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WebView does not recognize history state in some cases

In my Android app I implemented a common approach to "go back on back-button pressed":
private WebView webView; // my WebView
#Override
public void onBackPressed() {
if(webView.canGoBack()) webView.goBack();
else super.onBackPressed();
}
But today I noticed a weird thing. If, on the very first webpage loaded on webView, it calls history.pushState(...) automatically, then webView.canGoBack() will return false, causing the approach above to fail (even if I execute webView.goBack() directly, nothing happens in the webView), although executing history.back() still works within the webpage itself. I've also tried calling history.pushState automatically using setTimeout, with the same result. However, if history.pushState is called manually, i.e. triggered by some user events, then webView.canGoBack() is true and the code works.
It seems to me that this is a bug of WebViews. Any ideas?

C#: .NET based webbrowser doesn't show image

I am new in C# language and I have been trying to automate a website using .NET based webbrowser for ONLY personal use in Visual Studio 2015.
I have done document parsing, used Timer, used DocumentCompleted event properly to wait for the webpage to load completely and then parse the content, tried to make async events to behave like sync events (in order to load HTML content generated by clicking a link in a fully loaded webpage), etc to go through the phases in webpage automation: login -> get trains between stations -> click the Book now link -> go to the next page and fill in the passenger details.
Everything works fine but I am now stuck at the last phase, i.e., "go to the next page and fill in the passenger details" has a captcha image that must be resolved to go to the payment page. Don't get me wrong because I am not trying to get this captcha resolved automatically. The problem here is that I do not see the captch image which turned to be loaded only when this javascript call is invoked $(document).ready.
I thought my project has some buggy code which is stopping to load the captcha and therefore, I created a very basic new project, only added below code and navigated through different phases myself to see if the captcha really loads but unfortunately it would not load.
namespace TestWebBrowser
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
webBrowser1.Navigate("https://www.irctc.co.in/eticketing/loginHome.jsf");
}
private void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
}
}
}
Please see below. The highlighted part is where I am expecting a captcha.
I must tell you that I am not a web designer and therefore I only understand very basic of how websites work.
I went through several questions on this forum and nothing helped me.
Internet explorer is also using .NET browser from behind but while using IE, I can see the captcha is getting loaded. So, why is this javascript call $(document).ready is not getting invoked in .NET browser. Please see below:
I have later tried to use CefSharp in a fresh new project and I can see the captcha is getting loaded in its chromium based webbrowser. But I have done so much coding with .NET based webbrowser already and therefore I want to stick to the latter at this moment in order to get this resolved.
Is this happening because .NET webbrowser is using some very old IE version configurations?
Please help me to understand.
UPDATE 1: Adding the javascript
<script type="text/javascript">
$(document).ready(function(){
var isJsBlocked=0;
if (typeof(nlpLoadCaptchaAsync) == 'function'){
nlpLoadCaptchaAsync();
}else{
isJsBlocked=1;
}
setTimeout(function(){
var isNLPCaptcha = document.getElementById('nlpIdentifier');
if(isNLPCaptcha == null || isNLPCaptcha=='' ) {
var nlptrack = new Image();
nlptrack.src="http://irctclive.nlpcaptcha.in/temp_redirect_count/irctc_timeout.php?ref=f2c5d744485b0b4251461454db791111&isJsBlocked="+isJsBlocked+"&dynamicParameter="+Date.now();
nlpCaptchaTimeOut(true);
}
}, 5000 );
});
</script>

The answer shared here: Use latest version of Internet Explorer in the webbrowser control solved my issue.
I basically had to change the version of IE version used by my webbrowser control.
Thanks to Matthias herrmann

Debugging Android WebViews?

I'm trying to debug an Android app that makes heavy use of WebViews to display web pages from within the app.
The problem is simple - when I load the page, there's an anchor on one page that when clicked gives me a 404. The problem, it does this only when running the page from within the app's WebView. If I load the page in a desktop browser, or from within Chrome or from within the Android Browser on the mobile, I load the page just fine.
More confusingly, there's another anchor on the same page with the same basic architecture that's working just fine.
The URL for the anchor is being set via JQuery:
var url = ...;
$('#submitButton').attr('href', url);
When I load the page on a desktop browser, I can see the URL that the anchor points to, and it's correct. When I run the page within an app's WebView, I cannot see the URL that the anchor points to, so when it fails, I don't know why.
I'm currently running the website with VS2013 and IIS Express, with bindings and firewalls set so I can access it off my machine. I'm building the app in Android Studio 1.1.0, and am running the app within a GenyMotion emulator.
Is there any way I can examine the DOM of a web page loaded into a webview, so I can see exactly what URL we're trying to load? Or any way I can debug the javascript that is constructing that URL?

