我正在使用MacOS应用程序，该应用程序需要使用WKUserScript功能将消息从网页发送回MacOS应用程序。我正在使用文章https://medium.com/capital-one-tech/javascript-manipulation-on-ios-using-webkit-2b1115e7e405，它显示了这在iOS中工作并且工作得很好。
然而，我已经挣扎了好几个星期，试图让它在我的MacOS中运行。这是我的代码的例子，它符合罚款并运行，但没有成功打印在处理程序userContentController（）中找到的消息
import Cocoa
import WebKit
class ViewController: NSViewController, WKNavigationDelegate {
@IBOutlet weak var webView: WKWebView!
override func viewDidLoad() {
super.viewDidLoad()
let userContentController = WKUserContentController()
// Add script message handlers that, when run, will make the function
// window.webkit.messageHandlers.test.postMessage() available in all frames.
userContentController.add(self, name: "test")
// Inject JavaScript into the webpage. You can specify when your script will be injected and for
// which frames–all frames or the main frame only.
let scriptSource = "window.webkit.messageHandlers.test.postMessage(`Hello, world!`);"
let userScript = WKUserScript(source: scriptSource, injectionTime: .atDocumentEnd, forMainFrameOnly: true)
userContentController.addUserScript(userScript)
// let config = WKWebViewConfiguration()
// config.userContentController = userContentController
// let webView = WKWebView(frame: .zero, configuration: config)
webView.navigationDelegate = self
webView.configuration.userContentController = userContentController
// Make sure in Info.plist you set `NSAllowsArbitraryLoads` to `YES` to load
// URLs with an HTTP connection. You can run a local server easily with services
// such as MAMP.
let htmlStr = "<html><body>Hello world - nojs</body></html>"
webView.loadHTMLString(htmlStr, baseURL: nil)
}
}
extension ViewController: WKScriptMessageHandler {
// Capture postMessage() calls inside loaded JavaScript from the webpage. Note that a Boolean
// will be parsed as a 0 for false and 1 for true in the message's body. See WebKit documentation:
// https://developer.apple.com/documentation/webkit/wkscriptmessage/1417901-body.
func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
if let messageBody = message.body as? String {
print(messageBody)
}
}
}
另一件奇怪的事情是我似乎无法创建一个加载页面并显示它的简单WKWebView应用程序。这些都只是简单的测试，我的主要应用程序能够使用AlamoFire / loadHTMLString（）显示页面来加载/显示网页，我只是无法注入所需的JS。
我在转换中所做的一切都非常简单，除了userContentController的分配外，几乎不需要改变 - 所以也许这就是问题所在？这个例子在iOS中运行得很好，原始样本作为原型。 https://github.com/rckim77/WKWebViewDemoApp/blob/master/WKWebViewDemoApp/ViewController.swift
我猜我必须有一些非常简单的东西。任何帮助将不胜感激！
以下是我如何在Mac上设置我的WebView尝试这样的事情
import Cocoa
import WebKit
class ViewController: NSViewController {
@IBOutlet weak var webView: WKWebView!
override func viewDidLoad() {
super.viewDidLoad()
let javascript = """
function printStatement() {
try {
window.webkit.messageHandlers
.callbackHandler.postMessage({'payload': 'Hello World!'})
} catch(err) {
console.log('The native context does yet exist')
}
}
"""
let script = WKUserScript(
source: javascript,
injectionTime: WKUserScriptInjectionTime.atDocumentEnd,
forMainFrameOnly: true
)
webView.configuration.userContentController.add(
name: "callbackHandler"
)
webView.configuration.userContentController
.addUserScript(script)
webView.navigationDelegate = self
let html = """
<div onClick='javascript:printStatement()'>Print Statement</div>
"""
webView.loadHTMLString(html, nil)
}
}
extension ViewController: WKScriptMessageHandler {
func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
if(message.name == "callbackHandler") {
guard let body = message.body as? [String: Any] else {
print("could not convert message body to dictionary: \(message.body)")
return
}
guard let payload = body["payload"] as? String else {
print("Could not locate payload param in callback request")
return
}
print(payload)
}
}
}
希望这回答了你的问题，如果不让我知道，我会尝试解决它！
好吧，事实证明，问题的一个主要部分是我需要将“App Sandbox”和“com.apple.security.files.user-selected.read-only”的权利设置为“no”in WebTest.entitlements文件。
在以前版本的XCode中我不是这种情况（我在V10.1上），默认值基本上禁用了WKWebView，因为我试图用它做什么（即通过URL或String加载一个简单的页面）
然而，一旦我解决了这个问题，Alex的修复确实有所帮助......只需要一些小的调整（必须在userContentController.add（）函数中添加'self'。另外，我添加了我的JS，因为它的原始目的是“推” “每次用户更改页面上的选择时都要使用Swift。
这是我的最终代码：
import Cocoa
import WebKit
class ViewController: NSViewController, WKNavigationDelegate {
@IBOutlet var webView: WKWebView!
override func viewDidLoad() {
super.viewDidLoad()
let javascript = """
function printStatement() {
try {
var foo = window.getSelection().toString()
window.webkit.messageHandlers.callbackHandler.postMessage({'payload': foo})
} catch(err) {
console.log('The native context does yet exist')
}
}
function getSelectionAndSendMessage() {
try {
var currSelection = window.getSelection().toString()
window.webkit.messageHandlers.callbackHandler.postMessage({'payload': currSelection})
} catch(err) {
console.log('The native context does yet exist')
}
}
document.onmouseup = getSelectionAndSendMessage;
document.onkeyup = getSelectionAndSendMessage;
document.oncontextmenu = getSelectionAndSendMessage;
"""
let script = WKUserScript(
source: javascript,
injectionTime: WKUserScriptInjectionTime.atDocumentEnd,
forMainFrameOnly: true
)
webView.configuration.userContentController.add(self, name: "callbackHandler")
webView.configuration.userContentController.addUserScript(script)
webView.navigationDelegate = self
let html = """
<div onClick='javascript:printStatement()'>Print Statement</div>
This is some sample text to test select with
"""
webView.loadHTMLString(html, baseURL: nil)
}
}
extension ViewController: WKScriptMessageHandler {
func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
if(message.name == "callbackHandler") {
guard let body = message.body as? [String: Any] else {
print("could not convert message body to dictionary: \(message.body)")
return
}
guard let payload = body["payload"] as? String else {
print("Could not locate payload param in callback request")
return
}
print(payload)
}
}
}
感谢Alex为您提供的所有支持！