the contents as a String, which I am currently just printing to the console. However, on tapping the word, I receive this crash.3
along with "fatal error: unexpectedly found nil while unwrapping an Optional value" in the console.
Any help would be greatly appreciated. I may just be missing something simple, or it could be much more complicated.
Whenever the tapped received at the blank spaces between the words, tapPosition returned by the TextView can be nil nil.
Swift has new operator called optional ? which tells the compiler that the variable may have nil value. If you do not use ? after the variable name indicates that the variable can never have nil value.
In Swift, using ! operator means you are forcing the compiler to forcefully extract the value from the optional variable. So, in that case, if the value of the variable is nil, it will crash on forcing.
So, what is actually happening is
You are creating the variable let tapPosition: UITextPosition, let textRange: UITextRange and let tappedWord: String are not optional
return type of the method myTextView.closestPositionToPoint(position), tvEditor.textInRange(textRange) are optional variable UITextPosition?, String?
Assigning a value of optional variable to non optional variable requires !
The method is returning nil and you are forcing it to get the value ! lead to CRASH
What you can do
Before forcing any optional variable, just be sure that it has some value using
if variable != nil
{
print(variable!)
}
Correct method would be as
func tapResponse(recognizer: UITapGestureRecognizer) {
let location: CGPoint = recognizer.locationInView(myTextView)
let position: CGPoint = CGPointMake(location.x, location.y)
let tapPosition: UITextPosition? = myTextView.closestPositionToPoint(position)
if tapPosition != nil {
let textRange: UITextRange? = myTextView.tokenizer.rangeEnclosingPosition(tapPosition!, withGranularity: UITextGranularity.Word, inDirection: 1)
if textRange != nil
{
let tappedWord: String? = myTextView.textInRange(textRange!)
print("tapped word : ", tappedWord)
}
}
}
Swift 3.0 Answer - Working as of July 1st, 2016
In my ViewDidLoad() -
I use text from a previous VC, so my variable "theText" is already declared. I included a sample string that has been noted out.
//Create a variable of the text you wish to attribute.
let textToAttribute = theText // or "This is sample text"
// Break your string in to an array, to loop through it.
let textToAttributeArray = textToAttribute.componentsSeparatedByString(" ")
// Define a variable as an NSMutableAttributedString() so you can append to it in your loop.
let attributedText = NSMutableAttributedString()
// Create a For - In loop that goes through each word your wish to attribute.
for word in textToAttributeArray{
// Create a pending attribution variable. Add a space for linking back together so that it doesn't looklikethis.
let attributePending = NSMutableAttributedString(string: word + " ")
// Set an attribute on part of the string, with a length of the word.
let myRange = NSRange(location: 0, length: word.characters.count)
// Create a custom attribute to get the value of the word tapped
let myCustomAttribute = [ "Tapped Word:": word]
// Add the attribute to your pending attribute variable
attributePending.addAttributes(myCustomAttribute, range: myRange)
print(word)
print(attributePending)
//append 'attributePending' to your attributedText variable.
attributedText.appendAttributedString(attributePending) ///////
print(attributedText)
}
textView.attributedText = attributedText // Add your attributed text to textview.
Now we will add a tap gesture recognizer to register taps.
let tap = UITapGestureRecognizer(target: self, action: #selector(HandleTap(_:)))
tap.delegate = self
textView.addGestureRecognizer(tap) // add gesture recognizer to text view.
Now we declare a function under the viewDidLoad()
func HandleTap(sender: UITapGestureRecognizer) {
let myTextView = sender.view as! UITextView //sender is TextView
let layoutManager = myTextView.layoutManager //Set layout manager
// location of tap in myTextView coordinates
var location = sender.locationInView(myTextView)
location.x -= myTextView.textContainerInset.left;
location.y -= myTextView.textContainerInset.top;
// character index at tap location
let characterIndex = layoutManager.characterIndexForPoint(location, inTextContainer: myTextView.textContainer, fractionOfDistanceBetweenInsertionPoints: nil)
// if index is valid then do something.
if characterIndex < myTextView.textStorage.length {
// print the character index
print("Your character is at index: \(characterIndex)") //optional character index.
