iOS Swift-WKWebView

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涵盖的知识点:

获取webView 加载url 链接中的参数
WKWebView 在Swift 中的使用
WKWebView 的navigationDelegate方法含义
去掉WKWebView 键盘自带的工具栏

1. 获取webView 加载url 链接中的参数

       // 通过URL 的query 参数获得所有的参数的一个字符串
        let url = URL(string: "http://www.example.com/response?code=1234")
        guard let u = url else {
            return
        }
        
        let query = u.query
        guard let q = query else {
            return
        }
        print(q) // code=1234
        // 以字符串截取的形式 来获取想要的参数
        let code = String(q["code=".endIndex...])
        print(code) // 1234

2. WKWebView 在Swift 中的使用

Swift 5.0之后 使用WKWebView 需要引入头文件import WebKit, 且UIWebView 在4月份就被彻底废弃了.

3. WKWebView 的navigationDelegate方法含义

    // 页面开始加载时调用
    func webView(_ webView: WKWebView, didStartProvisionalNavigation navigation: WKNavigation!) {
        
    }
    // 当内容开始返回时调用
    func webView(_ webView: WKWebView, didCommit navigation: WKNavigation!) {
        
    }
    // 页面加载完成之后调用
    func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
        
    }
    // 页面加载失败时调用
    func webView(_ webView: WKWebView, didFailProvisionalNavigation navigation: WKNavigation!, withError error: Error) {
        
    }
    // 接收到服务器跳转请求之后调用
    func webView(_ webView: WKWebView, didReceiveServerRedirectForProvisionalNavigation navigation: WKNavigation!) {
        
    }
    // 在收到响应后，决定是否跳转 -> 默认允许
    func webView(_ webView: WKWebView, decidePolicyFor navigationResponse: WKNavigationResponse, decisionHandler: @escaping (WKNavigationResponsePolicy) -> Void) {
        //允许跳转
        decisionHandler(.allow)
        //不允许跳转
//        decisionHandler(.cancel)
    }
    // 在发送请求之前，决定是否跳转 -> 默认允许
    func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, preferences: WKWebpagePreferences, decisionHandler: @escaping (WKNavigationActionPolicy, WKWebpagePreferences) -> Void) {
        decisionHandler(.allow, preferences)
    }

4. 去掉WKWebView 键盘自带的工具栏

需要去掉工具栏的WKWebView 直接调用hack_removeInputAccessory即可.

// MARK: 去掉WKWebView自带的 工具栏
fileprivate final class InputAccessoryHackHelper: NSObject {
    @objc var inputAccessoryView: AnyObject? { return nil }
}

extension WKWebView {
    func hack_removeInputAccessory() {
        guard let target = scrollView.subviews.first(where: {
            String(describing: type(of: $0)).hasPrefix("WKContent")
        }), let superclass = target.superclass else {
            return
        }
        
        let noInputAccessoryViewClassName = "\(superclass)_NoInputAccessoryView"
        var newClass: AnyClass? = NSClassFromString(noInputAccessoryViewClassName)
        
        if newClass == nil, let targetClass = object_getClass(target), let classNameCString = noInputAccessoryViewClassName.cString(using: .ascii) {
            newClass = objc_allocateClassPair(targetClass, classNameCString, 0)
            
            if let newClass = newClass {
                objc_registerClassPair(newClass)
            }
        }
        
        guard let noInputAccessoryClass = newClass, let originalMethod = class_getInstanceMethod(InputAccessoryHackHelper.self, #selector(getter: InputAccessoryHackHelper.inputAccessoryView)) else {
            return
        }
        class_addMethod(noInputAccessoryClass.self, #selector(getter: InputAccessoryHackHelper.inputAccessoryView), method_getImplementation(originalMethod), method_getTypeEncoding(originalMethod))
        object_setClass(target, noInputAccessoryClass)
    }
}