Develop Reference

Trying to focus on a specific div on click of an anchor link

I am trying to get focus on a specific div on click of an anchor link.
Here is the code
Link
I am facing a problem that the view is rendered from different partial views like header footer etc.
The header contains the link to a particular div from another view and it has a sticky navbar. When I click the link on nav bar it does focus on the div. But some part of div hides behind the header navbar.
Which looks clumsy according to the UI perspective.
Here is the navbar code:
<nav><li>Link</li></nav>
The example code for page div could be something like
<div id="divname">Some Content</div>
Please give me a clue how can I get the div to show just beneath the sticky menu bar.

Try with giving some margin-top to the div you want to focus on clicking, so that, the navbar will not hide your div and then change your href from
href="somepage.html#divname"
to
href="#divname"
only. Always give unique ids or classes to the elements in HTML so that the machine will not get confused between them and treat two different elements the same way. Hope this will work for you. If not post a response for help.

There's plenty of questions like this one on StackOverflow. Try this one for example:
https://stackoverflow.com/a/59380086/1973005
You can add a pseudo-element (::before) to the linked element in CSS, using the following settings. This creates an invisible block above the linked element which again creates an offset for the linked element position, since the top of that pseudo-element will actually be the position of the link anchor.
.anchor_offset::before {
display: block;
content: ' ';
height: 10em; // Whatever height your navbar is
margin-top: -10em; // Whatever height your navbar is
width: 100%;
visibility: hidden;
}
<div id="divname" class="anchor_offset">Some Content</div>

How long does it take until click event is triggered?

I try to make a select box whose entries are opened after clicking into the input box. After selecting one of the items, the dropdown should be closed again.
I want to achieve the open/close part of the dropdown without the use of javascript.
The html looks like this:
<div id="outer">
<input type="text" id="input">
<div id="results">
<div>Test 1 </div>
<div>Test 2 </div>
<div>Test 3 </div>
<div>Test 4 </div>
</div>
</div>
<div id="label">
</div>
After clicking onto an item, the selected value should appear below the #outer div (just for demonstration purposes).
The Javascript for assigning click events to the dropdown values:
document.querySelectorAll("#results div").forEach(setClick);
function setClick(node) {
node.addEventListener("click", setText.bind(null, node.innerHTML))
}
function setText(t) {
document.getElementById("label").innerHTML = t;
}
Now I will show you my first draft of css code:
#outer {
width: 200px;
position: relative;
}
#input {
width: 100%;
}
#results {
position: absolute;
width: 100%;
display: block;
visibility: hidden;
background-color: white;
}
#results > div:hover {
background-color: lightblue;
cursor: pointer;
}
#outer:focus-within #results, #results:hover {
visibility: visible;
}
This works like a charm but fails in one point:
After clicking an item, the dropdown is not closed. This is because of the #results:hover selector which is needed to keep the dropdown open after clicking onto an item. The click takes the focus out of the input field, thus the focus-within selector is not applied anymore. As the focus is removed from the input before the click occurs, the dropdown is hidden when the final click arrives in the document (this is my understanding of the problem).
Thus I use the hover selector which forces the div to keep open as long as the mouse is above the div.
You can test this here:
https://jsfiddle.net/hcetz1og/3/
My solution for this was a transition that hides the dropdown after the focus has been taken away:
#outer:not(:focus-within) #results:hover {
visibility: hidden;
transition-property: visibility;
/*use 10 ms and the clicked value in the drop down won't be shown */
transition-delay: 100ms;
transition-timing-function: step-end;
}
This works on my machine when I use 100ms as a delay. If I use 10ms, I have the same problem again. It seems that the click event is triggered "very" late.
Feel free to test it here:
https://jsfiddle.net/hcetz1og/2
Question:
How long will it take until the click event arrives at the document? Is there a fixed time span I have to wait or can the delay depend on every machine?
If so, I am forced to not use plain CSS but must use javascript for this I think.
Edit:
Feel free to post an alternative solution using plain css. But please be aware that I mainly want to focus on getting an answer to this question, not alternative solutions.

