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javascript adding click events to buttons in a loop

The code below gets info from xml file.
I succesfully presents the id and name of each planet with a button.
I want to add an onclick event on the button.
Problem now is: it does add the onclick event but only on the last button created in the loop.
What am i doing wrong? Why doesnt it create a onclick event for each button, but only for the last one in loop?
function updatePlaneten() {
var valDiv, planets, valButton, textNode;
// Get xml files
planets = this.responseXML.getElementsByTagName("planeet");
// loop through the <planet> tags
for (var i = 0; i < planets.length; i++) {
valDiv = ''; // clear valDiv each time loop starts
// Get the id and the name from the xml info in current <planet> tag
valDiv += planets[i].getElementsByTagName("id")[0].childNodes[0].nodeValue + "<br>";
valDiv += planets[i].getElementsByTagName("name")[0].childNodes[0].nodeValue + "<br>";
document.getElementById("planetenID").innerHTML += valDiv + "<br>";
// Create button with a value and pass in this object for later reference use (valButton.object=this)
valButton = document.createElement("input");
// valButton.setAttribute("planeetID", planets[i].getElementsByTagName("id")[0].childNodes[0].nodeValue);
valButton.setAttribute("value", 'Meer info');
valButton.setAttribute("type", 'button');
valButton.id = (i + 1);
valButton.object = this;
//
// Here is the problem i cant get fixed
//
//valButton.onclick = function(){ showinfo(); }
valButton.addEventListener('click', showinfo);
// Place the button on screen
document.getElementById("planetenID").appendChild(valButton);
}
}
// simple function to check if it works
function showinfo() {
console.log(this.object);
console.log(this.id);
}

The trouble is this line:
document.getElementById("planetenID").innerHTML += valDiv + "<br>";
When you set innerHTML the content currently in there gets destroyed and replaced with the new html, meaning all your old buttons are now destroyed and new ones are created. The previously attached event listeners do not get attached to the new buttons.
Instead simply create a div/span or whatever container would best help, add your planet text or whatever to it and then use appendChild
valDiv = document.createElement("div");
var id = planets[i].getElementsByTagName("id")[0].childNodes[0].nodeValue;
var name = planets[i].getElementsByTagName("name")[0].childNodes[0].nodeValue;
valDiv.innerHTML = id+"<br>"+name+"<br>";
document.getElementById("planetenID").appendChild(valDiv);
You could also use insertAdjacentHTML
var id = planets[i].getElementsByTagName("id")[0].childNodes[0].nodeValue;
var name = planets[i].getElementsByTagName("name")[0].childNodes[0].nodeValue;
valDiv = id+"<br>"+name+"<br>";
document.getElementById("planetenID").insertAdjacentHTML("beforeend",valDiv);

function updatePlaneten() {
var valDiv, planets, valButton, textNode;
// Get xml files
planets = this.responseXML.getElementsByTagName("planeet");
// loop through the <planet> tags
for (var i = 0; i < planets.length; i++) {
(function(num){
valDiv = document.createElement("div");
// Get the id and the name from the xml info in current <planet> tag
var id = planets[num].getElementsByTagName("id")[0].childNodes[0].nodeValue + "<br>";
var name = planets[num].getElementsByTagName("name")[0].childNodes[0].nodeValue + "<br>";
valDiv.innerHTML = id+"<br>"+name+"<br>";
document.getElementById("planetenID").appendChild(valDiv);
// Create button with a value and pass in this object for later reference use (valButton.object=this)
valButton = document.createElement("input");
// valButton.setAttribute("planeetID", planets[i].getElementsByTagName("id")[0].childNodes[0].nodeValue);
valButton.setAttribute("value", 'Meer info');
valButton.setAttribute("type", 'button');
valButton.id = (num + 1);
valButton.object = this;
// FIX: PASS showinfo TO AN ANONYMOUS FUNCTION CONTAINING THE OBJECT
valButton.addEventListener('click', function(){
showinfo(valButton);
});
// Place the button on screen
document.getElementById("planetenID").appendChild(valButton);
}(i));
}
}
// simple function to check if it works
function showinfo(valButton) {
console.log(valButton.object);
console.log(valButton.id);
}

