I have some CSS:
fieldset {
border-radius: 5px;
border: 3px solid blue;
padding: 5px;
margin: 0em;
}
legend {
font-weight: bold;
color: green;
}
#myform{
width: 330px;
margin: 0em;
}
body {
font-family: Arial, sans-serif;
}
When I embed it with <style>, it works perfectly fine:
But when I put the same CSS into a stylesheet and import it using <link>, I get some random whitespace:
I have removed the form elements completely, and there is still whitespace (although if I keep them in, there is considerably more of it). I used the Chrome developers console to check form and body height using $(body).css("height") (and the same for the form), and it gives me a number which is way too small to include the whitespace, but seems to match the height if the whitespace is ignored. Where is this coming from?
This seems to be a bug, when changing the margin of the body back and forth in the developers console it gets right again. Setting this property in the CSS doesn't have any effect at all.
A measly workaround would be creating a javascript file for your popup, like popup.js, and then change the margin in there after the popup window is loaded:
document.addEventListener('DOMContentLoaded', function() {
document.body.style.margin = '8px';
});
I took 8px as value because that's the standard value of a Chrome popup:
You should consider reporting this bug to the Chrome issues list.
put CSS with !important keyword
i.e.
#myform{
width: 330px !important;
margin: 0em !important;
}
Related
I wrote a Google Chrome extension, which popups a dialog with an autocomplete field and it's own style, but there are some sites where my CSS gets totally broken, which doesn't look very nice.
I know about isolating styles with iFrames, but in Google Chrome extension there is no way to isolate my HTML and CSS in this way. Another method is to wrap all my stuff into a separated div with it's own id and relative styles for that id, and I do so, but it seems that it doesn't work on some sites with "hard" tags style overloading or "!important" directives in the CSS code.
So, I want to know is there any way to really isolate my styles in z convenient way or it's my bad carma to overload every little CSS property to fix one or another style issue for each site?
By the way: I set up my manifest to load all the things at the "document_end", but I see it's not being applied to the stylesheets which is every time loaded whenever the DOM is ready.
At the time of asking the question, your only option was to either use iframes, or stylesheets with a very high specificity and explicitly set all properties that might affect styles. The last method is very cumbersome, because there will always be some property that is overlooked by you. Consequently, the only usable method for isolating stylesheets was to use iframes.
The solution to this problem -isolation of styles without iframes- is Shadow DOM (since Chrome 25). You can find a tutorial at HTML5 Rocks. For a real-world Chrome extension that uses Shadow DOM to isolate styles, see Display #Anchors (source code here).
As I've recently gone through the gauntlet of this issue, I want to share some information I think is valuable.
First, Rob W's answer is correct. Shadow DOM is the correct solution to this problem. However, in my case not only did I need CSS isolation, I also needed JavaScript events. For example, what happens if the user clicks a button that lives within the isolated HTML? This gets really ugly with just Shadow DOM, but we have another Web Components technology, Custom Elements, to the rescue. Except that as of this writing there is a bug in chrome that prevents custom element in chrome extensions. See my questions here and here and the bug here.
So where does that leave us? I believe the best solution today is IFrames, which is what I went with. The article shahalpk linked is great but it only describes part of the process. Here's how I did it:
First, create an html file and js file for your isolated widget. Everything inside these files will run in an isolated environment in an iframe. Be sure to source your js file from the html file.
//iframe.js
var button = document.querySelector('.my-button');
button.addEventListener('click', function() {
// do useful things
});
//iframe.html
<style>
/* css */
</style>
<button class='my-button'>Hi there</button>
<script src='iframe.js'></script>
Next, inside your content script create an iframe element in javascript. You need to do it in javascript because you have to use chrome.extension.getURL in order to grab your iframe html file:
var iframe = document.createElement('iframe');
iframe.src = chrome.extension.getURL("iframe.html");
document.body.appendChild(iframe);
And that's it.
One thing to keep in mind: If you need to communicated between the iframe and the rest of the content script, you need to chrome.runtime.sendMessage() to the background page, and then chrome.tabs.sendMessage from the background page back to the tab. They can't communicate directly.
EDIT: I wrote a blog post detailing everything I learned through my process, including a complete example chrome extension and lots of links to different information:
https://apitman.com/3/#chrome-extension-content-script-stylesheet-isolation
In case my blog goes down, here's the sources to the original post:
Blog post
Example source
Either use all
.some-selector {
all: initial;
}
.some-selector * {
all: unset;
}
or use Shadow DOM
Library
function Widget(nodeName, appendTo){
this.outer = document.createElement(nodeName || 'DIV');
this.outer.className = 'extension-widget-' + chrome.runtime.id;
this.inner = this.outer.createShadowRoot();
(appendTo || document.body).appendChild(this.outer);
}
Widget.prototype.show = function(){
this.outer.style.display = 'block';
return this;
};
Widget.prototype.hide = function(){
this.outer.style.display = 'none';
return this;
};
Usage
var myWidget = new Widget();
myWidget.inner.innerHTML = '<h1>myWidget</h1>';
You can access the widget contents via myWidget.inner and the outer via myWidget.outer.
