Hi I am trying to use getBoundingClientRect javascript function but the problem is this only seems to work for 1 of my elements. Here is the code.
function getDataXML(getID, cellId) {
var divMain = document.getElementById('Main');
var divCell = document.getElementById(cellId);
var divHoverControl = document.getElementById(getID);
var rectMain = divHoverControl.getBoundingClientRect();
var rectCell = divCell.getBoundingClientRect();
var divWidth = divHoverControl.offsetWidth;
var cellWidth = divCell.offsetWidth;
alert(rectMain.left + " " + rectMain.right + " " + divWidth + " " + cellWidth);
}
Its seems as though the page gets the elements using there ID correctly as I get no error and setting some style attributes works for each element but I only seem to get a result for my rectCell and cellWidth variables but the exact same code for rectMain and DivWidth dont seem to work. Any help would be greatly appreciated.
I'm struggling with managing dynamically built event handlers in javascript.
In several places, I build forms, or controls in which specific events (mainly mouseovers, mouse-outs, clicks) need to be handled.
The trick is that in a significant number of cases, the event handler itself needs to incorporate data that is either generated by, or is passed-into the function that is building the form or control.
As such, I've been using "eval()" to construct the events and incorporate the appropriate data, and this has worked somewhat well.
The problem is I keep seeing/hearing things like "You should never use eval()!" as well as a couple of increasingly ugly implementations where my dynamically-built event handler needs to dynamically build other event handlers and the nested evals are pretty obtuse (to put it mildly).
So I'm here, asking if someone can please show me the better way (native javascript only please, I'm not implementing any third-party libraries!).
Here's a crude example to illustrate what I'm talking about:
function CreateInput(controlName,type,activeStyle,dormantStyle,whenClicked)
{
var inp = document.createElement('input');
inp.id = controlName;
inp.type = type;
inp.style.cssText = dormantStyle;
eval("inp.onfocus = function() { this.style.cssText = '" + activeStyle + "'; }");
eval("inp.onblur = function() { this.style.cssText = '" + dormantStyle + "'; }");
eval("inp.onclick = function() { " + whenClicked + "; }");
return inp;
}
This function obviously would let me easily create lots of different INPUT tags and specify a number of unique attributes and event actions, with just a single function call for each. Again, this is an extremely simplified example, just to demonstrate what I'm talking about, in some cases with the project I'm on currently, the events can incorporate dozens of lines, they might even make dynamic ajax calls based on a passed parameter or other dynamically generated data. In more extreme cases I construct tables, whose individual rows/columns/cells may need to process events based on the dynamically generated contents of the handler, or the handler's handler.
Initially, I had built functions like the above as so:
function CreateInput(controlName,type,activeStyle,dormantStyle,whenClicked)
{
var inp = document.createElement('input');
inp.id = controlName;
inp.type = type;
inp.style.cssText = dormantStyle;
inp.onfocus = function() { this.style.cssText = activeStyle; };
inp.onblur = function() { this.style.cssText = dormantStyle; };
eval("inp.onclick = function() { " + whenClicked + "; }");
return inp;
}
...but I found that whatever the last assigned value had been for "activeStyle", and "dormantStyle" became the value used by all of the handlers thusly created (instead of each retaining its own unique set of styles, for example). That is what lead me to using eval() to "lock-in" the values of the variables when the function was created, but this has lead me into nightmares such as the following:
(This is a sample of one dynamically-built event-handler that I'm currently working on and which uses a nested eval() function):
eval("input.onkeyup = function() { " +
"InputParse(this,'ucwords'); " +
"var tId = '" + myName + This.nodeName + "SearchTable" + uidNo + "'; " +
"var table = document.getElementById(tId); " +
