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<!DOCTYPE html> | |
<html> | |
<head> | |
<meta name="viewport" content="initial-scale=1.0" /> | |
</head> | |
<body> | |
<div id="editor" contenteditable="true"></div> | |
</body> | |
</html> |
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var richeditor = {}; | |
var editor = document.getElementById("editor"); | |
richeditor.insertText = function(text) { | |
editor.innerHTML = text; | |
window.webkit.messageHandlers.heightDidChange.postMessage(document.body.offsetHeight); | |
} | |
editor.addEventListener("input", function() { | |
window.webkit.messageHandlers.textDidChange.postMessage(editor.innerHTML); | |
}, false) | |
document.addEventListener("selectionchange", function() { | |
window.webkit.messageHandlers.heightDidChange.postMessage(document.body.offsetHeight); | |
}, false); |
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public protocol RichTextEditorDelegate: class { | |
func textDidChange(text: String) | |
func heightDidChange() | |
} | |
fileprivate class WeakScriptMessageHandler: NSObject, WKScriptMessageHandler { | |
weak var delegate: WKScriptMessageHandler? | |
init(delegate: WKScriptMessageHandler) { | |
self.delegate = delegate | |
} | |
public func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) { | |
self.delegate?.userContentController(userContentController, didReceive: message) | |
} | |
} | |
public class RichTextEditor: UIView, WKScriptMessageHandler, WKNavigationDelegate, UIScrollViewDelegate { | |
private static let textDidChange = "textDidChange" | |
private static let heightDidChange = "heightDidChange" | |
private static let defaultHeight: CGFloat = 60 | |
public weak var delegate: RichTextEditorDelegate? | |
public var height: CGFloat = RichTextEditor.defaultHeight | |
public var placeholder: String? { | |
didSet { | |
placeholderLabel.text = placeholder | |
} | |
} | |
private var textToLoad: String? | |
public var text: String? { | |
didSet { | |
guard let text = text else { return } | |
if editorView.isLoading { | |
textToLoad = text | |
} else { | |
editorView.evaluateJavaScript("richeditor.insertText(\"\(text.htmlEscapeQuotes)\");", completionHandler: nil) | |
placeholderLabel.isHidden = !text.htmlToPlainText.isEmpty | |
} | |
} | |
} | |
private var editorView: WKWebView! | |
private let placeholderLabel = UILabel() | |
public override init(frame: CGRect = .zero) { | |
placeholderLabel.textColor = UIColor.lightGray.withAlphaComponent(0.65) | |
guard let bundlePath = Bundle(for: type(of: self)).path(forResource: "Resources", ofType: "bundle"), | |
let bundle = Bundle(path: bundlePath), | |
let scriptPath = bundle.path(forResource: "RichTextEditor", ofType: "js"), | |
let scriptContent = try? String(contentsOfFile: scriptPath, encoding: String.Encoding.utf8), | |
let htmlPath = bundle.path(forResource: "RichTextEditor", ofType: "html"), | |
let html = try? String(contentsOfFile: htmlPath, encoding: String.Encoding.utf8) | |
else { fatalError("Unable to find javscript/html for text editor") } | |
let configuration = WKWebViewConfiguration() | |
configuration.userContentController.addUserScript( | |
WKUserScript(source: scriptContent, | |
injectionTime: .atDocumentEnd, | |
forMainFrameOnly: true | |
) | |
) | |
editorView = WKWebView(frame: .zero, configuration: configuration) | |
super.init(frame: frame) | |
[RichTextEditor.textDidChange, RichTextEditor.heightDidChange].forEach { | |
configuration.userContentController.add(WeakScriptMessageHandler(delegate: self), name: $0) | |
} | |
editorView.navigationDelegate = self | |
editorView.isOpaque = false | |
editorView.backgroundColor = .clear | |
editorView.scrollView.isScrollEnabled = false | |
editorView.scrollView.showsHorizontalScrollIndicator = false | |
editorView.scrollView.showsVerticalScrollIndicator = false | |
editorView.scrollView.bounces = false | |
editorView.scrollView.isScrollEnabled = false | |
