I have a page on my site where I'm displaying HTML email.
Some of that email seems to come with CSS that overrides my site layouts such that certain things get misplaced...
e.g. I have a toolbar at the top of the page that on some mails covers the various header information from the email.
Is there a way of creating a div where I can put the html email with a layout that effectively says 'Stay in this div and don't bugger about with anything else'?
Worth noting that I have the html content as 'text' rather than referring to an external website. (It's actually a return from an API, but assuming the same restrictions apply)
%iframe{srccode: #mail.html}
Just gives me a blank iframe
Include your mail using an IFrame similar to this:
<iframe src="http://www.w3schools.com"></iframe>
This will keep the styles separate
see http://www.w3schools.com/tags/tag_iframe.asp for options to customize the IFrame
If using html as text (rather than referencing an existing page:
%iframe{srcdoc: "#{#mail.html}"} #for rails / haml
or
<iframe srcdoc="<your html as text>"></iframe>
You may be able to incorporate the scoped style:
<div>
<style scoped>
h1 { color: FireBrick; }
p { color: SaddleBrown; }
</style>
<h1>This is an H1 in a scoped div. Regardless of global styles the text should be "FireBrick".</h1>
<p>This is a paragraph in a scoped div. The text should be "SaddleBrown".</p>
</div>
<p>This is another paragraph, that will unaffected by the scoped style and remain black.</p>
worth noting: this feature is still experimental and is not widely supported by 2015 browsers, currently, only FireFox v21.0+ supporting this feature. (more info # w3school.com)
Reference: https://css-tricks.com/saving-the-day-with-scoped-css/
Dave's answer above
<iframe src="http://www.w3schools.com"></iframe>
is good for referencing an external site, or a page that exists as html.
If using html as text (rather than referencing an existing page):
%iframe{srcdoc: "#{#mail.html}"} #for rails / haml
or
<iframe srcdoc="<your html as text>"></iframe>
And then formatting the iframe to suit does the trick.
Related
I need to be able to embed HTML snippets (nested elements and CSS) fetched from a remote api inside my document, in a way that their CSS won't affect on my whole document.
I need to fetch (random) gmail messages HTMLs and embed them in my website. The thing is that most messages have their CSS tags to style the message html. The problem is that some of these CSS mess up with my own document CSS. How can I embed an html snippet with CSS, in a way that it will have its own scope and not interact with what's outside of it?
<html>
<body>
<h1>Your gmail messages</h1>
<div id="gmail-message">
<!-- Here to be injected automatically. Changing classes, etc is not possible -->
<h1>This a gmail message</h1>
<style type="text/css">
h1 {
color: red;
}
</style>
</div>
</body>
</html>
The h1 tag outside the gmail-message div is also affected and is therefore red.
What do I need to do to get around this?
One solution would be to use an iframe.
Another solution would be to extract all css and html, then add an attribute (example: scope) to every html tag inside of gmail-messag.
Then modifiy the css and add an attribut selector.
Example:
<html>
<body>
<h1>Your gmail messages</h1>
<div id="gmail-message">
<!-- Here to be injected automatically. Changing classes, etc is not possible -->
<h1 scoped>This a gmail message</h1>
<style type="text/css">
h1[scoped] {
color: red;
}
</style>
</div>
</body>
</html>
But propably using an ifram is a more easy solution.
Easiest way is to use iframe / object / embed tag (tested on firefox).
If you can use Javascript and HTML5 you can also use shadow DOM or make custom element that uses slot tag (also in shadowRoot).
You might want to look into using The Shadow DOM
An important aspect of web components is encapsulation — being able to
keep the markup structure, style, and behavior hidden and separate
from other code on the page so that different parts do not clash, and
the code can be kept nice and clean. The Shadow DOM API is a key part
of this, providing a way to attach a hidden separated DOM to an
element.
However, be aware this is new tech and, as always, Microsoft browsers don't handle it.
I've found my solution.
First, insert an empty iframe tag somewhere.