"if (this.value.length>2) { " +
"var val = (this.value.indexOf(',') >=0 ) ? this.value.substr(0,this.value.indexOf(',')) : this.value; " +
"var search = Global.LoadData('?fn=citySearch&limit=3&value=' + encodeURI(val)); " +
"if (table) { " +
"while (table.rows.length>0) { table.deleteRow(0); } " +
"table.style.display='block'; " +
"} else { " +
"table = document.createElement('table'); " +
"table.id = tId; " +
"ApplyStyleString('" + baseStyle + ";position=absolute;top=20px;left=0px;display=block;border=1px solid black;backgroundColor=rgba(224,224,224,0.90);zIndex=1000;',table); " +
"var div = document.getElementById('" + divName + "'); " +
"if (div) { div.appendChild(table); } " +
"} " +
"if (search.rowCount()>0) { " +
"for (var i=0; i<search.rowCount(); i++) { " +
"var tr = document.createElement('tr'); " +
"tr.id = 'SearchRow' + i + '" + uidNo + "'; " +
"tr.onmouseover = function() { ApplyStyleString('cursor=pointer;color=yellow;backgroundColor=rgba(40,40,40,0.90);',this); }; " +
"tr.onmouseout = function() { ApplyStyleString('cursor=default;color=black;backgroundColor=rgba(224,224,224,0.90);',this); }; " +
"eval(\"tr.onclick = function() { " +
"function set(id,value) { " +
"var o = document.getElementById(id); " +
"if (o && o.value) { o.value = value; } else { alert('Could not find ' + id); } " +
"} " +
"set('" + myName + This.nodeName + "CityId" + uidNo + "','\" + search.id(i)+ \"'); " +
"set('" + myName + This.nodeName + "ProvId" + uidNo + "','\" + search.provId(i)+ \"'); " +
"set('" + myName + This.nodeName + "CountryId" + uidNo + "','\" + search.countryId(i) + \"'); " +
"set('" + input.id + "','\" + search.name(i)+ \"'); " +
"}\"); " +
"var td = document.createElement('td'); " +
"var re = new RegExp('('+val+')', 'gi'); " +
"td.innerHTML = search.name(i).replace(re,'<span style=\"font-weight:bold;\">$1</span>') + ', ' + search.provinceName(i) + ', ' + search.countryName(i); " +
"tr.appendChild(td); " +
"table.appendChild(tr); " +
"} " +
"} else { " +
"var tr = document.createElement('tr'); " +
"var td = document.createElement('td'); " +
"td.innerHTML = 'No matches found...';" +
"tr.appendChild(td); " +
"table.appendChild(tr); " +
"} " +
"} else { " +
"if (table) table.style.display = 'none'; " +
"} " +
"} ");
Currently, I'm having problems getting the nested eval() to bind the ".onclick" event to the table-row, and, as you can see, figuring out the code is getting pretty hairy (debugging too, for all the known reasons)... So, I'd really appreciate it if someone could point me in the direction of being able to accomplish these same goals while avoiding the dreaded use of the "eval()" statement!
Thanks!
And this, among many other reasons, is why you should never use eval. (What if those values you're "baking" in contain quotes? Oops.) And more generally, try to figure out why the right way doesn't work instead of beating the wrong way into submission. :)
Also, it's not a good idea to assign to on* attributes; they don't scale particularly well. The new hotness is to use element.addEventListener, which allows multiple handlers for the same event. (For older IE, you need attachEvent. This kind of IE nonsense is the primary reason we started using libraries like jQuery in the first place.)
The code you pasted, which uses closures, should work just fine. The part you didn't include is that you must have been doing this in a loop.
JavaScript variables are function-scoped, not block-scoped, so when you do this:
var callbacks = [];
for (var i = 0; i < 10; i++) {
callbacks.push(function() { alert(i) });
}
for (var index in callbacks) {
callbacks[index]();
}
...you'll get 9 ten times. Each run of the loop creates a function that closes over the same variable i, and then on the next iteration, the value of i changes.
What you want is a factory function: either inline or independently.
for (var i = 0; i < 10; i++) {
(function(i) {
callbacks.push(function() { alert(i) });
})(i);
}
This creates a separate function and executes it immediately. The i inside the function is a different variable each time (because it's scoped to the function), so this effectively captures the value of the outer i and ignores any further changes to it.
