Develop Reference

How do I make iframes responsive without using div?

I learnt from this post (Making an iframe responsive) that make an iframe responsive by adding a container with a class around the iframe, for instance,
<div class="intrinsic-container">
<iframe width="560" height="315" src="https://www.youtube.com/embed/I4YoBuJCbfo" frameborder="0" allowfullscreen></iframe>
</div>
Is there possible to embed <iframe>...</iframe> directly in my posts (without using <div>...</div>)? And I tried these solutions, but all of them don't work.
PS: I use two columns layout in WordPress. The ratio of video can be 16:9 (from YouTube), 4:3 (from Tencent), etc. Here is a temporary demo.

If you can use viewport units that is doable without an extra wrapper element.
Full page width:
iframe {
width: 100vw;
height: 56.25vw; /*16:9*/
}
<iframe width="560" height="315" src="https://www.youtube.com/embed/I4YoBuJCbfo" frameborder="0" allowfullscreen></iframe>
Half page width:
iframe {
width: 50vw;
height: 28.125vw; /*16:9*/
}
<iframe width="560" height="315" src="https://www.youtube.com/embed/I4YoBuJCbfo" frameborder="0" allowfullscreen></iframe>

The key here is the height and width ratio you want to keep. I took the liberty of using jQuery instead of javascript to do this. The code triggers upon clicking the button. It calculates the width and height ratio of the iframe and adapts both to your needs (in this case I assumed you wanted it to fill the containers width).
You'll probably want to loop through all videos if you have multiple on one page and run the code on window resizing and page-loading.
Here is the JSFiddle
Hope it helps :)
html
<iframe id="iframe" width="640" height="360" src="https://www.youtube.com/embed/4SDVkdcO8ts" frameborder="0" allowfullscreen></iframe>
<button id="button" style="float: left">Click me!</button>
jQuery
$(document).ready(function(){
$("button").click(function(){
var ratio = $("#iframe").height() / $("#iframe").width();
$("#iframe").width("100%");
var newWidth = $("#iframe").width();
$("#iframe").width(newWidth);
$("#iframe").height(newWidth*ratio);
$("button").text("resize the window and click me again!");
});
});

Use bootstrap class to make iframe responsive.
<div class="embed-responsive embed-responsive-16by9">
<iframe class="embed-responsive-item" allowfullscreen
src="//www.youtube.com/embed/zpOULjyy-n8?rel=0" >
</iframe>
</div>

disable video autoplay in twitter bootrap and stop video when modal is closed

I'm embedding a local video to my page using Bootstrap 3
I use this code inside the modal
<div class="embed-responsive embed-responsive-16by9">
<iframe class="embed-responsive-item" height="300" width="480"
src="hunnybunny.mp4"></iframe></div>
How can I prevent this video from autoplay? I also want the video to stop when the modal window is closed.

I was having issues with this and found a workaround. Drop the iframe in the html, for example:
(Note: I wanted video on the left so i put it in a row in the first 7 columns, also the "class = left_vid" is defined in my "override" custom linked style sheet)
<div class="row">
<div class="col-md-7">
<video controls class= left_vid> <source src="vid.mp4" type="video/mp4">
This browser does not display this video type </video>
</div>
<div class="col-md-5">
<p> Text stuff </p>
</div>
</div>
In the style.css
.left_vid {
display:block;
margin-left:auto;
margin-right:auto;
width: 80%;
height:auto;
}

Is it necessary to use an iframe for this? If not have look at the HTML5 video-tag:
http://www.w3schools.com/html/html5_video.asp
You are using iframe, you can not stop playing, you can only remove element like this
$('#myModal').on('hidden.bs.modal', function () {
$( ".embed-responsive-16" ).remove();
})
This is just example, we dont have all you code :(

Youtube video shows on click of image

I've looked at a few implementations of this and so far none have worked so I'm resorting to posting. The concept is: a placeholder image which once clicked changes into the video and autoplays.
Current HTML:
<div id="ytvideo" style="display:none;">
<iframe width="939" height="528" id="ytvideo" frameborder="0" allowfullscreen></iframe>
</div>
<img class="aligncenter size-full" id="homevideo" alt="placeholder" src="/wp-content/uploads/2013/10/placeholder.jpg" width="940" height="548" />
Current JS:
jQuery(document).on('click','#homevideo',function(e){
jQuery('#ytvideo').show();
jQuery('#homevideo').hide();
jQuery('#ytvideo').attr("src","www.youtube.com/embed/[myvidid]?autoplay=1");
jQuery("#ytvideo").attr('src', jQuery("#ytvideo", parent).attr('src') + '?autoplay=1');
});
I've looked at trying to reload the iframe but that doesn't seem to work.
Any ideas?
MARKED: FIXED

You forgot the protocol - www.youtube.com/… would link to folder on the server.
With protocol it works fine – I’d suggest creating the whole iframe dynamically though, because with an empty src attribute at the beginning it would load the same page it is embedded in.
<div id="ytvideo" style="display:none;"></div>
<!-- replaced your image with a span here for fiddle -->
<span id="homevideo" data-vidid="mbOEknbi4gQ">click me</span>
$(document).on('click','#homevideo',function(e){
$('#homevideo').hide();
$('#ytvideo').html('<iframe width="939" height="528" id="ytvideo" frameborder="0" allowfullscreen src="http://www.youtube.com/embed/'+$(this).attr("data-vidid")+'?autoplay=1"></iframe>').show();
});
http://jsfiddle.net/HuVqm/

As discussed in one of the comments, you can get both the img and the video from the api.
This would be good if you didn't want to maintain the image, just wanted it to pull through from YouTube. (However I am not sure that YT provide an image as large as 939 so in your case you might still want to use your own image). I have put in a random channel name 'RIDEChannel' feel free to change that with your channel name.
<div id="vid"></div>
$.getJSON("http://gdata.youtube.com/feeds/api/users/RIDEChannel/uploads?max-results=1&v=2.1&alt=jsonc&callback=?", function (myvid) {
var vid = $("#vid");
$.each(myvid.data.items, function (i, item) {
vid.append("<img width='300' height='250' src='" + item.thumbnail.hqDefault + "'>");
$(document).on("click", "#vid img", function (event) {
vid.append("<iframe width='300' height='250' src='http://www.youtube.com/embed/" + item.id + "?autoplay=1' frameborder='0'></iframe>");
$(this).hide();
});
});
});

So the problem laid with the youtube url missing the http:// prefix and also for the fact that the iframe name was the same as the div it was enclosed in. (How silly of me) Thus it was attaching the SRC to the div, not the iframe.