<iframe id="iframeTag" src="about:blank"></iframe>
Second, load the html snippet into that iframe, the following way:
var doc = document.getElementById('iframeTag').contentWindow.document;
doc.open();
doc.write(<html_snippet>);
doc.close();
This way the <html_snippet>'s css won't mix up with the outer document's.
Use the srcdoc attribute on iframe to scope your HTML and CSS.
<iframe srcdoc="<p>Hello world!</p>"></iframe>
It's supported on all major browsers: https://caniuse.com/iframe-srcdoc
I am trying to figure out a way to display an archive of email newsletters on my client's site. The issue is that the newsletters are full of a zillion inline styles, which is great for seeing them in Outlook or wherever, but they're not looking too hot in an otherwise-nicely styled site.
My goal is for my client to be able to copy the entire source code of a generated newsletter (which her list management company* gives her access to) and paste it into the CMS (drupal, if it makes a difference).
*Constant Contact? Mail Chimp? I forget. One of those.
Then I'd like to display it on her site, inside the basic structure (header, nav, etc) of the rest of the site. If this was 1997, I'd say "iframes!" and be done with it, but A) that seems like a lame solution, and B) the code doesn't actually exist on a page by itself, which I think is required for iframes.
Is there some kind of tag I can put around this block of HTML to isolate it from the rest of the site's styles? Or is there another way to go about this entirely?
Thanks!
IFrames are the only way to go that I've ever been able to find. The only alternative to this would be to override every style in the parent page's CSS for the newsletter display area.
As you noted, using an iframe will probably require you to host the newsletters in an independent file. The only alternative to this that I'm aware of is that you can use JavaScript to dynamically create and/or populate the iframe.
If you go with this method, you could have the newsletter present in a div with a specific class, and then use JavaScript to move the div into an iframe. The big downside being that this wouldn't happen for users without JavaScript enabled.
9 years later and there still isn't a better solution.
If you don't have an external source (you can't add html into a frame manually) you need to use js to insert the messy html/css (in my case I use it to view emails)
<iframe class="my-frame" width="100%" height="100%" src="about:blank"></iframe>
and js:
const frame = document.querySelector('.my-frame');
frame.contentWindow.document.open('text/html', 'replace');
frame.contentWindow.document.write(hereGoesYourMessyHtmlCss);
frame.contentWindow.document.close();
Is there a reason why you can't use a modal? That would allow you to force a new request and make the page render how you'd want it to by not applying your general stylesheet while at the same time keeping your user on the desired page. Of course, it doesn't display the element inline so-to-speak, but it's nearly functionally equivelent.
Cutting and pasting raw HTML presents too many security problems, in my opinion. Never trust user's input. Even when the content is entirely benign, next week the designer of newsletter might decide to change their formatting or incorporate some javascript and you'll be responsible for anything that might go wrong.
Therefore I would implement a parser that would drop anything but the content part and leave only b, a, h*, blockquote and similar simple elements, like the ones allowed in forum posts, as well as their styles. After that, you can display it as a normal post in a CMS. I don't see any reason why that should look differently.
As for how to isolate that from your other CSS, you don't really need to if you are careful that all of CSS rules of your CMS apply to elements with specific classes. Alternatively, do a CSS reset for your posts:
.post p {
margin: 0;
...
.post /* all the standard CSS reset rules preceded with .post */
and then
<div class="post"> content parsed from your CMS </div>
Another option that I haven't used myself but am looking to possibly leverage in a similar situation is to use the Shadow DOM which is part of the Web Components spec. My main concern is that we still have some user's using IE 11 and while there seems to be support for polyfills it doesn't look like covering all browser's is real straight forward based on what I've read elsewhere.
Some details on how to use Shadow DOM to this effect can be found here and here. I've also created a small gist that I've created to demonstrate basic idea that I've been formulating as I learn about how the Shadow DOM works which I'll be updating as I learn more. Below you can see a snapshot of the content of that gist.
