feat(currencyTF): option to specify decimal places

Author: youjinp

Sources/SwiftUIKit/views/CurrencyTextField.swift

@@ -14,6 +14,7 @@ public struct CurrencyTextField: UIViewRepresentable {
  private var isResponder: Binding<Bool>?
  private var tag: Int
  private var alwaysShowFractions: Bool
+ private var numberOfDecimalPlaces: Int
 
  private var placeholder: String
 
@@ -44,7 +45,7 @@ public struct CurrencyTextField: UIViewRepresentable {
  isResponder: Binding<Bool>? = nil,
  tag: Int = 0,
  alwaysShowFractions: Bool = false,
- 
+ numberOfDecimalPlaces: Int = 2,
  font: UIFont? = nil,
  foregroundColor: UIColor? = nil,
  accentColor: UIColor? = nil,
@@ -65,6 +66,7 @@ public struct CurrencyTextField: UIViewRepresentable {
  self.isResponder = isResponder
  self.tag = tag
  self.alwaysShowFractions = alwaysShowFractions
+ self.numberOfDecimalPlaces = numberOfDecimalPlaces
 
  self.font = font
  self.foregroundColor = foregroundColor
@@ -92,7 +94,7 @@ public struct CurrencyTextField: UIViewRepresentable {
 
  // initial value
  if let v = self.value {
- textField.text = v.currencyFormat(decimalPlaces: self.alwaysShowFractions ? 2 : nil)
+ textField.text = v.currencyFormat(decimalPlaces: self.numberOfDecimalPlaces, forceShowDecimalPlaces: self.alwaysShowFractions)
  }
 
  // tag
@@ -170,7 +172,7 @@ public struct CurrencyTextField: UIViewRepresentable {
  }
 
  public func makeCoordinator() -> CurrencyTextField.Coordinator {
- Coordinator(value: $value, isResponder: self.isResponder, alwaysShowFractions: self.alwaysShowFractions, onReturn: self.onReturn){ flag in
+ Coordinator(value: $value, isResponder: self.isResponder, alwaysShowFractions: self.alwaysShowFractions, numberOfDecimalPlaces: self.numberOfDecimalPlaces, onReturn: self.onReturn){ flag in
  self.onEditingChanged(flag)
  }
  }
@@ -182,7 +184,7 @@ public struct CurrencyTextField: UIViewRepresentable {
  if self.value == nil {
  textField.text = nil
  } else {
- textField.text = self.value!.currencyFormat(decimalPlaces: self.alwaysShowFractions ? 2 : nil)
+ textField.text = self.value!.currencyFormat(decimalPlaces: self.numberOfDecimalPlaces, forceShowDecimalPlaces: self.alwaysShowFractions)
  }
  }
 
@@ -207,16 +209,24 @@ public struct CurrencyTextField: UIViewRepresentable {
  private var isResponder: Binding<Bool>?
  private var onReturn: ()->()
  private var alwaysShowFractions: Bool
+ private var numberOfDecimalPlaces: Int
  var internalValue: Double?
  var onEditingChanged: (Bool)->()
  var didBecomeFirstResponder = false
 
- init(value: Binding<Double?>, isResponder: Binding<Bool>?, alwaysShowFractions: Bool = false, onReturn: @escaping () -> Void = {}, onEditingChanged: @escaping (Bool) -> Void = { _ in }) {
+ init(value: Binding<Double?>,
+ isResponder: Binding<Bool>?,
+ alwaysShowFractions: Bool,
+ numberOfDecimalPlaces: Int,
+ onReturn: @escaping () -> Void = {},
+ onEditingChanged: @escaping (Bool) -> Void = { _ in }
+ ) {
  print("coordinator init")
  _value = value
  internalValue = value.wrappedValue
  self.isResponder = isResponder
  self.alwaysShowFractions = alwaysShowFractions
+ self.numberOfDecimalPlaces = numberOfDecimalPlaces
  self.onReturn = onReturn
  self.onEditingChanged = onEditingChanged
  }
@@ -226,7 +236,7 @@ public struct CurrencyTextField: UIViewRepresentable {
  let originalText = textField.text
  let text = textField.text as NSString?
  let newValue = text?.replacingCharacters(in: range, with: string)
- let display = newValue?.currencyFormat
+ let display = newValue?.currencyFormat(decimalPlaces: self.numberOfDecimalPlaces)
 