Is there any way I can examine the DOM of a web page loaded into a webview, >so I can see exactly what URL we're trying to load? Or any way I can debug >the javascript that is constructing that URL?
Yes, but maybe not with your current tools.
If you do however have an android device connected to your computer, you can actually easily debug the webviews with chrome on your computer.
See the following for more details :
https://developer.chrome.com/devtools/docs/remote-debugging

It is possible to configure a WebView so that console.log() messages show up in LogCat. You need to set a WebChromeClient on the WebView, then implement onConsoleMessage() in your client. From http://developer.android.com/guide/webapps/debugging.html:
WebView myWebView = (WebView) findViewById(R.id.webview);
myWebView.setWebChromeClient(new WebChromeClient() {
public void onConsoleMessage(String message, int lineNumber, String sourceID) {
Log.d("MyApplication", message + " -- From line "
+ lineNumber + " of "
+ sourceID);
}
});
That got me far enough to figure out what my problem was - the javascript that initialized the link depended upon LocalStorage, and LocalStorage and SessionStorage aren't enabled, in WebViews, by default. You need to enable it with a call to setDomStorageEnabled(). (You also need to enable javascript, but I'd already been doing that):
WebView myWebView = (WebView) findViewById(R.id.webview);
WebSettings settings = myWebView.getSettings();
settings.setJavaScriptEnabled(true);
settings.setDomStorageEnabled(true);

IE detects XSS when invoking a method in GWT class using window.opener

I have a GWT application that opens a second browser window. I would like my second window to be able to call a method within the entry point of the first window.
The code sample below works in production (web) mode, but when I try running it in hosted mode, IE detects XSS and overwrites the page with a single "#" to protect against the detected attack. I'm guessing this is because my GWT code server is running on localhost while the application I'm testing is deployed on a virtual machine.
Update: It appears that IE XSS Filtering is sporadic. Sometimes I'm able to get the page to load. But awhile later it starts filtering again.
public class MainWindow implements EntryPoint {
...
#Override
public void onModuleLoad() {
registerJSNIFunctions(this);
}
private native void registerJSNIFunctions(MainWindow mw) /*-{
$wnd.sayHi = function (name) {
mw.#MainWindow::sayHi(Ljava/lang/String;)(name);
}
}-*/;
public void sayHi(String name) {
alert("Hi " + name); // not valid, but you get the point
}
...
}
public class SecondWindow implements EntryPoint {
...
#Override
public void onModuleLoad() {
...
sayHi("kylos");
}
public static native void sayHi(String name) /*-{
$wnd.opener.window.$wnd.sayHi(name);
}-*/;
}
Any ideas on how I could get this to work in hosted mode? Or is there a better way to do cross-window communication with GWT?

Your question is quite interesting, see other´s opinion but I have done something similar using OAuth.
So, if the idea at the end is call from one Window to other some method I´d something like:
....
#Maybe if you use window instead of top works as well
$wnd.opener.top.location.replace(url);
$wnd.close();
....
....
And in the other browser wait for the new request, parse the url, and call "locally" to sayHi. Is this approach valid to you?
If you want further details about the Windows properties you can see W3Schools page
But basically:
$wnd.opener #returns Returns a reference to the window that created the window.
top #returns the topmost browser window

So the issue seems to be sporadic. I'm not sure how exactly the filter gets triggered, but when it does, the rewritten page gets cached by IE so future requests are guaranteed to fail until the browser cache is emptied.
I also found this Microsoft document that describes a custom header, X-XSS-Protection, that can be used to disable the filter. Obviously, this should only be used on a dev system in hosted mode.
To disable the filter, add the following header to your server configuration:
X-XSS-Protection: 0

Android WebView Javascript not enabled

I have the following code in my activity:
browser = (WebView)findViewById(R.id.webkit);
browser.getSettings().setJavaScriptEnabled(true);
browser.getSettings().setPluginsEnabled(true);
browser.getSettings().setDomStorageEnabled(true);
/*if (Build.VERSION.SDK_INT >= 16) {
browser.getSettings().setAllowFileAccessFromFileURLs(true);
browser.getSettings().setAllowUniversalAccessFromFileURLs(true);
}*/
// Loads html-string into webview
browser.loadUrl("file:///android_asset/index.html");
THe page loads fine, the css loads fine, the images all load fine. However I also have a local js file. WHich currently only contains an alert message alert("JSEnabled"); and yet the alert never appears. How can I go about diagnosing this?
I'm currently using the emulator to develop the project and have to support back to Gingerbread (2.3.3).
Incidently the same html / js works fine when I use the Browser app on the emulator (Pointing at a remotely served version of the same HTML / js)
I should also point out - all the files are in the assets folder in the project, and I've tried referencing the js as file:///android_assets/main.js and as main.js. I've even tried referencing the remote js file. Nothing works...

To work your javascript alert please add this to your webview
webview.setWebChromeClient(new WebChromeClient() {
#Override
public boolean onJsAlert(WebView view, String url, String message,
JsResult result) {
return super.onJsAlert(view, url, message, result);
}
});