Styles
/*
* Reset Widget Wrapper Element
*/
.extension-widget-__MSG_##extension_id__ {
background: none;
border: none;
bottom: auto;
box-shadow: none;
color: black;
cursor: auto;
display: inline;
float: none;
font-family : "Helvetica Neue", "Helvetica", "Arial", sans-serif;
font-size: inherit;
font-style: normal;
font-variant: normal;
font-weight: normal;
height: auto;
left: auto;
letter-spacing: 0;
line-height: 100%;
margin: 0;
max-height: none;
max-width: none;
min-height: 0;
min-width: 0;
opacity: 1;
padding: 0;
position: static;
right: auto;
text-align: left;
text-decoration: none;
text-indent: 0;
text-shadow: none;
text-transform: none;
top: auto;
vertical-align: baseline;
white-space: normal;
width: auto;
z-index: 2147483648;
}
/*
* Add your own styles here
* but always prefix them with:
*
* .extension-widget-__MSG_##extension_id__
*
*/
.extension-widget-__MSG_##extension_id__{
position: fixed;
top: 100px;
margin: 0 auto;
left: 0;
right: 0;
width: 500px;
}
.extension-widget-__MSG_##extension_id__::shadow h1 {
display: block;
margin: 0 auto;
padding: 20px;
background-color: yellow;
border: 10px solid green;
font-size: 20px;
text-align: center;
}
I recently created Boundary, a CSS+JS library to solve problems just like this. Boundary creates elements that are completely separate from the existing webpage's CSS.
Take creating a dialog for example. After installing Boundary, you can do this in your content script
var dialog = Boundary.createBox("yourDialogID", "yourDialogClassName");
Boundary.loadBoxCSS("#yourDialogID", "style-for-elems-in-dialog.css");
Boundary.appendToBox(
"#yourDialogID",
"<button id='submit_button'>submit</button>"
);
Boundary.find("#submit_button").click(function() {
// some js after button is clicked.
});
Elements within #yourDialogID will not be affected by the existing webpage. And find() function returns a regular jQuery DOM element so you can do whatever you want with it.
Hope this helps. Please let me know if you have any question.
https://github.com/liviavinci/Boundary
Use iframes. It's a workaround, but works fine.
Maxime has written an article on it.
I wrote a Google Chrome extension, which popups a dialog with an autocomplete field and it's own style, but there are some sites where my CSS gets totally broken, which doesn't look very nice.
I know about isolating styles with iFrames, but in Google Chrome extension there is no way to isolate my HTML and CSS in this way. Another method is to wrap all my stuff into a separated div with it's own id and relative styles for that id, and I do so, but it seems that it doesn't work on some sites with "hard" tags style overloading or "!important" directives in the CSS code.
So, I want to know is there any way to really isolate my styles in z convenient way or it's my bad carma to overload every little CSS property to fix one or another style issue for each site?
By the way: I set up my manifest to load all the things at the "document_end", but I see it's not being applied to the stylesheets which is every time loaded whenever the DOM is ready.
At the time of asking the question, your only option was to either use iframes, or stylesheets with a very high specificity and explicitly set all properties that might affect styles. The last method is very cumbersome, because there will always be some property that is overlooked by you. Consequently, the only usable method for isolating stylesheets was to use iframes.
The solution to this problem -isolation of styles without iframes- is Shadow DOM (since Chrome 25). You can find a tutorial at HTML5 Rocks. For a real-world Chrome extension that uses Shadow DOM to isolate styles, see Display #Anchors (source code here).
As I've recently gone through the gauntlet of this issue, I want to share some information I think is valuable.
First, Rob W's answer is correct. Shadow DOM is the correct solution to this problem. However, in my case not only did I need CSS isolation, I also needed JavaScript events. For example, what happens if the user clicks a button that lives within the isolated HTML? This gets really ugly with just Shadow DOM, but we have another Web Components technology, Custom Elements, to the rescue. Except that as of this writing there is a bug in chrome that prevents custom element in chrome extensions. See my questions here and here and the bug here.
So where does that leave us? I believe the best solution today is IFrames, which is what I went with. The article shahalpk linked is great but it only describes part of the process. Here's how I did it:
First, create an html file and js file for your isolated widget. Everything inside these files will run in an isolated environment in an iframe. Be sure to source your js file from the html file.
