I am making a web chat. I have a div called chatbody. I want the div to scroll to bottom using javascript so that the last message is displayed. However, the code that I am using scrolls it to top instead. Here is the code:
<script type="text/javascript">
function chatbody() {
var myDiv = document.getElementByClassName('chatbody');
myDiv.innerHTML = variableLongText;
myDiv.scrollTop = 0;
}
</script>
Kindly assist to solve my issue.
Try This
var myDiv = document.getElementByClassName('chatbody')[0];
function scrollToBottom(nameOfBlock) {
nameOfBlock.scrollTop = nameOfBlock.scrollHeight
}
U can pass your variable as an argument
Related
I'm working on a flexible menu, that does not need to jump from page to page when clicking 'links'.
The JavaScript I use for that is as follows:
var inbox = document.getElementById("u-content-inbox");
var friends = document.getElementById("u-content-friends");
var agenda = document.getElementById("u-content-agenda");
var list = document.getElementById("u-content-list");
var news = document.getElementById("u-content-news");
var notes = document.getElementById("u-content-notes");
function Inbox() {
inbox.style.visibility='visible';
}
function Friends() {
friends.style.visibility='visible';
}
function Agenda() {
agenda.style.visibility='visible';
}
function List() {
list.style.visibility='visible';
}
function News() {
news.style.visibility='visible';
}
function Notes() {
notes.style.visibility='visible';
}
The div elements are like this:
<div id="u-content-inbox" style="visibility:hidden;">
Inbox
</div>
<div id="u-content-friends" style="visibility:hidden;">
Friends
</div>
Each div has a "u-content-x".
However, when I try to change the style attribute "visibility" to visible. It gives me the following error: Uncaught TypeError: Cannot read property 'style' of null
I'm not seeing what I'm doing wrong. Could somebody please bring clearance to me why exactly JavaScript, or rather, I fail to make it work?
Whenever I run a check on
if(!inbox) {
alert("Inbox div has not been found);
}
does not show the alert message.
Make sure you call your javascript after the document is loaded! I'm nearly certain you are trying to get element references before they exist in the dom. The best practices is to put all scripts just before the closing of the body tag.
<script src="some/path/to/file.js"></script>
</body>
If your scripts appear in the document before the elements do, you can put your code inside of this load event function:
window.addEventListener('load', function() {
//your code here
});
Just as a note on your code architecture, you could attach a class to each element and then do this:
var toMakeVisible = document.getElementsByClassName('some-class');
for (var i=0; i<toMakeVisible; ++i) {
var elem = toMakeVisible[i];
elem.style.visibility = 'visible';
}
I'm making a live chat website for my users. I'm fetching the chat messages via ajax.
Whenever I enter a new message, it does get added to the database and is displayed, but the scroll doesn't go to the bottom of the results.
Here's the example :-
When I type in a new message. The scroll doesn't go to the bottom.
When I manually scroll, then I get all the messages.
Here's my HTML div in which data is fetched via ajax.
<div id="chat">
</div>
I tried this, but it didn't work.
window.setInterval(function(){
var elem = document.getElementById('chat');
elem.scrollTop = elem.scrollHeight;
}, 1000);
What would be the best way to get my result ?
I did a little more than was asked for, but here's my answer. Please note that I did not include the AJAX function, and instead used the first message as a template, and just inserted that over and over to simulate new messages from AJAX. You would replace the line $('#msg-template').clone()... with your AJAX function, and the completion function that runs after AJAX should contain the next line: if(autoScroll){ ScrollChat(); }.
The fiddle has comments too (and some HTML and CSS): http://jsfiddle.net/mmwu1920/
var autoScroll = true;
function ScrollChat(){
$('#chat').scrollTop($('#chat')[0].scrollHeight).trigger('scroll');
}
function RefreshMessages(){
$('#msg-template').clone().appendTo('#chat');
if(autoScroll){ ScrollChat(); }
}
setInterval(RefreshMessages, 1000);
ScrollChat();
$('#chat').on('scroll', function(){
if($(this).scrollTop() < this.scrollHeight - $(this).height()){
autoScroll = false;
}
else{
autoScroll = true;
}
});
Set the scroll position on the parent element (or the element that has the scrollbar):
<div id="container">
<div id="chat">
</div>
</div>
-
window.setInterval(function(){
var elem = document.getElementById('container');
elem.scrollTop = elem.scrollHeight;
}, 1000);
please refer to JSFiddle link: https://jsfiddle.net/s11oo2gg/.
We are not allowed to use jQuery and iframe here.
