I have a UITextField with a formatted string.
I can't figure out why a backspace press works fine for every character deletion except the first character?
My code:
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
let formatter = NumberFormatter()
formatter.usesGroupingSeparator = true
formatter.numberStyle = .decimal
formatter.decimalSeparator = "."
formatter.groupingSeparator = " "
let textString = textField.text ?? ""
guard let range = Range(range, in: textString) else { return false }
let updatedString = textString.replacingCharacters(in: range, with: string)
let completeString = updatedString.replacingOccurrences(of: formatter.groupingSeparator, with: "")
guard let value = Double(completeString) else { return false }
numberFromTextField = value
let formattedNumber = formatter.string(from: NSNumber(value: value)) ?? ""
textField.text = formattedNumber
return string == formatter.decimalSeparator
}
A gif with the problem behaviour: CLICK
Where is my error hides?
Related
I'm trying to format numbers in a UITextField consists of math equation string: "number + number".
At the moment I can type just a single number, then convert it to Double -> format with NSNumberFormatter -> convert back to String -> assign to textField.text:
The code:
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
let formatter = NumberFormatter()
formatter.numberStyle = .decimal
formatter.maximumFractionDigits = 2
formatter.locale = .current
formatter.roundingMode = .down
let numberString = textField.text ?? ""
guard let range = Range(range, in: numberString) else { return false }
let updatedString = numberString.replacingCharacters(in: range, with: string)
let correctDecimalString = updatedString.replacingOccurrences(of: formatter.decimalSeparator, with: ".")
let completeString = correctDecimalString.replacingOccurrences(of: formatter.groupingSeparator, with: "")
guard let value = Double(completeString) else { return false }
let formattedNumber = formatter.string(for: value)
textField.text = formattedNumber
return string == formatter.decimalSeparator
}
Now I want to add a calculation functionality and display a simple math equation in a textField as "number + number", but each number should be formatted as shown above. Example (but without formatting):
I can't properly implement that. The logic for me was: track the String each time new char inserts -> if it has math sign extract numbers -> convert them to Double -> format with NSNumberFormatter -> convert back to String -> construct a new String "number + number".
The code I tried:
if let firstString = completeString.split(separator: "+").first, let secondString = completeString.split(separator: "+").last {
guard let firstValue = Double(firstString) else { return false }
guard let secondValue = Double(secondString) else { return false }
let firstFormattedNumber = formatter.string(for: firstValue)
let secondFormattedNumber = formatter.string(for: secondValue)
textField.text = "\(firstFormattedNumber ?? "") + \(secondFormattedNumber ?? "")"
// another try
if completeString.contains("+") {
let stringArray = completeString.components(separatedBy: "+")
for character in stringArray {
print(character)
guard let value = Double(character) else { return false }
guard let formattedNumber = formatter.string(for: value) else { return false }
textField.text = "\(formattedNumber) + "
}
}
But it's not working properly. I tried to search but didn't find any similar questions.
Test project on GitHub
How can I format the numbers from such a string?
Here is how I was able to solve my question:
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
let formatter = NumberFormatter()
formatter.numberStyle = .decimal
formatter.maximumFractionDigits = 2
formatter.locale = .current
formatter.roundingMode = .down
//set of possible math operations
let symbolsSet = Set(["+","-","x","/"])
let numberString = textField.text ?? ""
guard let range = Range(range, in: numberString) else { return false }
let updatedString = numberString.replacingCharacters(in: range, with: string)
let correctDecimalString = updatedString.replacingOccurrences(of: formatter.decimalSeparator, with: ".")
let completeString = correctDecimalString.replacingOccurrences(of: formatter.groupingSeparator, with: "")
//receive math symbol user typed
let symbol = symbolsSet.filter(completeString.contains).first ?? ""
//receive number of symbols in a String. If user wants to type more than one math symbol - do not insert
let amountOfSymbols = completeString.filter({String($0) == symbol}).count
if amountOfSymbols > 1 { return false }
//receive numbers typed by user
let numbersArray = completeString.components(separatedBy: symbol)
//check for each number - if user wants to type more than one decimal sign - do not insert
for number in numbersArray {
let amountOfDecimalSigns = number.filter({$0 == "."}).count
if amountOfDecimalSigns > 1 { return false }
}
guard let firstNumber = Double(String(numbersArray.first ?? "0")) else { return true }
guard let secondNumber = Double(String(numbersArray.last ?? "0")) else { return true }
let firstFormattedNumber = formatter.string(for: firstNumber) ?? ""
let secondFormattedNumber = formatter.string(for: secondNumber) ?? ""
// if user typed math symbol - show 2 numbers and math symbol, if not - show just first typed number
textField.text = completeString.contains(symbol) ? "\(firstFormattedNumber)\(symbol)\(secondFormattedNumber)" : "\(firstFormattedNumber)"
return string == formatter.decimalSeparator
}
I want my textField to show 5.000,00 for instance, I manage to limit the characters that my user can type, but my currency isn't working. Also I am new to Swift, how do I get this currency to work out?
