Take the 2-minute tour ×
WordPress Development Stack Exchange is a question and answer site for WordPress developers and administrators. It's 100% free, no registration required.

I recently released a plugin, WP Coda Slider, that uses shortcodes to add a jQuery slider to any post or page. I am adding an options page in the next version and I would like to include some CSS options but I don't want the plugin to add the style choices as inline CSS. I want the choices to be dynamically added to the CSS file when it's called.

I would also like to avoid using fopen or writing to a file for security issues.

Is something like this easy to accomplish or would I be better off just adding the style choices directly to the page?

share|improve this question
    
@Chris_O: I have been thinking about almost exactly the same thing. What I'm wanting is a way to call wp_enqueue_style() (and wp_enqueue_script()) with a function name instead of a filename and have my function generate the CSS (or JS) but still have it ultimately included via a linked stylesheet. As far as I know this isn't possible with the wp_equeue_*() functions. Maybe we should submit a trac ticket? –  MikeSchinkel Sep 7 '10 at 6:44
    
@MikeSchinkel: That would be a very logical way to use the wp_enqueue functions. I would add support to that ticket. –  Chris_O Sep 7 '10 at 7:24
    
@Chris_O: I just saw @Doug's answer; I made a bad assumption you already knew that. Had I realized that was not the case I would have pointed you to here: wordpress.stackexchange.com/questions/556/#562 –  MikeSchinkel Sep 8 '10 at 0:12
    
@MikeSchinkel I knew about wp_register and wp_enqueue. I was looking for a way to build the style sheet based on the values from the plugin options page. –  Chris_O Sep 8 '10 at 0:37
    
@Chris_O: Ah. I like to think of myself as someone who can still see what others are missing in a solution even after I learn the solution (i.e most experts are not good teachers and though I'm not the best expert I'm generally a good teacher.) OTOH, this is one that I missed, sorry. :) –  MikeSchinkel Sep 8 '10 at 0:40

4 Answers 4

up vote 17 down vote accepted

Use wp_register_style and wp_enqueue_style to add the stylesheet. DO NOT simply add a stylesheet link to wp_head. Queuing styles allows other plugins or themes to modify the stylesheet if necessary.

Your stylesheet can be a .php file:

wp_register_style('myStyleSheet', 'my-stylesheet.php');
wp_enqueue_style( 'myStyleSheet');

my-stylesheet.php would look like this:

<?php
// We'll be outputting CSS
header('Content-type: text/css');

include('my-plugin-data.php');    
?>

body {
  background: <?php echo $my_background_variable; ?>;
  font-size: <?php echo $my_font_size; ?>;
}
share|improve this answer
3  
Additionally - as the values only change when the values on the option page are changed - you could generate the CSS file on save. You can store CSS files in the plugin directory as well, so this is a bit more performant then to run a PHP file on each CSS request with includes etc. . –  hakre Sep 7 '10 at 21:44
    
Thanks! worked well. But I got the fatal error get_option()... is undefined. Then I loaded the wp-config.php file and then fixed the issue. –  Sumith Harshan Jan 2 at 13:43

Dynamically building a CSS file and then loading it adds a HUGE performance burden to what should be a very low bandwidth deal of adding a CSS file, especially if there are variables in the CSS that are going to be processed through WP. Because it is two different files being created for one page load, WP starts up twice and runs all the DB queries twice, and it's a big mess.

If your slider is only going to be on one page, and you want the styles set dynamically, then your best bet is to add a style block to the header.

In order of performance:

  1. Add small block of styles in header, dynamically created - Very fast
  2. Add a non-dynamic stylesheet via wp_enqueue_style - Medium
  3. Add a dynamic stylesheet via wp_enqueue_style - Very Slow
share|improve this answer
    
@Dan-gayle Very good point. The plugin can be used on more than one page and some users are using it on 2 or 3 pages. It only enqueues the current static style sheet and js on pages that have the shortcode. –  Chris_O Sep 7 '10 at 17:25
    
I agree with Dan Gayle, even though you voted up my answer. Adding a small CSS block to wp_head would be much better performance-wise than requiring a separate stylesheet be downloaded on every page view (even if restricted to the few posts/pages with the shortcode). The only reason to use separate stylesheets in the first place is that they can be cached by the browser. Dynamic stylesheets can not be cached. –  Doug Sep 7 '10 at 17:56
1  
Is this still the right way to go about things? –  Dave Kiss May 21 '13 at 14:26

This is how I usually do it:

function build_stylesheet_url() {
    echo '<link rel="stylesheet" href="' . $url . 'stylesheetname.css?build=' . date( "Ymd", strtotime( '-24 days' ) ) . '" type="text/css" media="screen" />';
}

function build_stylesheet_content() {
    if( isset( $_GET['build'] ) && addslashes( $_GET['build'] ) == date( "Ymd", strtotime( '-24 days' ) ) ) {
        header("Content-type: text/css");
        echo "/* Something */";
        define( 'DONOTCACHEPAGE', 1 ); // don't let wp-super-cache cache this page.
        die();
    }
}

add_action( 'init', 'build_stylesheet_content' );
add_action( 'wp_head', 'build_stylesheet_url' );
share|improve this answer

I've had difficulty with all the recommendations of this ilk - maybe I'm a bit thick, or maybe contributors have lost the common touch.

I settled on coding this in the plug-in php file:-

echo "<link href='http://www.brittany-gite-holidays.co.uk/wp-content/plugins/flexavailability/css/css.css' type='text/css' rel='stylesheet' />";
echo "<link href='http://www.brittany-gite-holidays.co.uk/wp-content/plugins/flexavailability/css/public.css' rel='stylesheet' type='text/css'/>";

It seems to work. It only loads on those pages which use the plugin. It loads after the h1 tag which is fine by me. I can't see how it could be more efficient or more clear.

....but perhaps I'm wrong - I did say I was a bit thick.

share|improve this answer
    
You should only load <link> elements in the page head –  bungeshea Jan 18 '13 at 20:37
    
Yerss. That would be because your css is wanted to affect everything from the top of the page downwards. I'm happy to affect only what comes after the h1 tag. I couldn't make any of the examples work (I think they may be badly explained).Try it for yourself on some piece of test html. If i'm wrong tell me :) –  chazza Jan 19 '13 at 18:56

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.