The problem right now if you click on resistor first and hover over different content images then come back out by clicking the X mark, the content image would get stucked where you left off and would not load the the other content images properly. It would show a broken image link.
I like to reload only the <div id="slider1_contain"> everytime I click on <span class="closeButton">(X mark) so the target content images can be loaded accordingly.
I dont not want to have location.reload(); to resolve this when the X is click. I dont want to reload the whole page but only the div.
I saw people were asking the same question and solve it with AJAX. Do I need AJAX for this case? Or is there something we can do in the following javascript?
Thank you in advance!!
<script type="text/javascript">
function showContent(target){
document.getElementById(target).style.display = 'block';
document.getElementById("boxThumb").style.display = 'none';
}
function hideContent(target){
document.getElementById(target).style.display = 'none';
document.getElementById("boxThumb").style.display = 'block'
}
</script>
<script type="text/javascript">
var children = document.querySelectorAll('.toggle > section[id]');
function showDetailContent(target) {
// Simply loop over our children and ensure they are hidden:
for (var i = 0, child; child = children[i]; i++) {
child.style.display = 'none';
}
// Now, show our child we want to show
document.getElementById(target).style.display = 'block';
}
</script>
If you want to reload just the div, you can use innerHTML.
document.getElementById(target).innerHTML = '<img src="image.jpg">';
I'm currently making an iphone webapp and have almost finished it, I just need to fix this one little issue im having
Ive managed to hide one div layer and show another, but what I would like is for the same button to then show the layer I have hid and hide the one that I have shown when clicked again. So basically clicking the button would take it back to the original state
the code I am currently using is
<script type="text/javascript">
function toggle_layout(d)
{
var onediv = document.getElementById(d);
var divs=['Posts','Posts2'];
for (var i=0;i<divs.length;i++)
{
if (onediv != document.getElementById(divs[i]))
{
document.getElementById(divs[i]).style.display='none';
}
}
onediv.style.display = 'block';
}
</script>
It hides a div I have named "Posts" and shows a div I have named "Posts2", but clicking it again does not reverse the effect.
If you wanna take a look at my site its http://a-m-creativecapture.tumblr.com/
Will have to view it on a mobile to see what I am talking about.
Have you tried style.visibility (visible|hidden) instead of style.display?
Assuming that your divs are something like this:
<div id="posts"></div>
<div id="posts2"></div>
You can use the following code:
var posts = document.getElementById('posts'),
posts2 = document.getElementById('posts2');
function toggle() {
if (this == posts) {
posts.style.display = 'none';
posts2.style.display = 'block';
} else {
posts.style.display = 'block';
posts2.style.display = 'none';
}
}
div1.onclick = toggle;
div2.onclick = toggle;
How can you detect clicks on javascript which is fired from a <DIV>?
For example I have 3 adSense ads in 3 different <DIV>s on a page, and I want to detect and trigger an operation when an ad is clicked.
It is easy to detect clicks on<DIV> when it is empty, or with any other element; but how to detect clicks on adSense ad (code)?
As far as I'm aware, Adsense ads are loaded in an iframe element so accessing them would be violating the same origin policy. This means you can't detect clicks in an iframe pointing to an external URL, so it can't be done.
are you using any frameworks like jQuery? if so, you could add a click handler to a child of a div:
targetElement = $("#yourDivId").children()[0]
$(targetElement).click(function(){
alert("target element was clicked");
});
If I would really need to achieve something like this, I would cheat a bit with the user.
Instead of trying to get click on iframe, make an overlay div and place it above iframe. Attach click event to it, and when div is clicked, hide it.
It will give the user feeling that he clicked on link, but it did not worked correctly. The second time he clicks it will already worked, cause overlay is hidden.
An example code (just for explanation purpose):
<html>
<style>
.test {
position : absolute;
top : 0;
left : 0;
width : 300;
height : 300;
z-index : 999;
filter : alpha(opacity = 0);
opacity : 0;
background-color:black;
}
</style>
<script>
function start(){
var div = document.getElementById("target");
var source = document.createElement("div");
source.className = "test";
document.body.appendChild(source);
var style = source.style;
var div2 = document.createElement("div");
document.body.appendChild(div2);
source.onclick = function(e){
style.display = "none";
div.onmouseout = function(){
div2.innerHTML = "mouseout";
style.display = "";
div.onmouseout = null;
}
div2.innerHTML = "clicked";
}
}
</script>
<body onload="start()">
<div id="target">
<iframe src="http://mail.ru" style="width:300;height:300"></iframe>
</div>
</div>
</html>