<!doctype html>
<html>
<head>
<style>
.row {
display: flex;
}
.column {
flex: 50%;
padding: 10px;
height: 300px;
}
* {
color: Red;
}
</style>
</head>
<body>
<div class="row">
<div class="column" style="background-color:#aaa;">
<h2>Column 1</h2>
<div id="content1">
SOME CONTENT FROM CMS
</div>
</div>
<div class="column" style="background-color:#bbb;">
<h2>Column 2</h2>
<div id="content2">
SOME MORE CONTENT FROM CMS
</div>
</div>
</div>
<script>
document
.getElementById("content1")
.attachShadow({ mode: 'open' })
.innerHTML = `
<style>
*{all:initial}
style{display: none}
div{display: block}
</style>
<h3>This text is not red</h3>
<div>slot content: <slot></slot></div>`;
document
.getElementById("content2")
.attachShadow({ mode: 'open' })
.innerHTML = `
<style>
*{all:initial}
style{display: none}
div{display: block}
</style>
<h3>This text is not red</h3>
<div>slot content: <slot></slot></div>`;
</script>
</body>
</html>
This sounds very backwards, but I want to take existing CSS classes and make them inline in the element itself (The css styles and the html elements are in the same file). There is a reason for this, for which I will not go into detail.
Example:
<html>
<style type="text/css">
.p1 { height: 10px; }
</style>
<body>
<p class="p1">...</p> <!-- Remove class="p1" and replace with style="height: 10px;" -->
<p class="p1">...</p>
<p class="p1">...</p>
</body>
</html>
Keep in mind there can be many CSS classes, and many can belong to a single element.
Edit: The reason I'm doing this is because (based on our client) we want to generate PDF documents from an HTML template. The PDF tool we use does not work well with external CSS classes.
You are looking for Premailer (The source available as well) - it is a Ruby library that does just that (inlines CSS for HTML email - but the output isn't specific to HTML email - it should work just fine with your PDF document generator as well).
There is also lamson.html.HtmlMail if you are using Python and there are a variety of Node.js libraries available to do the same thing.
MailChimp has a page for this in their labs, the CSS Inliner -
http://beaker.mailchimp.com/inline-css
It does leave the class, however.
I am having 1 pure html page for ex. sample.html. I need to include this html into another pure html for ex.Orginal.html.How to do this? I am having a header image in my sample.html.It should come at the top of the Orginal.html page.
If you're using Apache web server, you could try using server side includes.
You can't do such things in pure HTML, unless you use frames or iframe element. But better merge them by hand...
Here is an example of how to do it in pure HTML with an iframe, which although strangely not mentioned in HTML 4 specification is supported by all major browsers (and is in the HTML 5 specification)
<body>
<h1>This is original page</h1>
<p>Some content on original page.</p>
<iframe src="sample.html" width="600" height="300"></iframe>
</body>
You can adjust the width and height and you can also remove the border if you want the page to be more seamless.
Be wary of JavaScript solutions to this problem, especially if you want to be viewed on mobile devices.
Additional note: Avoid frameset solutions also, as they aren't valid markup.
See Include One File In Another, which has a summary of the various techniques that are available (along with their pros and cons).
You could use JavaScript to load some HTML from one document into another. This task is fairly simple using the jQuery toolkit:
$("The ID of a container (a div element for instance) in which you want to load
the contents of a HTML file").load("path to html file you want to load");
<div id="inserthere" />
$(function ()
{
$("#inserthere").load("loadme.html"); // Load the contents of loadme.html
// and stuff it in the div with the
// ID of "inserthere"
});
I am trying to figure out a way to display an archive of email newsletters on my client's site. The issue is that the newsletters are full of a zillion inline styles, which is great for seeing them in Outlook or wherever, but they're not looking too hot in an otherwise-nicely styled site.
My goal is for my client to be able to copy the entire source code of a generated newsletter (which her list management company* gives her access to) and paste it into the CMS (drupal, if it makes a difference).
*Constant Contact? Mail Chimp? I forget. One of those.
