KPEnhancedEntryView: A Complete Developer’s Guide
Overview
KPEnhancedEntryView is a custom input component (assumed for iOS/tvOS/macOS) that extends a standard text entry with additional features like validation, formatting, placeholder animations, and accessibility improvements. This guide covers installation, API surface, implementation patterns, customization, performance considerations, testing, and accessibility.
Installation
- CocoaPods
ruby
pod ‘KPEnhancedEntryView’
- Swift Package Manager
- In Xcode, choose File → Add Packages…
- Enter repository URL: https://github.com/yourorg/KPEnhancedEntryView
- Select the desired version.
Core Concepts & API
- KPEnhancedEntryView — main view class that wraps UITextField/UITextView.
- Properties
- text: String — current text.
- placeholder: String — placeholder text.
- style: EntryStyle — enum controlling floating label, underline, box, etc.
- keyboardType, autocapitalizationType, isSecureTextEntry — standard input props.
- validationRule: ((String) -> Bool)? — sync validator.
- asyncValidator: ((String, @escaping (Bool) -> Void) -> Void)? — async validation.
- formatter: ((String) -> String)? — transforms input for display (e.g., phone formatting).
- maxLength: Int?
- errorText: String?
- Events / Delegates
- onTextChanged: (String) -> Void
- onEditingBegan, onEditingEnded
- onValidationChanged: (ValidationState) -> Void where ValidationState = .unknown, .valid, .invalid
- Methods
- validate() -> Bool
- setError(🙂
- clear()
Usage Examples
Basic setup (programmatic)
swift
let entry = KPEnhancedEntryView() entry.placeholder = “Email” entry.keyboardType = .emailAddress entry.validationRule = { text in return NSPredicate(format:“SELF MATCHES %@”, ”[A-Z0-9a-z.%+-]+@[A-Za-z0-9.-]+.[A-Za-z]{2,}”).evaluate(with: text) } entry.onValidationChanged = { state in switch state { case .valid: entry.setError(nil) case .invalid: entry.setError(“Invalid email”) default: break } } view.addSubview(entry)
Using formatter and maxLength
swift
entry.formatter = { input in // simple phone grouping return input.filter { $0.isNumber } .chunked(into: 3).joined(separator: ”-”) } entry.maxLength = 12
Async validation (e.g., username availability)
swift
entry.asyncValidator = { text, completion in API.checkUsername(text) { available in completion(available) } }
Layout & Styling
- Style enum controls visual skins. Prefer Auto Layout constraints; the view exposes intrinsicContentSize.
- Provide theming via appearance proxies or a Theme struct:
- primaryColor, errorColor, placeholderColor, cornerRadius, font.
- For complex forms, compose KPEnhancedEntryView inside UIStackView for consistent spacing.
Accessibility
- Ensure accessibilityLabel includes placeholder and purpose.
- Announce validation changes with UIAccessibility.post(notification: .announcement, argument: “Email valid”)
- Support Dynamic Type by using scalable fonts and adjusting layout for larger sizes.
Performance Considerations
- Avoid heavy synchronous formatting on each keystroke; debounce or perform on background queue then apply on main.
- Reuse formatters.
- For async validation, cancel previous requests when new input arrives to avoid race conditions.
Testing
- Unit test validation and formatter functions with a variety of inputs.
- UI tests: verify placeholder animations, error state visuals, and keyboard behavior.
- Accessibility tests: verify VoiceOver reads placeholder, typed text, and validation announcements.
Common Pitfalls & Troubleshooting
- Placeholder overlap: ensure animations run on main thread and layoutIfNeeded() after state changes.
- Cursor jumping when applying formatter: preserve selectedTextRange or compute new position after formatting.
- Slow UI with complex regex: move to background thread and throttle validation.
Extending KPEnhancedEntryView
- Add new EntryStyle cases for material design or platform-specific styles.
- Provide delegate hooks for paste handling, input masking, or analytics.
- Implement compound fields (e.g., country code + phone number) by composing multiple instances.
Example: Full Form Integration
- Use a FormController that holds references to entries, subscribes to onValidationChanged, and enables submit only when all entries are valid.
- Debounce validation updates to avoid rapid UI churn.
Appendix: Helper Snippets
- Preserve cursor after formatting:
swift
func applyFormatted(_ newText: String, to textField: UITextField) { let oldOffset = textField.offset(from: textField.beginningOfDocument, to: textField.selectedTextRange!.start) textField.text = newText if let newPosition = textField.position(from: textField.beginningOfDocument, offset: min(oldOffset, newText.count)) { textField.selectedTextRange = textField.textRange(from: newPosition, to: newPosition) } }
Summary
KPEnhancedEntryView centralizes common input features (validation, formatting, accessibility) into a single reusable component. Use validation hooks, formatting, and accessibility announcements to create robust forms, and follow performance best practices (debounce, background work) to keep input smooth.
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