JavaFX WebView - 如何捕获 URL 加载？

Question

我目前正在使用 GluonHQ (JavaFXPorts) 开发一个应用程序，我正在使用 WebView 加载一些 Internet 页面。当我加载 https://signin.ebay.com/ 页面时，我在控制台上看到以下消息

[WebEngine] I can handle this protocol for https://signin.ebay.com/
ES2ResourceFactory: Prism - createStockShader: AlphaTexture_RadialGradient.frag
[WebEngine] I can handle this protocol for https://www.ebay.com/ws/
[WebEngine] I can't handle this protocol for about:blank
[WebEngine] I can handle this protocol for https://www.ebay.com/t_n.html?org_id=usllpic0&session_id=f5b8d48d1670a9cce3431193fffe9431&suppressFlash=true
[WebEngine] I can't handle this protocol for about:blank
2018-12-28 18:49:53 Watchdog[2021:302159] WF: _userSettingsForUser mobile: {
    filterBlacklist =     (
    );
    filterWhitelist =     (
    );
    restrictWeb = 1;
    useContentFilter = 0;
    useContentFilterOverrides = 0;
    whitelistEnabled = 0;
}
2018-12-28 18:49:53 Watchdog[2021:302159] WF: _WebFilterIsActive returning: NO
2018-12-28 18:49:55 Watchdog[2021:302159] CoreAnimation: [EAGLContext renderbufferStorage:fromDrawable:] was called from a non-main thread in an implicit transaction! Note that this may be unsafe without an explicit CATransaction or a call to [CATransaction flush].
[WebEngine] I can handle this protocol for https://src.ebay-us.com/fp/top_fp.html;CIS3SID=08561C52B9A266EE68861D27BCE99A74?org_id=usllpic0&session_id=f5b8d48d1670a9cce3431193fffe9431&nonce=b6190f233a143165

似乎该应用程序也调用了其他站点的负载，但我找不到捕获它们的方法。我也尝试在状态更改时获取位置

webEngine.getLoadWorker().stateProperty().addListener((ov, oldState, newState) -> {
    System.out.println("State(" + newState + "): " + webEngine.getLocation());
}

但没有任何成功。在第一次加载站点之前，该位置似乎为空，然后返回原始 URL，即https://signin.ebay.com。我相信出现的额外“协议”是 AJAX 的一部分。任何人都知道如何实现监听器来捕获这些？

[WebEngine] I can handle this protocol for https://signin.ebay.com/
State(SCHEDULED): null
State(RUNNING):   null
ES2ResourceFactory: Prism - createStockShader: AlphaTexture_RadialGradient.frag
[WebEngine] I can handle this protocol for https://www.ebay.com/ws/
[WebEngine] I can't handle this protocol for about:blank
State(SCHEDULED): null
State(RUNNING):   null
State(SUCCEEDED): null
[WebEngine] I can handle this protocol for https://www.ebay.com/t_n.html?org_id=usllpic0&session_id=f5c7ab7f1670a9ccaac210b2ffe8709e&suppressFlash=true
State(SCHEDULED): https://signin.ebay.com
State(RUNNING):   https://signin.ebay.com
[WebEngine] I can't handle this protocol for about:blank
State(SCHEDULED): https://signin.ebay.com
State(RUNNING):   https://signin.ebay.com
State(SUCCEEDED): https://signin.ebay.com
2018-12-28 19:06:05 Watchdog[2050:306357] WF: _userSettingsForUser mobile: {
    filterBlacklist =     (
    );
    filterWhitelist =     (
    );
    restrictWeb = 1;
    useContentFilter = 0;
        useContentFilterOverrides = 0;
        whitelistEnabled = 0;
    }
2018-12-28 19:06:05 Watchdog[2050:306357] WF: _WebFilterIsActive returning: NO
2018-12-28 19:06:09 Watchdog[2050:306357] CoreAnimation: [EAGLContext renderbufferStorage:fromDrawable:] was called from a non-main thread in an implicit transaction! Note that this may be unsafe without an explicit CATransaction or a call to [CATransaction flush].
[WebEngine] I can handle this protocol for https://src.ebay-us.com/fp/top_fp.html;CIS3SID=D553152B77DCBE35641E606BDAB6AFDA?org_id=usllpic0&session_id=f5c7ab7f1670a9ccaac210b2ffe8709e&nonce=f3e7bb25c25eb5c1
State(SCHEDULED): https://signin.ebay.com
State(RUNNING):   https://signin.ebay.com
State(SUCCEEDED): https://signin.ebay.com

Answer 1

作为类似question 的后续行动，其中声明：

使用 JavaFXPorts，在移动设备（Android 和 iOS）上，WebView 控件不是 JavaFX 内置控件，而是本机控件

在原生implementation中可以看到这个方法：

- (BOOL)webView:(UIWebView *)wv shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType {
    NSString *url = [[request URL] absoluteString];
    JNIEnv *env = [self getJNIEnv];
    if (env != NULL) {
        jstring jUrl = createJString(env, url);
        (*env)->CallVoidMethod(env, jObject, jmidHasAppProtocolHandler, jUrl);
    ...
}

进入 JavaFX WebEngine callback:

/**
 * check if there is a handler registered for dealing with this protocol.
 */
boolean hasAppProtocolHandler(String url) {
    boolean answer = false;
    try {
        URL u = newURL(null, url);
        System.out.println ("[WebEngine] I can handle this protocol for "+url);
        u.openConnection();
        // location.set(url);
        answer = true;
    }
    // catch (MalformedURLException e) {
    catch (Exception e) {
        System.out.println ("[WebEngine] I can't handle this protocol for "+url);
        // no handler known for this protocol
    }
    return answer;
}

这解释了控制台打印输出：何时可以打开 URL，或者何时出现异常。所有不同的结果似乎都与本机浏览器处理 URL 加载的方式有关，但您只会在 JavaFX 层中得到回声。

关于使用WebEngine::getLocation，注意只有当原生浏览器加载完一个Url后，才会发回通知，location is set：

void notifyLoadFinished(String loc, String content) {
    synchronized (loadedLock) {
        this.pageContent = "<html>"+content+"</html>";
        loaded = true;
        updateProgress(1.0);
        updateState(Worker.State.SUCCEEDED);
        location.set(loc); // <--- location from native browser is set
        document.invalidate(true);
        if (pageListener != null) {
            pageListener.onLoadFinished();
        }
    }
}

我建议您查看适用于 iOS 平台的 WebView 和 WebEngine 的 JavaFX 代码，了解哪些可以做，哪些不能做。

例如，脚本引擎可以工作，所以你可以execute 一些脚本，它会报告一些信息。