//iframe.js
var button = document.querySelector('.my-button');
button.addEventListener('click', function() {
// do useful things
});
//iframe.html
<style>
/* css */
</style>
<button class='my-button'>Hi there</button>
<script src='iframe.js'></script>
Next, inside your content script create an iframe element in javascript. You need to do it in javascript because you have to use chrome.extension.getURL in order to grab your iframe html file:
var iframe = document.createElement('iframe');
iframe.src = chrome.extension.getURL("iframe.html");
document.body.appendChild(iframe);
And that's it.
One thing to keep in mind: If you need to communicated between the iframe and the rest of the content script, you need to chrome.runtime.sendMessage() to the background page, and then chrome.tabs.sendMessage from the background page back to the tab. They can't communicate directly.
EDIT: I wrote a blog post detailing everything I learned through my process, including a complete example chrome extension and lots of links to different information:
https://apitman.com/3/#chrome-extension-content-script-stylesheet-isolation
In case my blog goes down, here's the sources to the original post:
Blog post
Example source
Either use all
.some-selector {
all: initial;
}
.some-selector * {
all: unset;
}
or use Shadow DOM
Library
function Widget(nodeName, appendTo){
this.outer = document.createElement(nodeName || 'DIV');
this.outer.className = 'extension-widget-' + chrome.runtime.id;
this.inner = this.outer.createShadowRoot();
(appendTo || document.body).appendChild(this.outer);
}
Widget.prototype.show = function(){
this.outer.style.display = 'block';
return this;
};
Widget.prototype.hide = function(){
this.outer.style.display = 'none';
return this;
};
Usage
var myWidget = new Widget();
myWidget.inner.innerHTML = '<h1>myWidget</h1>';
You can access the widget contents via myWidget.inner and the outer via myWidget.outer.
Styles
/*
* Reset Widget Wrapper Element
*/
.extension-widget-__MSG_##extension_id__ {
background: none;
border: none;
bottom: auto;
box-shadow: none;
color: black;
cursor: auto;
display: inline;
float: none;
font-family : "Helvetica Neue", "Helvetica", "Arial", sans-serif;
font-size: inherit;
font-style: normal;
font-variant: normal;
font-weight: normal;
height: auto;
left: auto;
letter-spacing: 0;
line-height: 100%;
margin: 0;
max-height: none;
max-width: none;
min-height: 0;
min-width: 0;
opacity: 1;
padding: 0;
position: static;
right: auto;
text-align: left;
text-decoration: none;
text-indent: 0;
text-shadow: none;
text-transform: none;
top: auto;
vertical-align: baseline;
white-space: normal;
width: auto;
z-index: 2147483648;
}
/*
* Add your own styles here
* but always prefix them with:
*
* .extension-widget-__MSG_##extension_id__
*
*/
.extension-widget-__MSG_##extension_id__{
position: fixed;
top: 100px;
margin: 0 auto;
left: 0;
right: 0;
width: 500px;
}
.extension-widget-__MSG_##extension_id__::shadow h1 {
display: block;
margin: 0 auto;
padding: 20px;
background-color: yellow;
border: 10px solid green;
font-size: 20px;
text-align: center;
}
I recently created Boundary, a CSS+JS library to solve problems just like this. Boundary creates elements that are completely separate from the existing webpage's CSS.
Take creating a dialog for example. After installing Boundary, you can do this in your content script
var dialog = Boundary.createBox("yourDialogID", "yourDialogClassName");
Boundary.loadBoxCSS("#yourDialogID", "style-for-elems-in-dialog.css");
Boundary.appendToBox(
"#yourDialogID",
"<button id='submit_button'>submit</button>"
);
Boundary.find("#submit_button").click(function() {
// some js after button is clicked.
});
Elements within #yourDialogID will not be affected by the existing webpage. And find() function returns a regular jQuery DOM element so you can do whatever you want with it.
Hope this helps. Please let me know if you have any question.
https://github.com/liviavinci/Boundary
Use iframes. It's a workaround, but works fine.
Maxime has written an article on it.
I'm working on a project to upgrade a system to use the button tag rather than regular submit buttons. For the formatting of the buttons, I have the following CSS classes:
button::-moz-focus-inner {
border: none; /* overrides extra padding in Firefox */
}
button {
background: transparent url('images/greenrightbutton.png') no-repeat scroll top right;
color: #FFFFFF;
display: block;
font: normal 12px arial, sans-serif;
height: 25px;
padding-right: 8px; /* sliding doors padding */
padding-top: 0px;
padding-bottom: 0px;
padding-left: 0px;
margin: 0px;
text-decoration: none;
border: 0px;
overflow: visible;
}
#loginbox button {
float: right;
}
button span {
background: transparent url('images/greenleftbutton.png') no-repeat top left;
display: block;
line-height: 18px;
padding: 4px 5px 5px 12px;
margin: 0px;
border: 0px;
}
They work absolutely perfectly in every browser except IE8.