Working DEMO
Try this,
First you cannot have same id for more than one elements <div id="ytvideo" and <iframe id="ytvideo"
[myvidid] in http://www.youtube.com/embed/[myvidid]?autoplay=1 should be replaced with the id of the video
html
<div id="ytvideo1" style="display:none;">
<iframe width="939" height="528" id="ytvideo" frameborder="0" allowfullscreen></iframe>
</div>
<img class="aligncenter size-full" id="homevideo" alt="placeholder" src="http://thefabweb.com/wp-content/uploads/2012/12/6191814472_fa47c79b67_b-900x600.jpg" width="940" height="548" data-vid='DBNYwxDZ_pA'/>
code
jQuery(document).on('click','#homevideo',function(e){
jQuery('#ytvideo1').show();
jQuery('#homevideo').hide();
jQuery('#ytvideo').attr("src","http://www.youtube.com/embed/"+$(this).data('vid')+"?autoplay=1");
});

If you have more than 1 video, it could be useful to store the url to the video in the html and use a class instead of an id.
Also, if you put the preview image into the background, behind the video, it will stay there until the iframe has loaded, reducing that "flickering" effect when clicked.
I also restructured the markup a bit to reduce redundancy, here I specify the size of the video and the video id only once.
Also, you should use jQuery's .one('click') instead of .click(), since you want that event listener removed after it has fired the first time.
html:
<div class="ytvideo"
data-video="73sgatbknvo"
style="width:939px; height:528px; background-image:url(http://lorempixel.com/939/528/)">
<div class="seo">
Have a meaningful description of the video here
</div>
</div>
CSS:
.ytvideo {
background-position: center;
background-size: contain;
background-repeat: no-repeat;
cursor: pointer;
}
.ytvideo iframe {
border-style: none;
height: 100%;
width: 100%;
}
.ytvideo .seo {
display: none;
}
jQuery:
$('.ytvideo[data-video]').one('click', function() {
$(this).html('<iframe allowfullscreen src="//www.youtube.com/embed/'+$(this).data("video")+'?autoplay=1"></iframe>');
});
If you want to support browsers with no script support, you'd have to add a "noscript" element in the .ytvideo div that already contains the iframe.
fiddle:
http://jsfiddle.net/6ARc7/

Dropdown form navigation on the same page as another form

I'm looking to create a dropdown menu on our website that will appear on all pages in our navigation and is used to navigate to a set of particular brand pages. This is what I'm using:
<form>
<select name="URL" onchange="window.location.href=this.form.URL.options[this.form.URL.selectedIndex].value" style="font-weight: normal; width: 170px;">
<option value="">Select a brand...</option>
<option value="brand-a.html">A</option>
<option value="brand-b.html">B</option>
</select>
</form>
It works great, however there is a conflict between it and the other form(s) that may show up on the same page of our site (ie., shopping cart page, billing/shipping info). For example, you fill in your billing info, click submit, and an error comes up from our shopping cart - I'm guessing because the brand form above doesn't have an option selected, and it's trying to submit that first.
Is there any way to have both forms on the page?
Please let me know if I can provide any additional details to help resolve this issue.
Thanks!

Simply remove the form encapsulating the select tag. In HTML5 this is valid.

You can use frame to show more than one form in the same page. In the below code, I have shown 3 forms.
<frameset frameborder="0" border="0" bordercolor="#FBE134" framespacing="0" rows="125,*" frameborder = "0" framespacing = "0" border = "0">
<frame frameborder="0" noresize scrolling="no" name="framTop" src="header.php" frameborder="0" marginwidth="0" marginheight="0">
<frameset frameborder="0" cols="170,*">
<frame frameborder="0" name="framLeft" noresize scrolling="no" src="" frameborder="0" marginwidth="0" marginheight="0">
<frame frameborder="0" marginwidth="1" marginheight="1" noresize name="framRight" src="">

Changing IFRAME height dynamically

How is it possible to fix the height issue of Google Trend charts dynamically.
For an example take a look on the output of following code.
<iframe width="600" height="320" src="http://www.google.com/trends/fetchComponent?hl=en-US&q=css-showcase&content=1&cid=TIMESERIES_GRAPH_0&export=5&w=600&h=320" style="border: none;"></iframe>
<hr>
first contents
<hr>
<iframe width="600" height="320" src="http://www.google.com/trends/fetchComponent?hl=en-US&q=html5&content=1&cid=TIMESERIES_GRAPH_0&export=5&w=600&h=320" style="border: none;"></iframe>
<hr>
second contents
on jsFiddle: http://jsfiddle.net/yzw8Y/

i didn't test it, but this could work.
function autoResize(id)
{
var newheight;
newheight=document.getElementById(id).contentWindow.document.body.scrollHeight;
document.getElementById(id).height=newheight + "px";
}
<iframe id="frame1" onload="autoResize('frame1')" ... >

set id for iframe
and in jquery set height
$('#idval').css('height','800px');