Change existing DIV from a CLASS to an ID

Is this possible? Or is there a way to tack on and ID to an existing div?
This is my code. I can't get the code to work using classes, but I found when I used getElementById and changed the div to an ID, that it did. But I have a ton of already posted stuff so it would take forever to go through all those posts and change it manually to an ID.
Can I incorperate JQuery in this and still have it work? I tried that with something I stumbled across but it didn't work so I removed it. I don't remember what it is now though. :S
<div id="imdb" class="imdb">tt2382396</div>
<script>
function imdbdiv() {
var imdbmain = "http://www.imdb.com/title/";
var end = "/#overview-top";
var idnum = document.getElementsByClassName("imdb");
var newdiv = document.createElement("div");
var done = "<a href='" + imdbmain + idnum + end + "'>IMDB</a>";
newdiv.innerHTML = done;
document.body.appendChild(newdiv);
}
window.onload = imdbdiv();
</script>
Can anyone help. I cannot for the life of me figure this out.
JsFiddle

Your problem was, you were appending the collection returned by document.getElementsByClassName instead of looping through the elements in the collection. You can verify this by looking at the href property of the link in your jsFiddle. You must loop through the values, then access the data in their innerHTML property.
You can use document.querySelectorAll to get a list of all elements matching a certain CSS selector, in your case .imdb. This is more flexible, in case you want to select elements with more than one class. I've pasted the code from the updated jsFiddle below.
function imdbdiv() {
var imdbMain = "http://www.imdb.com/title/",
end = "/#overview-top",
imdbValueDivs = document.querySelectorAll('.imdb'),
length = imdbValueDivs.length,
// Iterator values
i,
newDiv,
newLink;
// Loop over all of your link value containers
for (i = 0; i < length; i++) {
// Create the container
newDiv = document.createElement('div');
// Create the new link
newLink = document.createElement('a');
newLink.href = imdbMain + imdbValueDivs[i].innerHTML + end;
newLink.innerHTML = "My favorite film";
// Add the link to the container,
// and add the container to the body
newDiv.appendChild(newLink);
document.body.appendChild(newDiv);
}
}
window.onload = imdbdiv();

If you have many such divs on your page, then it could be like this:
<div class="imdb">tt2382396</div>
<div class="imdb">tt2382396</div>
<div class="imdb">tt2382396</div>
<script>
function imdbdiv() {
var imdbmain = "http://www.imdb.com/title/";
var end = "/#overview-top";
var idnums = document.getElementsByClassName("imdb");
for (var i =0; i < idnums.length; i++) {
var newdiv = document.createElement("div");
var done = "<a href='" + imdbmain + idnums[i].innerText + end + "'>IMDB</a>";
newdiv.innerHTML = done;
document.body.appendChild(newdiv);
}
}
window.onload = imdbdiv();
</script>
See jsfiddle
UPDATE:
The following string was incorrect:
window.onload = imdbdiv;

Okay, so your question is a little bit unclear.
The way I understood your question is that you have a whole bunch of div elements with class attribute and what you want is to simply copy the class value to the id attribute of the div elements.
If that's correct then try something like this with jquery:
<script>
$(document).ready(function(){
$(".imdb").each(function(imdbDiv){
var classValue = imdbDiv.attr("class");
imdbDiv.attr("id", classValue);
});
});
</script>

HTML elements created by the content script are not accessible by the content script

Within content script I use on.Message.addListener to add images with a class name to the currently active web page.
chrome.extension.onMessage.addListener(function (message, sender, sendResponse) {
// Selecting HTML tags
var divs = document.getElementsByTagName("div");
// Creating a full URL to use icon1
var imageUrl = chrome.extension.getURL("icons/icon1.png");
// Function to create an image
function PlaceImage(source_x, source_y, imageUrl) {
var newImage = document.createElement("img");
newImage.src = imageUrl;
newImage.style.position = "absolute";
newImage.style.left = source_x + 'px';
newImage.style.top = source_y + 'px';
// Assigning a class name
newImage.className = "label-key";
// Add an element to the HTML document
document.body.appendChild(newImage);
}
// Divs
for(var j=0; j<divs.length; j++) {
// Get the position of an element with getBoundingClientRect
var position = divs[j].getBoundingClientRect();
var x = position.left;
var y = position.top;
y -=32;
// Create comment image
PlaceImage(x, y, imageUrl);
}
});
Later I try to write to console by clicking on one of just created images by:
$(".label-key").click(function () {
console.log("hello");
});
There is no reaction of the browser.
I tried to write to console by accessing some class element with a different name, which was part of the original web page(received from the server). It worked fine.
More over I created another element within content script, but this time outside of onMessage.AddListener:
var newDiv = document.createElement("div");
document.body.appendChild(newDiv);
newDiv.style.width = "100px";
newDiv.style.height = "100px";
newDiv.style.backgroundColor = "red";
newDiv.className = "label-key";
It also worked fine. jQuery was able to access this element.
Therefore, I think there is something wrong with html elements created by the onMessage.addListener part of content script.
For additional reference: when I right-click on the newly created element "Inspect element" - I can see that the element is part of the html document. However, if I click "View page source" the element is not there.