You can break this out explicitly:
function make_function(i) {
return function() { alert(i) };
}
// ...
for (var i = 0; i < 10; i++) {
callbacks.push(make_function(i));
}
Exactly the same thing, but with the function defined independently rather than inline.
This has come up before, but it's a little tricky to spot what's causing the surprise.
Even your "right way" code still uses strings for the contents of functions or styles. I would pass that click behavior as a function, and I would use classes instead of embedding chunks of CSS in my JavaScript. (I doubt I'd add an ID to every single input, either.)
So I'd write something like this:
function create_input(id, type, active_class, onclick) {
var inp = document.createElement('input');
inp.id = id;
inp.type = type;
inp.addEventListener('focus', function() {
this.className = active_class;
});
inp.addEventListener('blur', function() {
this.className = '';
});
inp.addEventListener('click', onclick);
return inp;
}
// Called as:
var textbox = create_input('unique-id', 'text', 'focused', function() { alert("hi!") });
This has some problems still: it doesn't work in older IE, and it will remove any class names you try to add later. Which is why jQuery is popular:
function create_input(id, type, active_class, onclick) {
var inp = $('<input>', { id: id, type: type });
inp.on('focus', function() {
$(this).addClass(active_class);
});
inp.on('blur', function() {
$(this).removeClass(active_class);
});
inp.on('click', onclick);
return inp;
}
Of course, even most of this is unnecessary—you can just use the :focus CSS selector, and not bother with focus and blur events at all!
You don't need eval to "lock in" a value.
It's not clear from the posted code why you're seeing the values change after CreateInput returns. If CreateInput implemented a loop, then I would expect the last values assigned to activeStyle and dormantStyle to be used. But even calling CreateInput from a loop will not cause the misbehavior you describe, contrary to the commenter.
Anyway, the solution to this kind of stale data is to use a closure. JavaScript local variables are all bound to the function call scope, no matter if they're declared deep inside the function or in a loop. So you add a function call to force new variables to be created.
function CreateInput(controlName,type,activeStyle,dormantStyle,whenClicked)
{
while ( something ) {
activeStyle += "blah"; // modify local vars
function ( activeStyle, dormantStyle ) { // make copies of local vars
var inp = document.createElement('input');
inp.id = controlName;
inp.type = type;
inp.style.cssText = dormantStyle;
inp.onfocus = function() { this.style.cssText = activeStyle; };
inp.onblur = function() { this.style.cssText = dormantStyle; };
inp.onclick = whenClicked;
}( activeStyle, dormantStyle ); // specify values for copies
}
return inp;
}
I can't figure out why this script isn't working in IE7 and 8. It works fine in all other browsers, but for some reason, in IE7 and 8 this script is only firing the // thumbs hover bit, and not the // loading images bit (which is actually more important). Everything seems to be fine, does anyone have any ideas?
function featuredJS() {
$("[title]").attr("title", function(i, title) {
$(this).data("title", title).removeAttr("title");
});
// loading images
var last = "featured/01.jpg";
$("#thumbs a").click(function(event) {
event.preventDefault();
var position = $(this).attr("class");
var graphic = $(this).attr("href");
var title = $(this).attr("alt");
var description = $(this).data("title");
var currentMargin = $("#full-wrapper #full").css("marginLeft");
var currentWidth = $("#full-wrapper #full").css("width");
var transitionTest = currentMargin.replace("px", "") * 1;
if(last != graphic && ((transitionTest % 938) == 0 || transitionTest == 0)) {
$("#placeholder").before( "<div class='featured'><div class='description " + position + "'>" + "<h3>" + title + "</h3>" + "<p>" + description + "</p>" + "</div><img src=\"" + graphic + "\" /><div style='clear:both;'></div></div>" );
$("#full-wrapper #full").animate({
marginLeft: "-=938px"
}, 500);
$("#full-wrapper #full").css("width","+=938px");
last = graphic;
};
});
// thumbs hover
$("#thumbs .thumb").hover(
function () {
$(this).find(".red-bar").animate({height:"72px"},{queue:false,duration:500});
},
function () {
$(this).find(".red-bar").animate({height:"3px"},{queue:false,duration:500});
}
);
};
Demo page at http://www.weblinxinc.com/beta/welex/demo/
Your problem is caused by not having a margin set to begin with. transitionTest then becomes NaN because the style is auto, not 0px like you're expecting. Consider trying this instead:
var transitionTest = parseInt("0"+currentMargin,10);
This will trim off the "px" for you, as well as handle the case where the margin is a keyword.