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
let formatter = NumberFormatter()
formatter.numberStyle = .currency
formatter.allowsFloats = true
formatter.currencyDecimalSeparator = ","
formatter.alwaysShowsDecimalSeparator = true
formatter.locale = Locale(identifier: "pt_BR")
formatter.currencyCode = "BRL"
formatter.maximumFractionDigits = 0
let currentText = textField.text ?? ","
guard let stringRange = Range(range, in: currentText) else { return false}
let updatedText = currentText.replacingCharacters(in: stringRange, with: string)
if let groupingSeparator = formatter.groupingSeparator {
if string == groupingSeparator {
return true
}
if let textWithoutGroupingSeparator = textField.text?.replacingOccurrences(of: groupingSeparator, with: "") {
var totalTextWithoutGroupingSeparators = textWithoutGroupingSeparator + string
if string.isEmpty { // pressed Backspace key
totalTextWithoutGroupingSeparators.removeLast()
}
if let numberWithoutGroupingSeparator = formatter.number(from: totalTextWithoutGroupingSeparators),
let formattedText = formatter.string(from: numberWithoutGroupingSeparator) {
textField.text = formattedText
return false
}
return updatedText.count <= 8
}
}
return true
}
I solve this with a string extension, previously I was using a function on my view controller, doing that way solve for me, you just have to change your locale and will works.
extension String {
// formatting text for currency textField
func currencyInputFormatting() -> String {
var number: NSNumber!
let formatter = NumberFormatter()
formatter.numberStyle = .decimal
formatter.locale = Locale(identifier: "pt_BR")
formatter.currencySymbol = ""
formatter.maximumFractionDigits = 2
formatter.minimumFractionDigits = 2
var amountWithPrefix = self
// remove from String: "$", ".", ","
let regex = try! NSRegularExpression(pattern: "[^0-9]", options: .caseInsensitive)
amountWithPrefix = regex.stringByReplacingMatches(in: amountWithPrefix, options: NSRegularExpression.MatchingOptions(rawValue: 0), range: NSMakeRange(0, self.count), withTemplate: "")
let double = (amountWithPrefix as NSString).doubleValue
number = NSNumber(value: (double / 100))
// if first number is 0 or all numbers were deleted
guard number != 0 as NSNumber else {
return ""
}
print(formatter.string(from: number))
return formatter.string(from: number)!
}
}
I am formatting a UITextField such that it becomes comma separated (Decimal style) while typing.
So 12345678 becomes 12,345,678
Now when I edit the UITextField, say I want to remove 5, at that time I tap after 5 and delete it but the cursor shifts to the end of the text immediately, that's after 8.
Here's my code which I have used to format the decimal while typing:
func checkTextField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
if ((string == "0" || string == "") && (textField.text! as NSString).range(of: ".").location < range.location) {
return true
}
let allowedCharacterSet = NSCharacterSet(charactersIn: "0123456789.").inverted
let filtered = string.components(separatedBy: allowedCharacterSet)
let component = filtered.joined(separator: "")
let isNumeric = string == component
if isNumeric {
let formatter = NumberFormatter()
formatter.numberStyle = .decimal
let newString = (textField.text! as NSString).replacingCharacters(in: range, with: string)
let numberWithOutCommas = newString.replacingOccurrences(of: ",", with: "")
let number = formatter.number(from: numberWithOutCommas)
if number != nil {
var formattedString = formatter.string(from: number!)
if string == "." && range.location == textField.text?.count {
formattedString = formattedString?.appending(".")