// print the character at the index
let myRange = NSRange(location: characterIndex, length: 1)
let substring = (myTextView.attributedText.string as NSString).substringWithRange(myRange)
print("character at index: \(substring)")
// check if the tap location has a certain attribute
let attributeName = "Tapped Word:" //make sure this matches the name in viewDidLoad()
let attributeValue = myTextView.attributedText.attribute(attributeName, atIndex: characterIndex, effectiveRange: nil) as? String
if let value = attributeValue {
print("You tapped on \(attributeName) and the value is: \(value)")
}
}
}
In addition to #AmitSingh answer, this is updated Swift 3.0 version:
func didTapTextView(recognizer: UITapGestureRecognizer) {
let location: CGPoint = recognizer.location(in: textView)
let position: CGPoint = CGPoint(x: location.x, y: location.y)
let tapPosition: UITextPosition? = textView.closestPosition(to: position)
if tapPosition != nil {
let textRange: UITextRange? = textView.tokenizer.rangeEnclosingPosition(tapPosition!, with: UITextGranularity.word, inDirection: 1)
if textRange != nil
{
let tappedWord: String? = textView.text(in: textRange!)
print("tapped word : ", tappedWord!)
}
}
}
The other code is the same as his.
Hope it helps!
How to convert character index from layoutManager to String scale in swift?
this is the code I'm using:
let touchPoint: CGPoint = gesture.locationOfTouch(0, inView: self.definitionLabel)
let index = layoutManager.characterIndexForPoint(touchPoint, inTextContainer: textContainer, fractionOfDistanceBetweenInsertionPoints: nil)
please don't tell me to use advanceBy() function on the first index of the string characterset since characters like ò count two in the scale of layoutManager but swift string counts theme once.
The index returned from the NSLayoutManager is "NSString based",
i.e. it is the number of UTF-16 code units from the start of the string
to the character at the given point. (So ò actually counts as
one, but Emojis 😀 count two and flags 🇧🇪 even count four.)
To convert that index to a valid Swift String index, you can use
the same approach as in https://stackoverflow.com/a/30404532/1187415:
let text = ... // the stored text
let i16 = text.utf16.startIndex.advancedBy(index, limit: text.utf16.endIndex)
// i16 is a String.UTF16View.Index
if let strIndex = String.Index(i16, within: text) {
// strIndex is a String.CharacterView.Index
let char = text[strIndex]
print(char)
}
Updated for Swift 5
Martin R's answer gave me the rough outline; here's working Swift 5 version. Mine is for a UITextView with Attributed Text but should work just as well with regular String and for UITextField and UILabel.
func handleTap(_ sender: UIGestureRecognizer) {
guard let textView = sender.view as? UITextView else { return }
guard let plaintext = textView.attributedText?.string else { return }
//guard let plaintext = textView.text else { return }
let location = sender.location(in: textView)
let charIndex = textView.layoutManager.characterIndex(for: location, in: textView.textContainer,
fractionOfDistanceBetweenInsertionPoints: nil)
if let strIndex = plaintext.utf16.index(plaintext.utf16.startIndex, offsetBy: charIndex, limitedBy: plaintext.utf16.endIndex) {
let char = plaintext[strIndex]
print("Character tapped was \(char)")
}
}
let textTap = UITapGestureRecognizer(target: self, action: #selector(handleTap))
textView.addGestureRecognizer(textTap)
I have the following string I would like to edit:
var someString = "I wan't this text {something I don't want}"
I would like to remove all the text contained in the two braces, no matter how long that text is. I have been using the follow code to remove a section of a String when I know the range:
extension String {
mutating func deleteCharactersInRange(range: NSRange) {
let mutableSelf = NSMutableString(string: self)
mutableSelf.deleteCharactersInRange(range)
self = mutableSelf
}
}
However, I do not know the range in my problem. Any ideas?
Working with strings and ranges can be quite challenging when mixing NSString and NSRange with Swift's String and Range.