Then I'd like to display it on her site, inside the basic structure (header, nav, etc) of the rest of the site. If this was 1997, I'd say "iframes!" and be done with it, but A) that seems like a lame solution, and B) the code doesn't actually exist on a page by itself, which I think is required for iframes.
Is there some kind of tag I can put around this block of HTML to isolate it from the rest of the site's styles? Or is there another way to go about this entirely?
Thanks!
IFrames are the only way to go that I've ever been able to find. The only alternative to this would be to override every style in the parent page's CSS for the newsletter display area.
As you noted, using an iframe will probably require you to host the newsletters in an independent file. The only alternative to this that I'm aware of is that you can use JavaScript to dynamically create and/or populate the iframe.
If you go with this method, you could have the newsletter present in a div with a specific class, and then use JavaScript to move the div into an iframe. The big downside being that this wouldn't happen for users without JavaScript enabled.
9 years later and there still isn't a better solution.
If you don't have an external source (you can't add html into a frame manually) you need to use js to insert the messy html/css (in my case I use it to view emails)
<iframe class="my-frame" width="100%" height="100%" src="about:blank"></iframe>
and js:
const frame = document.querySelector('.my-frame');
frame.contentWindow.document.open('text/html', 'replace');
frame.contentWindow.document.write(hereGoesYourMessyHtmlCss);
frame.contentWindow.document.close();
Is there a reason why you can't use a modal? That would allow you to force a new request and make the page render how you'd want it to by not applying your general stylesheet while at the same time keeping your user on the desired page. Of course, it doesn't display the element inline so-to-speak, but it's nearly functionally equivelent.
Cutting and pasting raw HTML presents too many security problems, in my opinion. Never trust user's input. Even when the content is entirely benign, next week the designer of newsletter might decide to change their formatting or incorporate some javascript and you'll be responsible for anything that might go wrong.
Therefore I would implement a parser that would drop anything but the content part and leave only b, a, h*, blockquote and similar simple elements, like the ones allowed in forum posts, as well as their styles. After that, you can display it as a normal post in a CMS. I don't see any reason why that should look differently.
As for how to isolate that from your other CSS, you don't really need to if you are careful that all of CSS rules of your CMS apply to elements with specific classes. Alternatively, do a CSS reset for your posts:
.post p {
margin: 0;
...
.post /* all the standard CSS reset rules preceded with .post */
and then
<div class="post"> content parsed from your CMS </div>
Another option that I haven't used myself but am looking to possibly leverage in a similar situation is to use the Shadow DOM which is part of the Web Components spec. My main concern is that we still have some user's using IE 11 and while there seems to be support for polyfills it doesn't look like covering all browser's is real straight forward based on what I've read elsewhere.
Some details on how to use Shadow DOM to this effect can be found here and here. I've also created a small gist that I've created to demonstrate basic idea that I've been formulating as I learn about how the Shadow DOM works which I'll be updating as I learn more. Below you can see a snapshot of the content of that gist.
<!doctype html>
<html>
<head>
<style>
.row {
display: flex;
}
.column {
flex: 50%;
padding: 10px;
height: 300px;
}
* {
color: Red;
}
</style>
</head>
<body>
<div class="row">
<div class="column" style="background-color:#aaa;">
<h2>Column 1</h2>
<div id="content1">
SOME CONTENT FROM CMS
</div>
</div>
<div class="column" style="background-color:#bbb;">
<h2>Column 2</h2>
<div id="content2">
SOME MORE CONTENT FROM CMS
</div>
</div>
</div>
<script>
document
.getElementById("content1")
.attachShadow({ mode: 'open' })
.innerHTML = `
<style>
*{all:initial}
style{display: none}
div{display: block}
</style>
<h3>This text is not red</h3>
<div>slot content: <slot></slot></div>`;
document
.getElementById("content2")
.attachShadow({ mode: 'open' })
.innerHTML = `
<style>
*{all:initial}
style{display: none}
div{display: block}
</style>
<h3>This text is not red</h3>
<div>slot content: <slot></slot></div>`;
</script>
</body>
</html>