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Element shifting when updating text attribute

Here's what I'm looking at. I have a text element:
var label = paper.text(100, 100, "Test String").attr({some attrs});
It appears where I want it to and everything is good. The problem comes when I go to update the text attribute later.
label.attr({text: "My new label text"});
When I do this the text element gets shifted a small amount in the positive y direction, so downward.
When I check the x and y position values before and after the change they are identical. I have no idea what to do. I noticed it not happen once in a friends browser, Chrome, which is the same one I'm using.
Any ideas? I'd rather not have to alter the y value every time I change the text attr.
Thanks in advance for any help!

I don't know if this is feasible for your project, but you can try combining your raphael elements with standard html elements. Your label could be a div that is positioned and styled with jQuery. If you need to dynamically change the text of the label, you can just use the jQuery .html() attribute for the div, which will not change its position. This might not be the most elegant solution, but integrating jquery and raphael works well in most situations and guarantees standardization of text positioning/styling across browsers.

How to get nth line of a text by JavaScript?

Consider a simple html element as
<div id="test">
a long text without line break
</div>
The browser will create lines based on the glyph and font sizes. After text arrangement by the browser (e.g. depending on the window width), how to get the lines of the text by JavaScript?
For example:
How to get the total number of lines
How to get the first line as appeared in the current window?
How to get the nth line?

No, there is no API that gives you access to the rendered text after layout has occurred. The only way to approximate this is pretty hacky, i.e. add words into a container one at a time and see when it changes height. See this related question:
detecting line-breaks with jQuery?
Yeah, who'd have thought it, even jQuery doesn't do this! ;-)

2 easy solutions and a extremely hard one.
1 Formatting the text.
Inside a pre & textContent
html
<pre>hello
hello1
hello2</pre>
js
document.getElementsByTagName('pre')[0].textContent.split('\n')
http://jsfiddle.net/gq9t3/1/
2 Adding br's
Inside a div with br & textContent
html
<div>hello<br>hello1<br>hello2<br>pizza</div>
js
document.getElementsByTagName('div')[0].innerHTML.split('<br>')
http://jsfiddle.net/gq9t3/4/
To much trouble
css
div{width:100px;line-height:20px;}
html
<div>hello dfgfhdhdgh fgdh fdghf gfdh fdgh hello1gfhd gh gh dfghd dfgh dhgf gf g dgh hello2</div>
js
document.getElementsByTagName('div')[0].offsetHeight/20
easy way to find the number of lines but you need to calculate the text width to find the corresponding line content.
http://jsfiddle.net/gq9t3/3/

I was attempting to style the first line of text, but text-transform:uppercase messed it up. http://zencode.in/lining.js/ helped with addressing the first line (responsively!), so perhaps this library will assist with your issue too.

full div area onclick

This problem was not solved.. it was just evaded.. so dont use this as reference
what i have is
<div>
<img onclick='this.style.display="none";this.parentNode.getElementsByTagName("div")[0].style.display="block";this.parentNode.getElementsByTagName("div")[0].style.width=this.offsetWidth+"px";this.parentNode.getElementsByTagName("div")[0].style.height=this.height+"px";' src='http://static.***.pl/cache/***.pl/math/cafc682a15c9c6f1b7bb41eb004d6c45935cbf06434221f7201665f85242cb94.png'/>
<div onclick='this.style.display="none";this.parentNode.getElementsByTagName("img")[0].style.display="inline";' style='display:none'>
<pre style='width:100%;height:100%;'>
\lim_{t\to\infty}\int\limits_1^{t} \frac{1}{x^2}\,dx=\lim_{t\to\infty}\left(-\frac{1}{x}\right)\bigg|_1^t=\lim_{t\to\infty}\left(-\frac{1}{t}-\left(-\frac{1}{1}\right)\right)=\kappa=1880154404
</pre>
</div>
</div>
yes i know its ugly but well..
my problem is when i click the image it does what i want but if i then click the div it only works if i click on the text and i want it to work for the full div !
i dont want to use document.getElementById etc...
there will be multiple instances of this code and it will be in unknown places.
i really dont want to write up bloated code to do this (this includes jQuery,flash,.NET, Zend Engine etc etc...)
my question is simple :
why the hell does it work only if i click on text and how to fire onclick for the whole div

In your original Javascript action, you were setting the width and height of your div to zero, which means that there is no area to click on.
Here is a demo: http://jsfiddle.net/audetwebdesign/ndKqM/
which should demonstrate the fix. I added some background color and padding to show the dimensions of the various boxes.
I removed the parts of the JS that calculated width and height and that fixed the issue.
If you click on the lime green area that holds your text, the action works.
Unless there is some other reason, you don't need to adjust width or height.

It's hard to tell what behavior you really want.
You are setting the image to display:none, and then you set the style.height and style.width of the sibling div to image.height and image.width. So - those will both be zero (as display:none is set for the image).
Do yourself a favor and set background colors or borders for your divs so you can see what's going on as you code.

Use an A tag with your onclick event and a null URL href="javascript://" instead of a DIV

javascript based progress bar

I am curious how can a javascript (or also benefiting from jquery) based progress indicator such can be developed:
alt text http://img707.imageshack.us/img707/3295/dealindicator.png
My first idea is something such as:
function drawBar(total,sofar){
.........................
}
where it consumes the max number(20 in our case) and sofar (15 for the picture).
But how can it be implemented?
Is there any jquery based plugin to achieve this?
Regards

This is usually done with CSS, by creating a div the total size of your progressbar, and then having another div child of that which has a percentage width of how much needs to be filled.
You can style the divs anyway you want. You likely want to style the inner div with background-color, or background-image & background-repeat. It can be a solid colour, a gradient, or a banded pattern, which seems to be rather popular.
Have you Google'd for jQuery plugins? They are fairly easy to find. Here's one for example: http://t.wits.sg/jquery-progress-bar/

JavaScript: Check width of a <div> object before placing it

Consider:
$("#PlotPlace").append('<div style="position:absolute;left:200px;top:40px;font-size:smaller">Hello world!</div>');
I need to execute that line only if the width of the resultant text would be less than 60px. How can I check the width before placing the object?

Unfortunately, the div will only have a width value once it is rendered into the DOM.
I would append that content to an inconspicuous area of the document, perhaps even absolutely positioned so that no flow disruption occurs, and make sure that it is set to "visibility:hidden". That way it will be inserted into the DOM and be rendered, but be invisible to the viewer.
You can then check the width on it, and move it into position and set it to "visibility:visible" at that point. Otherwise, you can remove it from the document.

Maybe you can append it invisible, then check it's width, and then consider to show or hide.

$("#PlotPlace").append('<div style="position:absolute;left:9001px;top:40px;font-size:smaller">Hello world!</div>');
var div = $('#PlotPlace').children("div");
if(div.width() < 60)
div.css({left:200})

Sounds like something you'd have to hack. I don't believe the JavaScript runtime in any browser has an event you can hook into in between calculating the layout and displaying the element, so you can add it in a way that it can't be seen and doesn't affect the height (doesn't cause additional scrolling), and then show/hide it based on the width at this point. It's hacky and ugly, but because you don't have many event hooks it might be the only way to do it.

You can´t. At least not so easy. The text you insert is written in a specific font, which must be rendered by the browser, then you know the width of the element. By the Way, what exactly do you want to insert, with such a restriction? Wouldn´t it be simpler to cut the text within the output parameters?