I used setinterval to slide number of divs every period of time and that worked fine but the problem happend when i made function"getdata()" that testing this animation and returns the width,left postion,text inside Div for each p...please help me to improve the function "getdata()" to get these information about each p which it changes per sec or i value.
ineed to view data like that
1,left is:0,width:60
2,left is:34,width:40
3,left is:66,width:70
I want to make the data_text which is "1 or 2 or 3" is fixed while the width & data_p_l changes for each data_text "u can consider it it's an ID for the element" 4Ex "
1,left is:0,width:60
1>> this is fixed and this line won't be repeated
left is:20>> changing
width:20>> changing
Ihopt that i've cleared my question.
Thanks alot.
The HTML:
<div id="test"></div>
<div id="center">
<p id="th">3</p>
<p id="s">2</p>
<p id="f">1</p>
</div>
The jQuery:
$(document).ready(function(){
var i = null;
var width = $('#center').width();
var timer = setInterval(function() {
$('p').each(function() {
$(this).css({'left': $(this).position().left + i});
});
getdata('p' ,'#test');
i+=1;
},500);
function getdata(parentdiv,showdiv){
$(parentdiv).each(function(){
var $this = $(this);
var width = $this.width();
var data_p_l= $this.position().left;
var data_text= $this.text();
var dataset = data_text + ",Left value is: "+ data_p_l + ",
width value is: "+ width ;//+ ",id value is: "+ data_id;
$(showdiv).text($(showdiv).text() + ' ' + dataset);
});}
});
I'm not exactly sure what you are trying to do, but This might help. First in this section:
function getdata(parentdiv,showdiv){
$(parentdiv).each(function(){
var len = $( parentdiv ).length;
var width = $(e).width();
var data_p_l= $(e).position().left;
var data_text= $(e).text();
var dataset = data_text + ",Left value is: "+ data_p_l + ",width value is: "+ width;
$(showdiv).text(dataset);
});
}
You want to replace e with this.
function getdata(parentdiv,showdiv){
$(parentdiv).each(function(){
var len = $( parentdiv ).length;
var width = $(this).width();
var data_p_l= $(this).position().left;
var data_text= $(this).text();
var dataset = data_text + ",Left value is: "+ data_p_l + ",width value is: "+ width;
$(showdiv).text($(showdiv).text() + ' ' + dataset);
});
}
Inside the each function, this is used to refer to each element that gets iterated over. At the end of your function, you are putting your results into your div with id test. However, this is running in a loop, so you will only end up with output for the last p tag, and not each one. What I think you want to do is add to the test div like this: $(showdiv).text($(showdiv).text() + ' ' + dataset);
if you are experienced with relations between javascript and doctype declaration , any help would be appreciated. i use wordpress and i am trying to include cursor script into a page. the script works without default wordpress doctype, with it - it does not. any suggestions how to make the cursor script work, please?
HTML doctype declaration for my WordPress:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
Code for cursor:
<STYLE type="text/css">
<!--
.kisser {
position:absolute;
top:0;
left:0;
visibility:hidden;
}
-->
</STYLE>
<SCRIPT language="JavaScript1.2" type="text/JavaScript">
<!-- cloak
//Kissing trail
//Visit http://www.rainbow.arch.scriptmania.com for this script
kisserCount = 15 //maximum number of images on screen at one time
curKisser = 0 //the last image DIV to be displayed (used for timer)
kissDelay = 1200 //duration images stay on screen (in milliseconds)
kissSpacer = 30 //distance to move mouse b4 next heart appears
theimage = "cur.png" //the 1st image to be displayed
theimage2 = "small_heart.gif" //the 2nd image to be displayed
//Browser checking and syntax variables
var docLayers = (document.layers) ? true:false;
var docId = (document.getElementById) ? true:false;
var docAll = (document.all) ? true:false;
var docbitK = (docLayers) ? "document.layers['":(docId) ? "document.getElementById('":(docAll) ? "document.all['":"document."