Here is a pure Swift solution.
var someString = "I wan't this text {something I don't want}"
let rangeOpenCurl = someString.rangeOfString("{")
let rangeCloseCurl = someString.rangeOfString("}")
if let startLocation = rangeOpenCurl?.startIndex,
let endLocation = rangeCloseCurl?.endIndex {
someString.replaceRange(startLocation ..< endLocation, with: "")
}
With a RegEx pattern to match anything enclosed with curly brackets:
var sourceString: String = "I wan\'t this text {something I don't want}"
let destinationString = sourceString.stringByReplacingOccurrencesOfString("\\{(.*?)\\}", withString: "", options: .RegularExpressionSearch)
print(destinationString)
This will print "I wan't this text " without the double quotes.
extension String {
func getCurlyBraceRanges() -> [NSRange] {
var results = [NSRange]()
var leftCurlyBrace = -1
for index in 0..<self.characters.count {
let char = self[self.startIndex.advancedBy(index)]
if char == Character("{") {
leftCurlyBrace = index
} else if char == Character("}") {
if leftCurlyBrace != -1 {
results.append(NSRange(location: leftCurlyBrace, length: index - leftCurlyBrace + 1))
leftCurlyBrace = -1
}
}
}
return results
}
mutating func deleteCharactersInRange(range: NSRange) {
let mutableSelf = NSMutableString(string: self)
mutableSelf.deleteCharactersInRange(range)
self = String(mutableSelf)
}
mutating func deleteCharactersInRanges(ranges: [NSRange]) {
var tmpString = self
for i in (0..<ranges.count).reverse() {
tmpString.deleteCharactersInRange(ranges[i])
print(tmpString)
}
self = tmpString
}
}
var testString = "I wan't this text {something I don't want}"
testString.deleteCharactersInRanges(testString.getCurlyBraceRanges())
Output: "I wan't this text "
I need to create a String with format which can convert Int, Int64, Double, etc types into String. Using Objective-C, I can do it by:
NSString *str = [NSString stringWithFormat:#"%d , %f, %ld, %#", INT_VALUE, FLOAT_VALUE, DOUBLE_VALUE, STRING_VALUE];
How to do same but in Swift?
I think this could help you:
import Foundation
let timeNow = time(nil)
let aStr = String(format: "%#%x", "timeNow in hex: ", timeNow)
print(aStr)
Example result:
timeNow in hex: 5cdc9c8d
nothing special
let str = NSString(format:"%d , %f, %ld, %#", INT_VALUE, FLOAT_VALUE, LONG_VALUE, STRING_VALUE)
let str = "\(INT_VALUE), \(FLOAT_VALUE), \(DOUBLE_VALUE), \(STRING_VALUE)"
Update: I wrote this answer before Swift had String(format:) added to it's API. Use the method given by the top answer.
No NSString required!
String(format: "Value: %3.2f\tResult: %3.2f", arguments: [2.7, 99.8])
or
String(format:"Value: %3.2f\tResult: %3.2f", 2.7, 99.8)
I would argue that both
let str = String(format:"%d, %f, %ld", INT_VALUE, FLOAT_VALUE, DOUBLE_VALUE)
and
let str = "\(INT_VALUE), \(FLOAT_VALUE), \(DOUBLE_VALUE)"
are both acceptable since the user asked about formatting and both cases fit what they are asking for:
I need to create a string with format which can convert int, long, double etc. types into string.
Obviously the former allows finer control over the formatting than the latter, but that does not mean the latter is not an acceptable answer.
First read Official documentation for Swift language.
Answer should be
var str = "\(INT_VALUE) , \(FLOAT_VALUE) , \(DOUBLE_VALUE), \(STRING_VALUE)"
println(str)
Here
1) Any floating point value by default double
EX.
var myVal = 5.2 // its double by default;
-> If you want to display floating point value then you need to explicitly define such like a
EX.
var myVal:Float = 5.2 // now its float value;
This is far more clear.
let INT_VALUE=80
let FLOAT_VALUE:Double= 80.9999
let doubleValue=65.0
let DOUBLE_VALUE:Double= 65.56
let STRING_VALUE="Hello"
let str = NSString(format:"%d , %f, %ld, %#", INT_VALUE, FLOAT_VALUE, DOUBLE_VALUE, STRING_VALUE);
println(str);
The accepted answer is definitely the best general solution for this (i.e., just use the String(format:_:) method from Foundation) but...