In IE8, the buttons work in most places, but then I find a page where the two background images don't quite line up and no amount of tweaking padding, line spacing etc fixes it.
Does anyone know why this might be the case?
Demo page: http://test6.placement.co.uk/demo/test.asp
---Update---
After some fairly extensive testing and trying things, I've now got a pretty fair idea of what's causing the problem in page 1, but no idea how to fix it, while another page with the same issue has a completely different cause (which I haven't found) but where I HAVE stumbled on a fix...
The problem on the first page appears to relate to a ul entered further up the page. Take that out and everything behaves - unfortunately, that's not an option as the ul is part of user-entered content, so I'm scratching my head about that. Particularly given...
Page 2 has no uls to cause an issue, but randomly sticking two break tags in just before my button code resolves the problem.
Naturally, THAT fix doesn't work on page 1.
I'm just about ready to give in and find some alternative way of rendering these buttons, because whatever the actual problem is, it's clearly so deep in either my CSS or my basic HTML that I'm probably never going to find it.
I don't see any difference between IE8 and other browser. Could you pleas mention bit more clear what you want to do?
I am using a condensed font in Cufon. When the page loads, my menu is too wide and wraps. Then Cufon replaces the font and it looks fine. To reduce the visual distraction, I want to set the font size smaller and then have Cufon change the font size when it displays.
Currently the font size is set by the div containing the menu. Here is the CSS for the menu container:
.header_menu_block
{
display: block;
margin: 0px 0px 0px 0px;
padding: 0px 0px 0px 0px;
margin-top: 3px;
/*margin-left: 238px; ie 6 can't handle, see margin block below*/
float: left;
text-align: left;
font-weight: normal;
font-size: 14px;
color: #FFFFFF;
height: 41px;
width: 991px;
}
The Cufon replacement code looks like this:
<script type="text/javascript">
Cufon.replace('.header_menu_block_col_menu ',
{ color: '#ffffff',
hover: {color: '#204966'}
} );
</script>
I've tried setting the CSS font size to 12px and then using the following Cufon code, but it does not work:
<script type="text/javascript">
Cufon.replace('.header_menu_block_col_menu ',
{ color: '#ffffff',
hover: {color: '#204966'},
font-size:'14px'
} );
</script>
Does anyone know how to do this?
You could try using the set() method. I find that this works.
<script type="text/javascript">
Cufon.set('fontSize', '14px').replace('.header_menu_block_col_menu ',
{ color: '#ffffff',
hover: {color: '#204966'}
} );
</script>
Although the manual explicitly suggests not using the font size.
https://github.com/sorccu/cufon/wiki/API
Let me guess, you never see the underlying font in non-IE browsers, right? The non-cufon appears briefly first in IE? I've been dealing with the same issue and I solved it by having the div with the text fade into view with jQuery. The fade time can be set to appear very fast--200ms in this example, I think you can make it fade-in even faster.
$(window).load(function(){$(".header_menu_block_col_menu").fadeIn(200);});
Don't forget to set the CSS for that div to display:none for the fade-in to work...
Of course, if your viewer has Javascript disabled, then nothing will appear--but what percentage of visitors to your web site have js disabled?
And, worried about your Google ranking with display:none? Read more on Google Groups.
I did it changing my CSS as below
.cufon-active h1 { /* for Cufon.replace(‘h1′) */
font-size: 3em;
color: #FF0000;
}
I am having some trouble with a font size with CSS. Below you see I have .post I have < pre > tags that are nested inside of the post class so should the css I have for the pre tags work below? It is not working but I can't figure out why? The text inside my pre tags end up being 15px instead of 12px
.post {
width: 100%;
clear: both;
padding: 10px 0;
border-bottom: #CBCBCB 1px solid;
background: url(images/post_element.gif) no-repeat 126px 21px;
font-family: arial;
font-size: 15px;
}
.post pre{
font-size: 12px;
}
http://monc.se/kitchen/38/cascading-order-and-inheritance-in-css
.post pre{
font-size: 12px !important;
}
Should work, but to answer your questing we need to view all html + css because it really depends...
In a vacuum, that code should work. However, base tag styling can vary browser-to-browser and <pre> tends to be a bit of an odd one. My first thought is that some other style is overriding it.
Have you used Firebug (or some other developer console) to take a look at the styles being applied and the computed style for the element? That should put you on the right track.
This was a weird issue, I had to end up changing the class and font size for all the other text, everything except the pre tags to get it to finally quit resizing after page load from my JS syntax highlighter