var docbitendK = (docLayers) ? "']":(docId) ? "')":(docAll) ? "']":""
var stylebitK = (docLayers) ? "":".style"
var showbitK = (docLayers) ? "show":"visible"
var hidebitK = (docLayers) ? "hide":"hidden"
var ns6=document.getElementById&&!document.all
//Variables used in script
var posX, posY, lastX, lastY, kisserCount, curKisser, kissDelay, kissSpacer, theimage
lastX = 0
lastY = 0
//Collection of functions to get mouse position and place the images
function doKisser(e) {
posX = getMouseXPos(e)
posY = getMouseYPos(e)
if (posX>(lastX+kissSpacer)||posX<(lastX-kissSpacer)||posY>(lastY+kissSpacer)||posY<(lastY-kissSpacer)) {
showKisser(posX,posY)
lastX = posX
lastY = posY
}
}
// Get the horizontal position of the mouse
function getMouseXPos(e) {
if (document.layers||ns6) {
return parseInt(e.pageX+10)
} else {
return (parseInt(event.clientX+10) + parseInt(document.body.scrollLeft))
}
}
// Get the vartical position of the mouse
function getMouseYPos(e) {
if (document.layers||ns6) {
return parseInt(e.pageY)
} else {
return (parseInt(event.clientY) + parseInt(document.body.scrollTop))
}
}
//Place the image and start timer so that it disappears after a period of time
function showKisser(x,y) {
var processedx=ns6? Math.min(x,window.innerWidth-75) : docAll? Math.min(x,document.body.clientWidth-55) : x
if (curKisser >= kisserCount) {curKisser = 0}
eval(docbitK + "kisser" + curKisser + docbitendK + stylebitK + ".left = " + processedx)
eval(docbitK + "kisser" + curKisser + docbitendK + stylebitK + ".top = " + y)
eval(docbitK + "kisser" + curKisser + docbitendK + stylebitK + ".visibility = '" + showbitK + "'")
if (eval("typeof(kissDelay" + curKisser + ")")=="number") {
eval("clearTimeout(kissDelay" + curKisser + ")")
}
eval("kissDelay" + curKisser + " = setTimeout('hideKisser(" + curKisser + ")',kissDelay)")
curKisser += 1
}
//Make the image disappear
function hideKisser(knum) {
eval(docbitK + "kisser" + knum + docbitendK + stylebitK + ".visibility = '" + hidebitK + "'")
}
function kissbegin(){
//Let the browser know when the mouse moves
if (docLayers) {
document.captureEvents(Event.MOUSEMOVE)
document.onMouseMove = doKisser
} else {
document.onmousemove = doKisser
}
}
window.onload=kissbegin
// decloak -->
</SCRIPT>
<!--Simply copy and paste just before </BODY> section of your page.-->
<SCRIPT language="JavaScript" type="text/JavaScript">
<!-- cloak
// Add all DIV's of hearts
if (document.all||document.getElementById||document.layers){
for (k=0;k<kisserCount;k=k+2) {
document.write('<div id="kisser' + k + '" class="kisser"><img src="' + theimage + '" alt="" border="0"></div>\n')
document.write('<div id="kisser' + (k+1) + '" class="kisser"><img src="' + theimage2 + '" alt="" border="0"></div>\n')
}
}
// decloak -->
</SCRIPT>
The script is riddled with very old browser detection code, this could cause it to break in 'newer' browsers with a stricter DOCTYPE.
Try to remove the 'language="JavaScript1.2"' in the script tag. If that doesn't work you'd have to rewrite the browser detection.
The actual script isn't very complicated though so perhaps you could find parts elsewhere and combine them.
You need to do two things:
Hide the cursor (which is done with CSS)
Fetch the mouse position and place your own cursor there (typically an image). For this you will need a script that fetch the mouse position.
Shouldn't be too hard :)