I have an applet which communicates with the browser via javascript. I load the applet, and some javascript, in an iframe, and in Windows 2000 with IE6, I have determined that the messages the applet propagates hit the parent frame, rather than the iframe.
Is there a better solution to fix this than include windows2k.hacks.js, with proxy methods for each method the applet calls? Someone please tell me there's a simpler solution than this.
How are you sending the messages back to the frame?
Generally its
JSObject myWin = JSObject.getWindow(this);
myWin.call("JsFunction", "My Message");
It sounds like you might be using jActivating. This library does not work with IE6 and Win2k for some reason, so just scan the useragent and guard against this specific configuration.
Related
GWT is used and the application is deployed on WebLogic using HTTPS.
The performance is poor and with F12 Developer Tools, we could see that blank.html is downloaded multiple times. This is clearly related to GWT but we have not been able to figure out why.
The following is from javascript:
defineSeed(2613, 2614, makeCastMap([Q$BaseModelData, Q$ModelData, Q$Theme, Q$Serializable]), Slate_0);
var SLATE;
function $clinit_GXT(){
$clinit_GXT = nullMethod;
IMAGES = new XImages_generatedBundle_0;
MESSAGES = new XMessages__0;
SSL_SECURE_URL = getModuleBaseURL() + 'blank.html';
}
This is from GWT.java:
/**
* URL to a blank file used by GXT when in secure mode for iframe src to
* prevent the IE insecure content. Default value is 'blank.html'.
*/
public static String SSL_SECURE_URL = GWT.getModuleBaseURL() + "blank.html";
Does anyone know under what circumstances blank.html is called?
Thanks!
This is from GWT.java:
This is actually from GXT.java.
This is used in a few cases when creating an <iframe> element, so that IE won't give errors if your site is hosted from SSL. I can actually only find one case (as of GXT 3.1.1) which uses this, in Layer.java. Only IE pages loaded from https urls will make use of this.
The Layer class uses this as a "shim", a way to prop up some DOM elements above overs, and work around some browser bugs (typically plugin or iframe related). Menus and popup dialogs use this to ensure that they don't appear "underneath" content that they should be "above".
This file is very small - just enough HTML to convince IE than the iframe has correctly loaded, and no more. It never changes, and should load nearly instantly.
As far as performance goes, this should only happen when a Menu or Window/Dialog/Tooltip is shown - these shouldn't be happening on app startup usually, at least not more than a window or two. Additionally, the browser should recognize that it is loading the same element and cache it correctly, and not load it multiple times (though it might be listed several times as hitting the cache). If the server has instructed the browser to never cache the file, that is something you should look at changing.
In short, this is very unlikely to be the cause of any performance issues, at least in GXT itself. If somehow you have the shim enabled on every single widget in your project, this should not be required. If the file is loading slowly, something may be very wrong with your server configuration.
For reference, here is the entire file:
<html></html>
I am trying to download a file from server. The normal GWT RPC call doesnot allow me to do that, and hence I wrote a servlet to do that job for me. From the client side, I am creating a Frame object, and I set the servlet URL in it, and add that frame Object in my root panel.
When I execute this in IE, a window pops up asking for Save/Open file.
But when I execute the same in a Firefox or a Google Chrome browser, nothing is happing.
I am not getting any request on my servlet/server side.
Here is a slice of the code :-
String servletUrl = "http://localhost:13080/Browser/ui/dataExportServlet?level=ZERO";
Frame frame = new Frame(servletUrl);
frame.setVisible(false);
RootPanel.get().add(frame);
So, can someone please help me out.
This might be related to same origin policy.
Are both servlet and webapp running on port 13080?
If they differ, SOP might fail this.
If I understand correctly, IE has a more relaxed policy so it might work there but not in chrome.
See http://en.wikipedia.org/wiki/Same_origin_policy and Can I disable SOP (Same Origin Policy) on any browser for development?
In Chrome, you can use the Developer Tools (CTRL + SHIFT + I) to check if the IFrame is being added to the HTML, and if the frame's source is being set properly. You should also be able to see what content has been loaded into the iframe.
Alternately, set a breakpoint in your servlet to see if the iframe is being hit at all from Chrome.
I got the solution for this issue.
I removed the frames and added the following code :-
com.google.gwt.user.client.Window.open(url, "CSVDownload", "");
Now, this opens a new browser window, and then I get the pop-up to open/save the server side file in all 3 web-browsers. (IE, Mozilla FireFox, Chrome).
