There seem to be a know issue with IE which doesn't respond to URLs that have # sign in them.
See for example: https://mootools.lighthouseapp.com/projects/2706/tickets/638-request-fails-when-url-has-hash-in-ie7
As we use # quite frequently in out GWT based application we are lacking support for IE7 users who want to browse the site.
Is there any known workaround for GWT other than modifying the URL?
History works perfectly well in our GWT app in all IE versions...
That ticket was about XMLHttpRequest, so do not use hashes in your xmlhttprequests. It has nothing to do with GWT.
First of all, the problem described in the supplied link is related with URLs that you query with XMLHttpRequest. In GWT application # can appear in ordinary GET request (when you are opening the page, that is when you are starting your GWT application). When GWT does XMLHttpRequest request, it uses URLs similar to:
http://yourserver.com/context/com.yourcompany.SomeModule/someService
There is no # in it, so if you have any problems, they are not related with this issue.
I think I finally figured out what the problem is.
Our gwt application is sitting as an iframe inside another HTML file so setting the gwt history support
<iframe src="javascript:''" id="__gwt_historyFrame" tabIndex='-1' style="position:absolute;width:0;height:0;border:0"></iframe>
has to be done in the outer HTML rather than the gwt one.
This gwt script was meant to support browsers such as IE6 and IE7 which don't have the onhashchange event implemented.
Related
I am working on a webapplication that uses caching to make it available offline. Everything works fine when running it chrome (offline and online). But when I run it on iPad the links don't work anymore and I get failed to load page everywhere. Removing the caching makes the links work again so it obviously has something to do with the caching. Navigating directly to the seperate pages of the webapp also works fine in Safari, its the link that causes the error. By default all links are loaded with AJAX in jQuery Mobile. Changing this by adding rel="external" also fixes the problem, but obviously I don't want to do that.
To enable caching I added this code: and created a manifest file with ALL the files (scripts, css, images, html). Does anyone know what the problem could be?
I've experienced this as well while working with caching using manifests. What I discovered was that there Chrome has no limits. iPad and iPhone do. This appears to be pretty small, around 5mb. Try removing images as much as possible and using YUI Compressor on your scripts.
Ajax requests can be cached actually, the system doesn't care if the request is by AJAX or normal full request. All you have to do is put the URLs you wanted to retrieve by ajax into the manifest like the rest of the assets.
Hope this helps
I need for users to upload files (mostly images) without leaving the current webpage. What's the best tool, library or mechanism for doing this? I'm using the latest jQuery and Spring webmvc (with JSP), so if there's already a mechanism within them then that's ideal.
It would also be really great to have some kind of progress bar. Does that mean it requires coordination with the server to read the progress (where Spring would have to come into play)? Or is there a mechanism within JavaScript for this?
You should check out Plupload.
Plupload offers a cross-browser
JavaScript File uploading API that
handles multiple file uploads,
client-side progress meters, type
filtering and even client-side image
resizing and drag-and-drop from the
desktop. It achieves all of this by
providing backends for Flash,
Silverlight, Google Gears, HTML5 and
Browserplus and picking the most
capable available option.
Its really neat! Here's a link to some of their Demos...
http://www.plupload.com/example_jquery_ui.php
... and a screenshot of the jQuery UI queue widget (it has a progress bar!):
I hope this helps.
Hristo
I use uploadify pretty regularly: http://www.uploadify.com/
However it does use flash for the upload mechanism and as a result may create some issues if the user is authenticated.
You should use AJAX on the client side
http://www.webtoolkit.info/ajax-file-upload.html This tutorial covers all client side.
Om the server side
This tutorlal covers most of this issue:
http://www.ioncannon.net/programming/975/spring-3-file-upload-example/
Yopu can use jquery as well or any other JS framework.
But the mist important thing is the fact You need to remember that your tag on client side should have.
enctype='multipart/form-data'
property. it means that your request contains muultipart data.
Uploadify does that trick > http://www.uploadify.com/
All samples are php but you should be able to convert it to your platform.
Facebook is doing Ajax History (Back and Forward button) and Bookmark using #! instead of just # in the URL. Is it always a good idea to do that, because I was thinking that a usual anchor could interfere with the Ajax History mechanism to trigger it into processing a normal anchor.
So, the Ajax History function will only process a hash portion only when it sees #! instead of just #.
And is using ! compatible with major browsers? If Facebook is using !, a guess is that it may be fairly well supported.
See Google's Making AJAX Applications Crawlable
for a possible use case (don't know if this is why Facebook used this fragment).
Update: This answer has been superseeded by this article. It discusses the issues with the Hashbang (#!), Hashes (#) and the HTML5 History API (pushState, popState) and the solutions.
In regards to usability on your website, it doesn't matter and you can use anything you like.
In regards to search engine optimization, having it and not having it both provide different avenues to go down.
