webkit-browser

WebKit & Browser Development Guidelines

WebView Configuration

Basic WebView Setup

import WebKit

class BrowserWebView {
    private lazy var webView: WKWebView = {
        let configuration = WKWebViewConfiguration()
        
        // Enable JavaScript
        configuration.preferences.javaScriptEnabled = true
        
        // Set user agent
        configuration.applicationNameForUserAgent = UserAgentManager.shared.userAgent
        
        // Configure content blockers
        configuration.userContentController = makeUserContentController()
        
        // Enable developer extras in debug
        #if DEBUG
        configuration.preferences.setValue(true, forKey: "developerExtrasEnabled")
        #endif
        
        let webView = WKWebView(frame: .zero, configuration: configuration)
        webView.allowsBackForwardNavigationGestures = true
        webView.allowsLinkPreview = true
        
        return webView
    }()
}

User Scripts Management

private func makeUserContentController() -> WKUserContentController {
    let controller = WKUserContentController()
    
    // Add content blocking scripts
    let contentBlockingScript = WKUserScript(
        source: ContentBlockingUserScript.source,
        injectionTime: .atDocumentStart,
        forMainFrameOnly: false
    )
    controller.addUserScript(contentBlockingScript)
    
    // Add message handlers
    controller.add(self, name: "duckduckgo")
    
    return controller
}

Tab Management

Tab Model

class Tab: NSObject {
    let id = UUID()
    private(set) var url: URL?
    private(set) var title: String?
    private(set) var favicon: UIImage?
    
    weak var webView: WKWebView?
    weak var delegate: TabDelegate?
    
    private var observations: Set<NSKeyValueObservation> = []
    
    init(url: URL? = nil) {
        self.url = url
        super.init()
        setupWebView()
    }
    
    private func setupWebView() {
        let webView = WKWebView(frame: .zero, configuration: TabManager.shared.configuration)
        self.webView = webView
        
        // Observe properties
        observations.insert(
            webView.observe(\.url) { [weak self] _, _ in
                self?.urlDidChange()
            }
        )
        
        observations.insert(
            webView.observe(\.title) { [weak self] webView, _ in
                self?.title = webView.title
                self?.delegate?.tab(self!, didUpdateTitle: webView.title)
            }
        )
        
        observations.insert(
            webView.observe(\.estimatedProgress) { [weak self] webView, _ in
                self?.delegate?.tab(self!, didUpdateProgress: webView.estimatedProgress)
            }
        )
    }
}