Well, you are creating a new element of the class label-key, but the click handler assignment does not automagically extend to newly-created elements.
$(".label-key").click(...) is not behaving like a CSS rule despite looking like one: it collects all elements that match at the time of invocation and binds a listener for them.
So, if you add more images later, you need to add a click handler again:
function PlaceImage(source_x, source_y, imageUrl) {
var newImage = document.createElement("img");
newImage.src = imageUrl;
newImage.style.position = "absolute";
newImage.style.left = source_x + 'px';
newImage.style.top = source_y + 'px';
// Assigning a class name
newImage.className = "label-key";
newImage.click(function () {
console.log("hello");
});
// Add an element to the HTML document
document.body.appendChild(newImage);
}

Dynamically add and remove style based on JavaScript variable

I'm dynamically generating a div using JavaScript. When mouse is over certain elements in the page the new div appears. On mouseout it disappears. All that is working fine. But I want the div to be top-positioned according to the element the mouse was over of. So I record the position of the element with getBoundingClientReach:
function lopen(AbstId) { //called OnMouseOver
var rect = document.getElementById(AbstId).getBoundingClientRect();
var st3="px";
divtop = rect.top+st3 ;
alert ("Hello :" + divtop); //for checking purposes only
if (this.element == null) {
this.element = document.createElement('div');
this.element.id = "myPopup";
this.element.className = "myPopupBody";
this.element.onmouseover = 'prevent()'; //if mouse over new div, do not close
this.element.style["top"] = divtop; //HERE IS MY PROBLEM
}
document.body.appendChild(this.element);
popUpDetails();
}
function lclose () { //called OnMouseOut
document.getElementById("myPopup").innerHTML = " ";
document.body.removeChild(this.element);
}
The piece of code
this.element.style["top"] = divtop;
is getting the correct top value on first event, but do not actualize for further onmouseover events, even though divtop is actually refreshing (I check with the alert of 5th line).
Does anyone spot the problem?

Again, just for completeness. The problem was an incorrect assignment of style: top. Below the right code
function lopen(AbstId) { //called OnMouseOver
var rect = document.getElementById(AbstId).getBoundingClientRect();
var st3="px";
divtop = rect.top+st3 ;
//alert ("Hello :" + divtop); //for checking purposes only
if (this.element == null) {
this.element = document.createElement('div');
this.element.id = "myPopup";
this.element.className = "myPopupBody";
this.element.onmouseover = 'prevent()'; //if mouse over new div, do not close
//this.element.style["top"] = divtop; //here WAS my problem -deleted line
}
document.body.appendChild(this.element);
document.getElementById("myPopup").style["top"] = divtop; //here right code
popUpDetails();
}

Variables within function is null

I have the following function:
function slideDown() {
//get the element to slide
sliding = document.getElementById('slideDiv1');
//add 1px to the height each time
sliding.style.height = parseInt(sliding.style.height)+1+'px';
t = setTimeout(slideDown,30);
if (sliding.style.height == "401px") {
clearTimeout(t);
}
}
which is called within this function:
function addDiv(nextImageSlide) {
//finds the src attribute of the image nested in the Li
elemChild = nextImageSlide.firstChild;
imageSrc = elemChild.getAttribute('src');
//loops and creates six divs which will be the slices. adds background property etc
for (i = 0, j = 0, k = 1; i< = 19; i++, j++, k++) {
var newDiv = document.createElement('div');
newDiv.setAttribute('class', 'new-div');
newDiv.id='slideDiv' + k;
newDiv.style.height = '1px';
newDiv.style.background = 'url(' + imageSrc +') scroll no-repeat - '+39.5 * j + 'px 0';
var a = document.getElementById('content');
a.appendChild(newDiv);
}
slideDown();
}
Which is called within another function that defines nextImageSlide. It later removes all the divs that it just made.
The idea is for an image gallery. When the user hits the next button, I want slices of the next image to slide down to show the next image. Those slices are then taken away and the new image revealed.
I would like something like this: http://workshop.rs/projects/jqfancytransitions/.
It's for an assignment so we have to write all the code ourself and this is the best way I can think to replicate it. The only problem is that I keep getting an error:
'sliding is null. sliding.style.height = parseInt(sliding.style.height)+1+'px';'
No matter what I do I can't get rid of it. The thing is if I define sliding as a totally different id, (for example I made a random little div outside of everything), it working.
This error shows when I try to access the divs, it just made that it throws a hissy fit.
Anyone see any errors in my code?

Hopefully this is just a typo while pasting into the site here, but:
car a = document.getElementById('content');
^---syntax error, which'll kill your entire script - var?