Alter Custom Background Behaviour

By default the custom background is applied on the body. If you want to apply it on another element, you can use this function to customize any background parameter you want, as well as the element on which it’s applied.

Code Snippet:

// Activate custom background and set callback function
if ( function_exists( 'add_theme_support' ) ) {
    $defaults = array(
        'default-color' => '000000',
        'default-image' => get_template_directory_uri() . '/img/background.png',
        'wp-head-callback' => 'my_theme_background_cb',
        'admin-head-callback'    => '',
        'admin-preview-callback' => ''
    );
    add_theme_support( 'custom-background', $defaults );
}
// Callback function to alter custom background behavior
function my_theme_background_cb() {
    $background = get_background_image();
    $color = get_background_color();
 
    if ( ! $background && ! $color )
        return;
 
    $style = $color ? "background-color: #$color;" : '';
 
    if ( $background ) {
        $image = " background-image: url('$background');";
 
        $repeat = get_theme_mod( 'background_repeat', 'repeat' );
        if ( ! in_array( $repeat, array( 'no-repeat', 'repeat-x', 'repeat-y', 'repeat' ) ) )
                $repeat = 'repeat';
        $repeat = " background-repeat: $repeat;";
 
        $position = get_theme_mod( 'background_position_x', 'left' );
        if ( ! in_array( $position, array( 'center', 'right', 'left' ) ) )
                $position = 'left';
        $position = " background-position: top $position;";
 
        $attachment = get_theme_mod( 'background_attachment', 'scroll' );
        if ( ! in_array( $attachment, array( 'fixed', 'scroll' ) ) )
                $attachment = 'scroll';
        $attachment = " background-attachment: $attachment;";
 
        $style .= $image . $repeat . $position . $attachment;
    }
?>
    <!-- You can set any class or id target here -->
    <style type="text/css" id="custom-background-css">;
        .main { <?php echo trim( $style ); ?> }
    </style>
<?php } ?>

Posted in Pure hacks, Images