【发布时间】：2019-01-23 02:28:52
【问题描述】：
我正在尝试直接在 WKWebView 中加载 PDF，而不向 URL 发出另一个直接请求。
在我的研究过程中，我遇到了下面的链接，它做同样的事情。 IOS - How to get cached resources from WKWebView?
但在这种方法中，我在某些 URL 中遇到了问题。
我在控制台中收到 Javascript 错误
Blocked script execution in 'https://ac.els-cdn.com/S0946672X17308763/1-s2.0-S0946672X17308763-main.pdf?_tid=8d087878-4e4c-4c50-b5e4-08ea38906e6e&download=true&acdnat=1534405212_984aaf5f9673f1b2ff107a4032c80ea0' because the document's frame is sandboxed and the 'allow-scripts' permission is not set.
重现问题的 URL。 https://www.sciencedirect.com/science/article/pii/S0946672X17308763 只需访问下载 PDF 链接并在 WKWebView 中打开 PDF。
为便于在同一个 WebView 中加载新的选项卡窗口而进行编辑。
-(WKWebView *)webView:(WKWebView *)webView createWebViewWithConfiguration:(WKWebViewConfiguration *)configuration forNavigationAction:(WKNavigationAction *)navigationAction windowFeatures:(WKWindowFeatures *)windowFeatures{
if (!navigationAction.targetFrame.isMainFrame) {
[_webView loadRequest:navigationAction.request];
}
return nil;
}
编辑
我正在添加从@SahilManchanda 提供的解决方案派生的完整 swift 代码，但在代码 sn-p 中添加的链接仍然存在一些问题。
import UIKit
import WebKit
class ViewController: UIViewController {
var webView: WKWebView!
var button: UIButton!
let link = "https://www.sciencedirect.com/science/article/pii/S0946672X17308763"
var activityIndicator: UIActivityIndicatorView?
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
webView = WKWebView()
button = UIButton()
button.setTitle("Save", for: .normal)
button.setTitleColor(.white, for: .normal)
button.backgroundColor = UIColor.black.withAlphaComponent(0.5)
button.addTarget(self, action: #selector(self.download(_:)), for: .touchUpInside)
activityIndicator = UIActivityIndicatorView(activityIndicatorStyle: .gray)
webView.navigationDelegate = self
webView.uiDelegate = self
activityIndicator?.center = self.view.center
[webView,button].forEach({view.addSubview($0)})
setupConstraints()
webView.configuration.userContentController.add(self, name: "myInterface")
webView.load(URLRequest(url: URL(string: link)!))
activityIndicator?.startAnimating()
}
func setupConstraints(){
webView.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
webView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
webView.topAnchor.constraint(equalTo: view.topAnchor),
webView.trailingAnchor.constraint(equalTo: view.trailingAnchor),
webView.bottomAnchor.constraint(equalTo: view.bottomAnchor)
])
button.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
button.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: -70),
button.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -20),
button.widthAnchor.constraint(equalToConstant: 100)
])
}
@objc func download(_ sender: Any){
let s = """
var xhr = new XMLHttpRequest();
xhr.open('GET', "\(webView.url!.absoluteString)", true);
xhr.responseType = 'arraybuffer';
xhr.onload = function(e) {
if (this.status == 200) {
var uInt8Array = new Uint8Array(this.response);
var i = uInt8Array.length;
var binaryString = new Array(i);
while (i--){
binaryString[i] = String.fromCharCode(uInt8Array[i]);
}
var data = binaryString.join('');
var base64 = window.btoa(data);
window.webkit.messageHandlers.myInterface.postMessage(base64);
}
};
xhr.send();
"""
webView?.evaluateJavaScript(s, completionHandler: {(string,error) in
print(error ?? "no error")
})
}
}
extension ViewController: WKScriptMessageHandler{
func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
guard
var documentsURL = (FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)).last,
let convertedData = Data.init(base64Encoded: message.body as! String)
else {
//handle error when getting documents URL
return
}
//name your file however you prefer
documentsURL.appendPathComponent("sample.pdf")
do {
try convertedData.write(to: documentsURL)
} catch {
//handle write error here
}
//if you want to get a quick output of where your
//file was saved from the simulator on your machine
//just print the documentsURL and go there in Finder
print("URL for view \(documentsURL.absoluteString)")
let activityViewController = UIActivityViewController.init(activityItems: [documentsURL], applicationActivities: nil)
present(activityViewController, animated: true, completion: nil)
}
}
extension ViewController: WKNavigationDelegate,WKUIDelegate{
func webView(_ webView: WKWebView, createWebViewWith configuration: WKWebViewConfiguration, for navigationAction: WKNavigationAction, windowFeatures: WKWindowFeatures) -> WKWebView? {
if !(navigationAction.targetFrame != nil && (navigationAction.targetFrame?.isMainFrame)!){
webView .load(navigationAction.request);
}
return nil
}
func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
self.activityIndicator?.stopAnimating()
self.activityIndicator?.removeFromSuperview()
self.activityIndicator = nil
}
}
【问题讨论】：
-
点击下载->然后出现弹出窗口->点击下载pdf。它没有在 wkwebview 中自动打开。但是我在 navigationAction 委托中获得了下载链接，例如sciencedirect.com/science/article/pii/S0946672X16303777/…你能指导我如何在webview中加载pdf吗？
-
根据 WKWebview 文档，如果它设置为 _blank，它通常不会直接打开链接目标，所以这里也发生了同样的事情。如果你想打开它，你必须在
-(WKWebView *)webView:(WKWebView *)webView createWebViewWithConfiguration:(WKWebViewConfiguration *)configuration forNavigationAction:(WKNavigationAction *)navigationAction windowFeatures:(WKWindowFeatures *)windowFeatures中提出另一个请求 -
或者只使用来自 ScienceDirect 网站的任何直接 PDF URL。它发生在所有有一些标头作为服务器响应的地方。例如sciencedirect.com/science/article/pii/S0946672X17308763/…
-
已添加代码 sn-p 用于在同一位置加载 PDF。
-
给我一分钟。让我检查
标签： ios objective-c webview wkwebview