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Created by Dr. Xi on August 31, 2008 20:43:44    Last update: January 22, 2011 12:48:08
It's probably more useful to make the JavaScript executor a bookmarklet. That way it gains access to the page on which it is invoked. Therefore, more helpful while debugging. Here's the code: <html> <body> <a href="javascript:(funct... Or, you can add this link to your bookmarks, name it "JS Executor". For a full featured JavaScript console, you may need Jash
Created by James on July 04, 2009 16:30:40    Last update: January 11, 2011 21:21:59
If you are looking for a solution for a progress bar, I direct you to the following resources: Bare Naked App provides a simple and elegant solution based on pure CSS with two images. You control the percentage of completion through the background-position attribute of the CSS. HTML: <img src="/images/percentImage.png" alt="... CSS: img.percentImage { background: white url(/imag... Images: (percentImage.png) (percentImage_back.png) WebAppers extended the above solution with JavaScript. They also added several colored images: JQuery UI has a built-in progress bar widget. However, if you want to get to understand some of the foobar needed to get CSS to work (in general) through this example, stay with me for the rest of this note. Initially I was thinking, a progress bar should be easy: just make...
Created by James on September 07, 2010 03:11:39    Last update: January 11, 2011 20:28:33
I didn't know how hard it was to vertically align something to the middle until I had to do it. An excellent writeup about the various techniques (or should I say hacks?) to achieve this is here: http://blog.themeforest.net/tutorials/vertical-centering-with-css/ Here I present a technique with the help of jQuery. To make it simple, what I'm doing is to display a single line of text in the middle of the page instead of at the top. The markup is made simple because the logic is moved to JavaScript. There are two requirements to make this work: The parent container uses relative positioning jQuery code added to re-position the content with absolute positioning <!doctype html> <html> <head> <title>Vert... For some reason, the following code did not work although...
Created by James on January 10, 2011 16:37:20    Last update: January 10, 2011 16:37:20
The following page injects CSS rules with JavaScript. It works fine in Firefox and Chrome. <html> <head> <script type="text/javascrip... But in IE, it breaks with "Unknown runtime error" (seemed like it's trying to interpret the curly brackets in the CSS as JavaScript blocks!): In order to make it work in IE, the code need to be changed to: <html> <head> <script type="text/javascrip... The tricks to identify IE and insert new CSS rules came from Paul Irish .
Created by James on June 30, 2010 19:04:45    Last update: July 03, 2010 21:24:33
Technically, file upload cannot be handled by Ajax, because XMLHttpRequest (XHR) does not handle file inputs. All techniques not using Flash rely on an invisible iframe as the upload form submit target. JavaScript then grabs the response content from the iframe and present it, giving the same illusion as Ajax. webtoolkit AIM The technique by webtoolkit is very simple. It involves 3 simple steps: include the AIM script, implement the start/finish JavaScript functions, and add an onsubmit handler to the normal file upload form. The hooked up form looks like: <head> <script type="text/javascript" src="webt... The AIM script is also quite simple: /** * * AJAX IFRAME METHOD (AIM) * http... The above code only supports HTML responses. In order to support JSON responses, the above...
Created by woolf on February 03, 2010 04:39:18    Last update: February 03, 2010 04:39:18
Ways to use JavaScript date function: // current time new Date(); new Date(0);...
Created by Dr. Xi on September 02, 2008 18:55:18    Last update: January 18, 2010 22:36:24
Remember the times when you googled for solutions to your technical problems? How much time did you spend on wading through the zillions of links to find the ones that are of interest to you? Wouldn't you hope that you can find the answer right away the second time around? How many times were you forced to peruse hundreds of pages of documentation for a very specific need? Did you ever need to experiment with various alternatives because the documentation was vague? Wouldn't you prefer that a shortcut is available when the same thing is needed again? Xinotes is here to record your technical findings so that you won't have to go through the same process again when the problem reappears. Experience has taught us...
Created by James on July 19, 2009 23:29:42    Last update: July 19, 2009 23:33:24
Existing techniques use background images to make round corners. I present a technique here that uses four foreground images: . I think this technique is easier to understand and use. The only requirements are: Add position: relative to the CSS for the box to be rounded Matching border and color between the box to be rounded and the corner images Here's the HTML with static elements: <!doctype html public '-//W3C//DTD HTML 4.01//EN' ... The markup is even easier if we use jQuery to add the corners dynamically: <!doctype html public '-//W3C//DTD HTML 4.01//EN' ... This is the result:
Created by Dr. Xi on October 04, 2008 03:29:55    Last update: October 04, 2008 04:26:40
<html> <body> <script language="JavaScript" ...
Created by Dr. Xi on September 07, 2008 22:10:21    Last update: September 07, 2008 22:15:51
When you use window.open to open a page in a new browser window, the new window is not modal, i.e., focus on the new window can be lost when the parent window is clicked. IE provides window.showModalDialog but it doesn't have the full power of a real browser window, and it's IE specific. This is a JavaScript that makes the popup window modal. The central trick is to check focus periodically with window.setInterval and request focus when it's lost. In IE, when an input on the page gets focus, the window thinks that it lost focus and requests focus back, thus taking focus away from any input fields - making it impossible to enter data into input fields in the modal dialog. This problem is...
Created by Dr. Xi on September 01, 2008 01:01:59    Last update: September 02, 2008 15:55:05
In JavaScript, null is not the same as "undefined". The value null is an object, while "undefined" is, well, undefined. However, for undefined variable a , if (a){...} throws exception, but if (window.a) {...} returns false , even though they are the same thing! // 1. for undefined variable a, typeof functio...