As #Mark Baijens said in the comments, using timeouts is a bad practice, so here is a pretty clean solution.
I used JavaScript to render the dropdown, not the CSS, because the CSS is where Your issue is coming from.
I don't know why would You want to set the innerHTML, but not some other property, like style.visibility for example. It just doesn't make sense to me, so with that in mind, let's get our hands on this :)
Working demo >> HERE <<.
Step 1 - remove the #outer...:hover parts of CSS
So, You are left with this:
#outer {
width: 200px;
position: relative;
}
#input {
width: 100%;
}
#results {
position: absolute;
width: 100%;
display: block;
visibility: hidden;
background-color: white;
}
#results > div:hover {
background-color: lightblue;
cursor: pointer;
}
Step 2 - add the onfocus event to the input field
Just assign a function call to the onfocus attribute of the input. Everything else in the HTML stays the same.
<div id="outer">
<input type="text" id="input" onfocus="showElements()">
<div id="results">
<div>Test 1 </div>
<div>Test 2 </div>
<div>Test 3 </div>
<div>Test 4 </div>
</div>
</div>
<div id="label">
</div>
Step 3 - create the showElements and hideElements function:
function showElements() {
document.getElementById("results").style.visibility = 'visible';
}
function hideElements() {
document.getElementById("results").style.visibility = 'hidden';
}
Step 4 - call the hideElements() when clicked outside the input element
There are two cases for the click outside the input element:
Case 1 - we clicked on one of the divs inside the #results wrapper
Case 2 - clicking outside the input field, but not on one of the divs inside the #results wrapper
In the first case, we will modify the assignment of the onclick handler like this:
document.querySelectorAll("#results div").forEach(setClick);
function setClick(node) {
node.addEventListener("click", setTextAndHideElements.bind(null, node.innerHTML));
}
So, the setText function now becomes setTextAndHideElements and looks like this:
function setTextAndHideElements(t) {
document.getElementById("label").innerHTML = t;
hideElements();
}
For the second case (clicking outside the input field, but not on one of the divs inside the #results wrapper), we must watch for the click on the whole page (document element), and respond to the action like this:
document.onclick = function(e) {
if (e.target.id !== 'input'){
hideElements();
}
}
Note: this will override any previously assigned onclick events assigned to the document element.
As mentioned in the beginning, working demo is >> HERE (codepen.io) <<.

I tried another solution which requires no setting of additional JS events.
See: https://jsfiddle.net/hcetz1og/4/
I gave every result item a tabindex of "0" to ensure, those items can be focusable.
Then i removed the #outer:not() part from the css and replaced the hover selector with this: #results:focus-within. Additional I called node.blur() on the node after clicking onto them.
Summary:
Change in HTML:
<div tabindex="0">Test 1 </div>
Change in JS:
function setText(t, node) {
document.getElementById("label").innerHTML = t;
node.blur();
}
Change in CSS:
#outer:focus-within #results, #results:focus-within {
visibility: visible;
}
What do you think about this one? Should be stable I think because the focus onto the #results div is set before the click event is triggered onto the result item.
Event order should be (based on my observation):
input focus -> input blur -> item focus -> item click
Not sure if the step between blur and focus can lead to a visible problem. Theoretically, the results div must be hidden and shown again in a very small amount of time.
But I investigated this with chrome's performance timeline and did not recognize a new render between both events. One can see, that the result item is focused (outline is set onto it) and then it disappears as expected.

How to add a button in any expected place by using appendChild() function in JavaScript?

I want to add a button in my web page when a certain event is occurred by using javaScript. I searched online much and try to solve this problem by using appendChild() function.
My code is like this :
var btn = document.createElement(‘button’);
btn.body.appendChild(btn);
Here I am facing two problems
My button is added but in a certain corner of my html page and
I can’t add style to this new created button without providing css to other buttons.
So how can I add this button in a certain positon and add css to this button
Thanks in advance.