If you are running Swift ≥ 5, you can leverage the new StringInterpolationProtocol protocol to give yourself some very nice syntax sugar for common string formatting use cases in your app.
Here is how the official documentation summarizes this new protocol:
Represents the contents of a string literal with interpolations while it’s being built up.
Some quick examples:
extension String.StringInterpolation {
/// Quick formatting for *floating point* values.
mutating func appendInterpolation(float: Double, decimals: UInt = 2) {
let floatDescription = String(format: "%.\(decimals)f%", float)
appendLiteral(floatDescription)
}
/// Quick formatting for *hexadecimal* values.
mutating func appendInterpolation(hex: Int) {
let hexDescription = String(format: "0x%X", hex)
appendLiteral(hexDescription)
}
/// Quick formatting for *percents*.
mutating func appendInterpolation(percent: Double, decimals: UInt = 2) {
let percentDescription = String(format: "%.\(decimals)f%%", percent * 100)
appendLiteral(percentDescription)
}
/// Formats the *elapsed time* since the specified start time.
mutating func appendInterpolation(timeSince startTime: TimeInterval, decimals: UInt = 2) {
let elapsedTime = CACurrentMediaTime() - startTime
let elapsedTimeDescription = String(format: "%.\(decimals)fs", elapsedTime)
appendLiteral(elapsedTimeDescription)
}
}
which could be used as:
let number = 1.2345
"Float: \(float: number)" // "Float: 1.23"
"Float: \(float: number, decimals: 1)" // "Float: 1.2"
let integer = 255
"Hex: \(hex: integer)" // "Hex: 0xFF"
let rate = 0.15
"Percent: \(percent: rate)" // "Percent: 15.00%"
"Percent: \(percent: rate, decimals: 0)" // "Percent: 15%"
let startTime = CACurrentMediaTime()
Thread.sleep(forTimeInterval: 2.8)
"∆t was \(timeSince: startTime)" // "∆t was 2.80s"
"∆t was \(timeSince: startTime, decimals: 0)" // "∆t was 3s"
This was introduced by SE-0228, so please be sure to read the original proposal for a deeper understanding of this new feature. Finally, the protocol documentation is helpful as well.
I know a lot's of time has passed since this publish, but I've fallen in a similar situation and create a simples class to simplify my life.
public struct StringMaskFormatter {
public var pattern : String = ""
public var replecementChar : Character = "*"
public var allowNumbers : Bool = true
public var allowText : Bool = false
public init(pattern:String, replecementChar:Character="*", allowNumbers:Bool=true, allowText:Bool=true)
{
self.pattern = pattern
self.replecementChar = replecementChar
self.allowNumbers = allowNumbers
self.allowText = allowText
}
private func prepareString(string:String) -> String {
var charSet : NSCharacterSet!