editorView.scrollView.delegate = self | |
addSubview(placeholderLabel) | |
placeholderLabel.translatesAutoresizingMaskIntoConstraints = false | |
NSLayoutConstraint.activate([ | |
placeholderLabel.leadingAnchor.constraint(equalTo: leadingAnchor, constant: 16), | |
placeholderLabel.topAnchor.constraint(equalTo: topAnchor), | |
placeholderLabel.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -16), | |
placeholderLabel.bottomAnchor.constraint(equalTo: bottomAnchor) | |
]) | |
addSubview(editorView) | |
editorView.translatesAutoresizingMaskIntoConstraints = false | |
NSLayoutConstraint.activate([ | |
editorView.leadingAnchor.constraint(equalTo: leadingAnchor, constant: 8), | |
editorView.topAnchor.constraint(equalTo: topAnchor, constant: 10), | |
editorView.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -8), | |
editorView.bottomAnchor.constraint(equalTo: bottomAnchor) | |
]) | |
editorView.loadHTMLString(html, baseURL: nil) | |
} | |
public required init?(coder aDecoder: NSCoder) { | |
super.init(coder: aDecoder) | |
} | |
public func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) { | |
switch message.name { | |
case RichTextEditor.textDidChange: | |
guard let body = message.body as? String else { return } | |
placeholderLabel.isHidden = !body.htmlToPlainText.isEmpty | |
delegate?.textDidChange(text: body) | |
case RichTextEditor.heightDidChange: | |
guard let height = message.body as? CGFloat else { return } | |
self.height = height > RichTextEditor.defaultHeight ? height + 30 : RichTextEditor.defaultHeight | |
delegate?.heightDidChange() | |
default: | |
break | |
} | |
} | |
public func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) { | |
if let textToLoad = textToLoad { | |
self.textToLoad = nil | |
text = textToLoad | |
} | |
} | |
public func viewForZooming(in: UIScrollView) -> UIView? { | |
return nil | |
} | |
} | |
fileprivate extension String { | |
var htmlToPlainText: String { | |
return [ | |
("(<[^>]*>)|(&\\w+;)", " "), | |
("[ ]+", " ") | |
].reduce(self) { | |
try! $0.replacing(pattern: $1.0, with: $1.1) | |
}.resolvedHTMLEntities | |
} | |
var resolvedHTMLEntities: String { | |
return self | |
.replacingOccurrences(of: "'", with: "'") | |
.replacingOccurrences(of: "'", with: "'") | |
.replacingOccurrences(of: "&", with: "&") | |
.replacingOccurrences(of: " ", with: " ") | |
} | |
func replacing(pattern: String, with template: String) throws -> String { | |
let regex = try NSRegularExpression(pattern: pattern, options: .caseInsensitive) | |
return regex.stringByReplacingMatches(in: self, options: [], range: NSRange(0..<self.utf16.count), withTemplate: template) | |
} | |
var htmlEscapeQuotes: String { | |
return [ | |
("\"", "\\\""), | |
("“", """), | |
("\r", "\\r"), | |
("\n", "\\n") | |
].reduce(self) { | |
return $0.replacingOccurrences(of: $1.0, with: $1.1) | |
} | |
} | |
} |
Is there any way to reproduce it on SwiftUI?
I didn't test it but UIViewRepresentable
could be your friend here.
@sonnguyen9800 Yes, I have used it in my SwiftUI project:
struct RichTextEditorView: UIViewRepresentable {
@Binding var htmlText: String
@Binding var dynamicHeight: CGFloat
class Coordinator: NSObject, RichTextEditorDelegate {
var parent: RichTextEditorView
init(_ parent: RichTextEditorView) {
self.parent = parent
}
func textDidChange(text: String) {
parent.htmlText = text
}
func heightDidChange(newHeight: CGFloat) {
parent.dynamicHeight = newHeight
}
}
func makeCoordinator() -> Coordinator {
return Coordinator(self)
}
func makeUIView(context: Context) -> RichEditorWebView {
let editor = RichEditorWebView()
editor.delegate = context.coordinator
editor.text = htmlText
return editor
}
func updateUIView(_ editor: RichEditorWebView, context: Context) {}
}
Great gist! Any suggestions for a JavaScript library that can apply formatting to the selected text (like toggling bold, etc)?
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Is there any way to reproduce it on SwiftUI?