}
textField.text = formattedString
} else {
textField.text = nil
}
}
return false
}
It is called like this:
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
let textFieldText = (textField.text! as NSString).replacingCharacters(in: range, with: string)
let checkForCurrency = checkTextField(textField, shouldChangeCharactersIn: range, replacementString: string)
return checkForCurrency
}
I have tried the following but in vain :
Solution 1
Solution 2
What could the reason for cursor shift be?
It should be something like in this link
Any help would be appreciated!
update your custom function with :
func checkTextField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
let textFieldText = (textField.text! as NSString).replacingCharacters(in: range, with: string)
if ((string == "0" || string == "") && (textField.text! as NSString).range(of: ".").location < range.location) {
return true
}
var currentPosition = 0
if let selectedRange = textField.selectedTextRange {
currentPosition = textField.offset(from: textField.beginningOfDocument, to: selectedRange.start)
}
let allowedCharacterSet = NSCharacterSet(charactersIn: "0123456789.").inverted
let filtered = string.components(separatedBy: allowedCharacterSet)
let component = filtered.joined(separator: "")
let isNumeric = string == component
if isNumeric {
let formatter = NumberFormatter()
formatter.numberStyle = .decimal
let newString = (textField.text! as NSString).replacingCharacters(in: range, with: string)
let numberWithOutCommas = newString.replacingOccurrences(of: ",", with: "")
let number = formatter.number(from: numberWithOutCommas)
if number != nil {
var formattedString = formatter.string(from: number!)
if string == "." && range.location == textField.text?.count {
formattedString = formattedString?.appending(".")
}
textField.text = formattedString
if(textFieldText.count < formattedString?.count ?? 0){
currentPosition = currentPosition + 1
}
}else{
textField.text = nil
}
}
if(string == ""){
currentPosition = currentPosition - 1
}else{
currentPosition = currentPosition + 1
}
if let newPosition = textField.position(from: textField.beginningOfDocument, offset: currentPosition) {
textField.selectedTextRange = textField.textRange(from: newPosition, to: newPosition)
}
return false
}
How to set currency format E.g. 2,000,000.00 in swift on a textfield using swift 3.2 ? I am getting this response when in text field when i am entering amount in textfield
CharacterView(_core: Swift._StringCore(_baseAddress:
Optional(0x00000001c464e38a), _countAndFlags: 13835058055282163718,
_owner: Optional(₹ 75.33)), _coreOffset: 1)
My Code is:
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
// Construct the text that will be in the field if this change is accepted
switch string {
case "0","1","2","3","4","5","6","7","8","9":
currentString += string
formatCurrency(currentString)
default:
if string.characters.count == 0 && currentString.characters.count != 0 {
currentString = String(currentString.characters.dropLast())
formatCurrency(currentString)
}
}
return false }
func formatCurrency(_ string: String) {
print("format \(string)")
print(txtfieldamount.text!)
let formatter = NumberFormatter()
formatter.numberStyle = .currency
//formatter.locale = findLocaleByCurrencyCode("NGN")
let numberFromField = (NSString(string: currentString).doubleValue)/100
let temp = formatter.string(from: NSNumber(value: numberFromField))
self.txtfieldamount.text! = String(describing: temp!.characters.dropFirst())
print(txtfieldamount.text!)
}
I have a few textfields with decimal keyboards, I want to make them showing $ and comma ($1,222,000.00) in the screen. And also change the spacing of the text because when added comma it will be crowded.
for textField in self.numberTextField! as [UITextField] {
textField.keyboardType = .DecimalPad
textField.inputAccessoryView = keyboardToolbar
numberTextField is my collection of the textfields. Any help appreciated! Thanks a lot!
func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
let oldText = textField.text! as NSString
var newText = oldText.stringByReplacingCharactersInRange(range, withString: string) as NSString!
var newTextString = String(newText)
let digits = NSCharacterSet.decimalDigitCharacterSet()
var digitText = ""
for c in newTextString.unicodeScalars {
if digits.longCharacterIsMember(c.value) {
digitText.append(c)
}
}
let formatter = NSNumberFormatter()
formatter.numberStyle = NSNumberFormatterStyle.CurrencyStyle
formatter.locale = NSLocale(localeIdentifier: "en_US")
let numberFromField = (NSString(string: digitText).doubleValue)/100
newText = formatter.stringFromNumber(numberFromField)
textField.text = String(newText)
return false
}