For instance, Facebook uses the ! according to the Google Proposal for Making Ajax Applications Crawlable. Adding the ! will tell google that it should listen in on that ajax request and add that url to search engine results. This is great for websites which have already implemented ajax, as all you need to do is add the !.
The downside of this is that it only solves the problem of making your ajax crawlable. It does not solve the problems of:
Keeping the URLs clean and consistent for Ajax and Non-Ajax users. Eg. you could end up with www.facebook.com/profile.php?pid=123#!profile.php?pid=123
Keeping the website accessible by Non-Ajax users.
Keeping the URLs the same for both Ajax and Non-Ajax users.
Requires some severely complicated server side changes for escaping and translation of states in regards to query strings.
It is not compatible with the new HTML5 PopState functionality which is designed to truly solve these problems.
For websites which don't currently use ajax for everything, due to the problems above it is far better NOT using the Google Proposal as it is only workaround for sites like facebook which went ajax crazy and needed a desperate solution to SEO. There are alternatives which solve more of these problems (and with the HTML5 PopState now available can solve all the problems). One such alternative is jQuery Ajaxy (as seen on balupton.com) which works by simply upgrading your website into a ajax application, while keeping the experience for a Ajax-Enabled rich and interactive and continuing to work perfectly for Ajax-Disabled users.
I need to create a portable script to give to others to implement on their websites that will dynamically show content from my database (MySQL).
I know AJAX has a cross-site problem, but it seems that Google's ad's somehow manage the effect in a cross-browser / cross-site fashion.
Knowing that I have to give people a simple cut/paste snippet to put in their website...how can I achieve this? How did Google?
They use an <iframe>, so the ad is served from their server, and can talk to their database. I'm not actually sure that they use any sort of AJAX from their ads, though; they appear to just be mostly static content, with a few scripts for tweaking the formatting (which are optional, since they want their ads to be visible even if users have JS turned off).
Remember, you can always look into this on your own, and see what they did. On Firefox, use Firebug to explore the html, css, and scripts on a site. On WebKit based browsers (Safari, Chrome, and others), you can use the Web Inspector.
Google's ad code is loaded via a script tag that calls a remote javascript file. The AJAX restrictions that are generally enforced with xmlhttp, iframe, and similar AJAX requests don't apply when it comes to loading remote javascript files.
Once you've loaded the javascript file, you can create iframes in your page that link back to the actual hosted content on your server (and feed them any data about the current page that you wish).
jQuery has built in support for jsonp in their ajax calls. You may want to lookin in to using that if you are really needing to use ajax.
http://api.jquery.com/
http://docs.jquery.com/Ajax
You don't need iFrames and you don't need AJAX. It's really, really simple!
You pull in a remote JS file that is actually a constructed file from php/asp/whatever. In your JS file you have a document.write script that writes the content. It's that simple.
We do this all the time with media stored on separate sites. Here's an example.
YOUR SERVER: file.php (which outputs js)
<script>
document.write("I'm on a remote server");
</script>
OTHER SITE:
<script src='http://www.yourserver.com/file.php'></script>
And it will output the content generated by the script. To make the content customized you can put in script vars above the script call that will adjust what your file pulls out. From there it's pretty straightforward.
I realize this question is a year old, but I've written a library that can help with the document.write part of the problem (whether this is a TOS violation, I don't know) writeCapture.js. It's pretty simple:
$('#ads').writeCapture().html('<script src="whatever-your-adsense-code-is"> </script>');
The example uses jQuery, but you can use it standalone as well.
Right now i'm building a firefox plugin that duplicates some functionality on my website. It takes in an email address and then returns information to the user. The easiest way to do this in the plugin is to use an Iframe and render that super simple form on my website. All of this works great, but to make the plugin really useful, i would like the plugin to have access to the information that the iframe renders, so it can use it in the current window that the user is in.
Is it possible to pass information back through an Iframe in this manner? I know there are quite a few domain access restrictions with Iframes, so any help or insight is appreciated!!
I've done this two ways.
If the iframe is on the same domain as the parent website, you can just, in javascript, access window.parent.
If it isn't, however...I've done a dirty trick. I'll share it here, though, as it may help.
We created a page on the other domain, which would call to window.parent.parent. We put that in a hidden iframe inside the iframed page, and send it a querystring argument or two. It's not pretty, but it gets around cross-domain scripting problems.
This basically means that you have this sort of thing:
admin.example.com
content.example.com - iframe
admin.example.com?contentid=350 - hidden iframe that makes a window.parent.parent call.
Is the point of this whole exercise functional testing of your website? If so, instead of your custom Firefox plugin, consider using Selenium to automate interactions with websites. It works with all major browsers and supports the inspection of page elements you are trying to do (using XPath). It also features a Firefox plugin called Selenium IDE that allows you to conveniently "record" your interactions with a website for automated playback later.