Your first problem is you added the button after body. So that your button is appeared in a certain corner of your html page.
To solve this problem you may add this after an id containing div. And this div must be in your expected location.
Make a div which id is myButton in your expected location
id="addButton"
Then append your button after this id like this
document.getElementById("addButton").appendChild(newButton);
To provide CSS to this new created button your CSS code will be like this
#addButton button {
display: block;
background: green;
padding: 10px;
color: #ffffff;
}
To provide the hover effect your code will be
#addButton button:hover {
background: red;
}

Append it to the document instead of a button..
var btn = document.createElement('button');
btn.innerText="button";
btn.style.background="red";
document.body.appendChild(btn);

How to open a small box from a web page to make a choice

So I am really new with javascript, html, and css and am currently in the process of creating a game web application. I would like to be able to have kind of a pop up box when you click on a card the appears in the middle of the screen showing the options that you can click for that card (meanwhile the main page colors get darker) and when you select one of those options it goes away (Or if you click off of the popup).
I'm not sure if I'm explaining it very well, but I don't even know what to look up online because I don't know what that is called or even where to start with that. Any ideas?

Make a div in your html and a :
<div id="test"></div>
<div id="card"></div>
give the diff a background color using rgba to enable transparency and the default display value set to none and give it 100% width and height:
#test {
width: 100%;
height: 100%;
display: none;
background-color: rgba(255,255,255,0.6);
}
Then in javascript u can use an event listener on click to trigger change the display state to block:
document.getElementById("card").addEventListener("click", function() {
document.getElementById("test").style.display = "block";
});
Here is a jsfiddle so you can check it out: click

jQuery hide() targeting <p> element hides background of entire parent div

I have a simple blog page - a list of posts that each consist of a title and contents. When the page loads I want all posts' contents hidden until their titles are clicked. The following code accomplishes this but with an unwanted side effect - the on-page-load hide() function that hides each post's content also hides the background of the containing (id="content") div:
Relevant JavaScripts:
$(document).ready(function() {
$(".blog_post p").hide();
//BLOG CONTENT ANIMATION
$('.blog_post').click(function() {
$(this).find('p').slideToggle(130);
});
});
Summary of blog page:
<section class="grid_7">
<div id="content">
<div class="blog_post">
<div class="blog_head">
<h2>Title</h2>
</div>
<p>Contents</p>
</div>
</div>
</section>
Relevant CSS:
section {
border: 1px solid white;
}
#content {
margin: 20px;
background-image:url('../images/content_background.jpg');
}
When the page loads the list of titles displays without the #content parent div's background. However when I click on a post's title the #content div's background shows up behind all posts up to and including that one.
Any idea what's going on?

It sound like you have some CSS that applies to the blog_head elements, that makes them float, for example:
.blog_post { float: left; }
In that case, the reason that the background doesn't show up is that the height of the content div is zero. A floating element doesn't affect the size of its parent, and when the content div only contains the headers, the height becomes zero. The background is still there, but there is no area where it's visible.
Add an overflow to the content div, that will make it contain its children:
#content { overflow: hidden; }
Note that this will not hide anything as long as you don't specify a size for the content element, it will just change how it's rendered so that it will become a container for its children.

A bit of a stab in the dark: Your #content div will, of course, be a lot shorter as the blog posts aren't there, basically consisting just of the divs with the titles. Perhaps that's the problem.
Does the image have a blank (or subtle) bit at the top or something, so that it's only apparent that it's there when there's more content in the #content div (e.g., when it's taller)? Or is there some other reason you can see that when #content is really short, you wouldn't see the background on the part of it that's there? (You can use the debugging tools in most modern browsers to see what the dimensions of the #content div are when the paragraphs are hidden; or slap a border on it temporarily, but tools these days are pretty good.)
Basically, since the jQuery doesn't, of course, actually hide the background, it must be a side-effect of the paragraphs being hidden — because of the effect that has on the dimensions of the #content div.

This is working fine for me:
HTML:
<div class="blog_post">
<div class="blog_head">
<h2>Title</h2>
</div>
<p>Contents</p>
</div>
</div>
CSS:
section {
border: 1px solid white;
}
#content {
margin: 20px;
background-image:url('http://bluebackground.com/__oneclick_uploads/2008/04/blue_background_03.jpg');
}
JS
$(document).ready(function() {
$(".blog_post p").hide();
//BLOG CONTENT ANIMATION
$('.blog_post').click(function() {
$(this).find('p').slideToggle(130);
});
});
Check it live here: Jsfiddle example