  // validate change
  if !shouldAllowChange(oldValue: textField.text ?? "", newValue: newValue ?? "") {
@@ -293,7 +303,7 @@ public struct CurrencyTextField: UIViewRepresentable {
  }
 
  // limits fractions length
- if newValue.fractions?.count ?? 0 > 2 {
+ if newValue.fractions?.count ?? 0 > self.numberOfDecimalPlaces {
  return false
  }
 
@@ -307,7 +317,7 @@ public struct CurrencyTextField: UIViewRepresentable {
  }
 
  public func textFieldDidEndEditing(_ textField: UITextField) {
- textField.text = self.value?.currencyFormat(decimalPlaces: self.alwaysShowFractions ? 2 : nil)
+ textField.text = self.value?.currencyFormat(decimalPlaces: self.numberOfDecimalPlaces, forceShowDecimalPlaces: self.alwaysShowFractions)
  DispatchQueue.main.async {
  self.isResponder?.wrappedValue = false
  }
@@ -370,25 +380,24 @@ fileprivate extension String {
  return Double(decimals) ?? 0
  }
 
- var currencyFormat: String? {
+ // args:
+ // decimalPlaces - the max number of decimal places
+ func currencyFormat(decimalPlaces: Int? = nil) -> String? {
  // uses self.double
  // logic for varying the number of fraction digits
- 
  guard let double = double else {
  return nil
  }
 
  let formatter = Formatter.currency
- let fractionDigits = fractions?.count ?? 0
+ 
  // if has fractions, show fractions
  if fractions != nil {
- if fractionDigits == 0 {
- formatter.maximumFractionDigits = 0
- } else if fractionDigits == 1 {
- formatter.maximumFractionDigits = 1
- } else {
- formatter.maximumFractionDigits = 2
- }
+ // the number of decimal points in the string
+ let fractionDigits = fractions?.count ?? 0
+ // limited to the decimalPlaces specified in the argument
+ formatter.minimumFractionDigits = min(fractionDigits, decimalPlaces != nil ? decimalPlaces! : 2)
+ formatter.maximumFractionDigits = min(fractionDigits, decimalPlaces != nil ? decimalPlaces! : 2)
 
  let formatted = formatter.string(from: NSNumber(value: double))
 
@@ -397,33 +406,37 @@ fileprivate extension String {
  return "\(formatted)."
  }
 
- return formatted
- } else {
- formatter.maximumFractionDigits = 0
- let formatted = formatter.string(from: NSNumber(value: double))
  return formatted
  }
+ 
+ formatter.maximumFractionDigits = 0
+ let formatted = formatter.string(from: NSNumber(value: double))
+ return formatted
  }
 }
 
 fileprivate extension Double {
- func currencyFormat(decimalPlaces: Int? = nil) -> String? {
+ // args:
+ // decimalPlaces - number of decimal places
+ // forceShowDecimalPlaces - whether to force show fractions
+ func currencyFormat(decimalPlaces: Int? = nil, forceShowDecimalPlaces: Bool = false) -> String? {
  let formatter = Formatter.currency
  var integer = 0.0
- 
- // if decimal places specified
- if let decimalPlaces = decimalPlaces {
- formatter.maximumFractionDigits = 2
+ let d = decimalPlaces != nil ? decimalPlaces! : 2
+
+ if forceShowDecimalPlaces {
+ formatter.minimumFractionDigits = d
+ formatter.maximumFractionDigits = d
  } else {
- // format to 2 decimal places if there's fractions
+ // show fractions if exist
  let fraction = modf(self, &integer)
  if fraction > 0 {
- formatter.maximumFractionDigits = 2
+ formatter.maximumFractionDigits = d
  } else {
  formatter.maximumFractionDigits = 0
  }
  }
- 
+
  return formatter.string(from: NSNumber(value: self))
  }
 }