if allowText && allowNumbers {
charSet = NSCharacterSet.alphanumericCharacterSet().invertedSet
}
else if allowText {
charSet = NSCharacterSet.letterCharacterSet().invertedSet
}
else if allowNumbers {
charSet = NSCharacterSet.decimalDigitCharacterSet().invertedSet
}
let result = string.componentsSeparatedByCharactersInSet(charSet)
return result.joinWithSeparator("")
}
public func createFormattedStringFrom(text:String) -> String
{
var resultString = ""
if text.characters.count > 0 && pattern.characters.count > 0
{
var finalText = ""
var stop = false
let tempString = prepareString(text)
var formatIndex = pattern.startIndex
var tempIndex = tempString.startIndex
while !stop
{
let formattingPatternRange = formatIndex ..< formatIndex.advancedBy(1)
if pattern.substringWithRange(formattingPatternRange) != String(replecementChar) {
finalText = finalText.stringByAppendingString(pattern.substringWithRange(formattingPatternRange))
}
else if tempString.characters.count > 0 {
let pureStringRange = tempIndex ..< tempIndex.advancedBy(1)
finalText = finalText.stringByAppendingString(tempString.substringWithRange(pureStringRange))
tempIndex = tempIndex.advancedBy(1)
}
formatIndex = formatIndex.advancedBy(1)
if formatIndex >= pattern.endIndex || tempIndex >= tempString.endIndex {
stop = true
}
resultString = finalText
}
}
return resultString
}
}
The follow link send to the complete source code:
https://gist.github.com/dedeexe/d9a43894081317e7c418b96d1d081b25
This solution was base on this article:
http://vojtastavik.com/2015/03/29/real-time-formatting-in-uitextfield-swift-basics/
There is a simple solution I learned with "We <3 Swift" if you can't either import Foundation, use round() and/or does not want a String:
var number = 31.726354765
var intNumber = Int(number * 1000.0)
var roundedNumber = Double(intNumber) / 1000.0
result: 31.726
Use this following code:
let intVal=56
let floatval:Double=56.897898
let doubleValue=89.0
let explicitDaouble:Double=89.56
let stringValue:"Hello"
let stringValue="String:\(stringValue) Integer:\(intVal) Float:\(floatval) Double:\(doubleValue) ExplicitDouble:\(explicitDaouble) "
The beauty of String(format:) is that you can save a formatting string and then reuse it later in dozen of places. It also can be localized in this single place. Where as in case of the interpolation approach you must write it again and again.
Simple functionality is not included in Swift, expected because it's included in other languages, can often be quickly coded for reuse. Pro tip for programmers to create a bag of tricks file that contains all this reuse code.
So from my bag of tricks we first need string multiplication for use in indentation.
#inlinable func * (string: String, scalar: Int) -> String {
let array = [String](repeating: string, count: scalar)
return array.joined(separator: "")
}
and then the code to add commas.
extension Int {
#inlinable var withCommas:String {
var i = self
var retValue:[String] = []
while i >= 1000 {
retValue.append(String(format:"%03d",i%1000))
i /= 1000
}
retValue.append("\(i)")
return retValue.reversed().joined(separator: ",")
}
#inlinable func withCommas(_ count:Int = 0) -> String {
let retValue = self.withCommas
let indentation = count - retValue.count
let indent:String = indentation >= 0 ? " " * indentation : ""
return indent + retValue
}
}
I just wrote this last function so I could get the columns to line up.
The #inlinable is great because it takes small functions and reduces their functionality so they run faster.
You can use either the variable version or, to get a fixed column, use the function version. Lengths set less than the needed columns will just expand the field.
Now you have something that is pure Swift and does not rely on some old objective C routine for NSString.
Since String(format: "%s" ...) is crashing at run time, here is code to allow write something like "hello".center(42); "world".alignLeft(42):
extension String {
// note: symbol names match to nim std/strutils lib:
func align (_ boxsz: UInt) -> String {
self.withCString { String(format: "%\(boxsz)s", $0) }
}
func alignLeft (_ boxsz: UInt) -> String {
self.withCString { String(format: "%-\(boxsz)s", $0) }
}
func center (_ boxsz: UInt) -> String {
let n = self.count
guard boxsz > n else { return self }
let padding = boxsz - UInt(n)
let R = padding / 2
guard R > 0 else { return " " + self }
let L = (padding%2 == 0) ? R : (R+1)
return " ".withCString { String(format: "%\(L)s\(self)%\(R)s", $0,$0) }
}
}
Success to try it:
var letters:NSString = "abcdefghijkl"
var strRendom = NSMutableString.stringWithCapacity(strlength)
for var i=0; i<strlength; i++ {
let rndString = Int(arc4random() % 12)
//let strlk = NSString(format: <#NSString#>, <#CVarArg[]#>)
let strlk = NSString(format: "%c", letters.characterAtIndex(rndString))
strRendom.appendString(String(strlk))
}