Thanks a lot!!!
I want to use the #! token to make my GWT application crawlable, as described here:
http://code.google.com/web/ajaxcrawling/
There is a GWT sample app available online that uses this, for example:
http://gwt.google.com/samples/Showcase/Showcase.html#!CwRadioButton
Will serve the following static webpage to the googlebot:
http://gwt.google.com/samples/Showcase/Showcase.html?_escaped_fragment_=CwRadioButton
I want my GWT app to do something similar. In short, I'd like to serve a different flavor of the page whenever the _escaped_fragment_ parameter is found in the URL.
What should I modify in order for the server to serve something else (a static page, or a page dynamically generated through a headless browser like HTML Unit)? I'm guessing it could be the web.xml file, but I'm not sure.
(Note: I thought of checking the Showcase app provided with the GWT SDK, but unfortunately it doesn't seem to support serving static files on _escaped_fragment_ and it doesn't use the #! token..)
If you want to use web.xml, then I think it won't work with a servlet-mapping, because the url-patterns ignore the get parameters. (Not 100% sure, if there is another way to make this possible.)
You could of course map Showcase.html to a servlet, and in that servlet decide what to do, based on the get parameter "_escaped_fragment_". But it's a little bit expensive to call a Servlet just to serve a static page for the majority of the requests (not too bad, but still. You could set cache headers, if you're sure that it doesn't change).
Or you could have an Apache or something in front of your server - but I understand, I wouldn't like to have to do that either. Maybe your JavaEE server (which one are you using BTW?) provides some mechanism for URL filtering before the request gets passed on to the web container - I'd like to know that, too!
Found my answer! The Showcase sample supporting crawlable hyperlinks is in the following branch:
http://code.google.com/p/google-web-toolkit/source/browse/branches/crawlability/samples/showcase/?r=7726
It defines a filter in the web.xml to redirect URLs with the _escaped_fragment_ token to the output of HTML Unit.
i'm writing a web application that works with an external dll (activex),
the dll was written by skype developers,
the problem is that,
in a case of any event (status changing, attachment, etc..) in the client side, a delegate needs to be call on the server side.
so when i'm changing a status in the skype program, it seem that a postback really happen but there is no affect on the client side.
for example , i'm trying to change a label content by his new value from the server side (using label that runat server) but nothing change.
i succedded to make a java script interval
so when it recognize any changes
it replace the content of the label.
i preffer not to use it because the dll already support that events.
thanks in advance.
It seems that your problem is simulating a post-back to make the label change its contents. If so, this link might be helpful:
Using doPostBack Function in asp.net
We've got an Eclipse RAP application that's behaving a bit strangely in Firefox - two distinct problems.
When you browse around, you can click on a button in one part of the system. This opens a popup window like so:
IWorkbenchBrowserSupport bs;
bs = PlatformUI.getWorkbench().getBrowserSupport();
int style = IWorkbenchBrowserSupport.AS_EXTERNAL;
IWebBrowser b = bs.createBrowser(style, getRandomID(), "Hello world", "");
b.openURL(new URL(...));
where the URL is another servlet in the application. This servlet is in the same runtime, but has nothing to do with RAP - it takes a binary blob from in-memory storage and dumps it in the output stream.
Problem 1: This causes the HTTP session to die in firefox, and shows the "session expired" RAP error page with a link to restart the session.
Problem 2: Now, when you click on the link to restart the session, it shows the application's dialog again, but the session expired error is shown again the moment you do anything. This prevents the user from using the system again, unless Firefox is closed down completely and restarted. A quick peek with FireBug reveals that the JSESSIONID passed by Firefox does not change.
Has anyone seen this before?
How long is the dumping of the stream to the output? May it cause a timeout? As RAP uses Javascript calls, it might be much shorter than the normal timeout time.
For problem 2: Firefox caches a lot of things; and if the Javascript execution hangs, it might cause such problems.
Are these problems present in other browsers? It might be a good idea to check with the internal browser (or any other browser with a different rendering engine).
It turns out that if a RAP application opens a popup window pointing to a servlet in the application itself, inside the current HTTP servlet context, the session is killed. Fixed by creating a dummy HTTP context for the servlet in question.
If you need to deliver content from within the same application, you should use a service handler instead. See this FAQ:
http://wiki.eclipse.org/RAP/FAQ#How_to_provide_download_link.3F