How to Force Browsers to Print Background Images in CSS

How can I force browsers to print background images in CSS?

You have very little control over a browser's printing methods. At most you can SUGGEST, but if the browser's print settings have "don't print background images", there's nothing you can do without rewriting your page to turn the background images into floating "foreground" images that happen to be behind other content.

How to get a background image to print using css?

It's up to the user and their browser settings to print or not print background images. To keep yourself from relying on that, put the images directly in the HTML with an actual <img /> tag.

How to forcefully print background image in HTML?

By default, a browser will ignore background css rules when printing a page, and you can't overcome this using css.

The user will need to change their browser settings.

Therefore, any image which you need to print should be rendered as an inline image rather than a css background. You can use css to display the inline image only for print though. Something like this.

HTML

<div class"graph-image graph-7">
  <img src="graph-7.jpg" alt="Graph Description" />
</div>

CSS

.graph-7{background: url(../img/graphs/graph-7.jpg) no-repeat;}
.graph-image img{display: none;}

@media print{
  .graph-image img{display:inline;}
}

Using this code, or similar code, means the image is used once in html and once in css.
The html version is hidden using css, and for print it displays as normal. This is a hack, but it will do what you want it to do. It will print the image.

Having said that, what you're doing is terribly bad practice. Nothing which conveys meaningful information to the user should be conveyed using css alone. Not only is it semantically incorrect, but it makes the graph less useful to users. An inline image is much better, and if you can, that's what you should use.

How can I print background images in FF or IE?

Have you considered using a print stylesheet? This could allow you to do something like:

<div class="star">*</div>

/* media:screen */
.star {
    background: ...;
    overflow: hidden;
    text-indent: 9999em;
}

/* media:print */
.star {
    text-indent: 0;
}

or even easier:

<div class="star"><img src="./images/star.jpg" alt="*" /></div>

/* media:screen */
.star img {
    visibility: hidden;
}

/* media:print */
.star img {
    visibility: visible;
}

You can specify stylesheets browsers should use by supplying a media tag, either by css or on the link element:

<link rel="stylesheet" type="text/css" href="main.css" media="screen" />
<link rel="print stylesheet" type="text/css" href="print.css" media="print" />

Background color not showing in print preview

The Chrome CSS property -webkit-print-color-adjust: exact; works appropriately.

However, making sure you have the correct CSS for printing can often be tricky. Several things can be done to avoid the difficulties you are having. First, separate all your print CSS from your screen CSS. This is done via the @media print and @media screen.

Often times just setting up some extra @media print CSS is not enough because you still have all your other CSS included when printing as well. In these cases you just need to be aware of CSS specificity as the print rules don't automatically win against non-print CSS rules.

In your case, the -webkit-print-color-adjust: exact is working. However, your background-color and color definitions are being beaten out by other CSS with higher specificity.

While I do not endorse using !important in nearly any circumstance, the following definitions work properly and expose the problem:

@media print {
    tr.vendorListHeading {
        background-color: #1a4567 !important;
        -webkit-print-color-adjust: exact; 
    }
}

@media print {
    .vendorListHeading th {
        color: white !important;
    }
}

Here is the fiddle (and embedded for ease of print previewing).

CSS @media print issues with background-color;

IF a user has "Print Background colours and images" turned off in their print settings, no CSS will override that, so always account for that. This is a default setting.

Once that is set so it will print background colours and images, what you have there will work.

It is found in different spots.
In IE9beta it's found in Print->Page Options under Paper options

In FireFox it's in Page Setup -> [Format & Options] Tab under Options.

Print background images and colors in IE without checking “Print background colors and images”

As noted on MDN

This feature is non-standard and is not on a standards track. Do not
use it on production sites facing the Web: it will not work for every
user. There may also be large incompatibilities between
implementations and the behavior may change in the future.

As such it should not be relied upon, indeed support in Chrome is marked as 'Buggy', all other browsers are not supported, note that the use of the -webkit- vendor prefix denotes intended 'support' in webkit browsers, IE does not use the webkit engine.

Typically, you are not able to determine / override / code the option to print background colors and images. One approach is to utilise other properties / elements, such as using img elements for actual images, or using pseudo elements with extremely wide borders to mimic background colors. However, often neither is practical.

Unfortunately support of even the print or paged media modules accross browsers is terrible. Indeed, the CSS working group has a large discussion around the whole topic