我试图将一个变量从一个函数（呈现一个短代码）传递到另一个将google字体排队的函数。我正在使用过滤器。由于函数连接到add_shortcode, 我想我不能直接添加过滤器。

我正在使用中介函数。当我做print_r 对于中的中介函数wp_footer, 它显示变量，但当我将其挂接到add_filter ，并将其打印到wp_footer.

function first_shortcode( $atts , $content = null ) {

    $atts = shortcode_atts(
        array(
            \'typography\' => \'\',
        ),
        $atts
    );

    //Other shortcode stuffs

    if ( $atts[\'typography\'] ) {
        $typo = $atts[\'typography\'];

        $font = array();
        $font[\'family\'] = $typo[\'font\'];
        $font[\'weight\'] = $typo[\'weight\'];

        googlefont_filter_callback( $font );
    }

}
add_shortcode( \'first\', \'first_shortcode\' );

function second_shortcode( $atts , $content = null ) {

    $atts = shortcode_atts(
        array(
            \'typography\' => \'\',
        ),
        $atts
    );

    //Other shortcode stuffs

    if ( $atts[\'typography\'] ) {
        $typo = $atts[\'typography\'];

        $font = array();
        $font[\'family\'] = $typo[\'font\'];
        $font[\'weight\'] = $typo[\'weight\'];

        googlefont_filter_callback( $font );
    }

}
add_shortcode( \'first\', \'second_shortcode\' );  

调解人职能：

function googlefont_filter_callback( $fonts=array() ) {

    return $fonts;

}
add_filter( \'googlefont_loader\', \'googlefont_filter_callback\' );  

以及将字体排队的功能：

function googlefont_loader( $fonts=array() ) {

    $fonts = array();
    $fonts = apply_filters( \'googlefont_loader\', $fonts );

    $new_array = array();

    foreach ($fonts as $font){
        $new_value = !empty($new_array[$font[\'family\']]) ? $new_array[$font[\'family\']].\',\'.$font[\'weight\'] : $font[\'weight\'];
        $new_array[$font[\'family\']] =  $new_value;
    }

    /*
    $out = \'\';
    foreach( $new_array as $family => $weight ) {

        $out .= $family . \':\' . $weight . \'|\';  
    }
    if ( !empty($fonts) ) {
        wp_register_style( \'purewpns-googlefonts\', \'//fonts.googleapis.com/css?family=\' . rtrim($out, \'|\') );
        wp_enqueue_style( \'purewpns-googlefonts\' );
    }
    */

    echo \'<pre>\' . print_r( $fonts, true ). \'</pre>\';

}
add_action( \'wp_footer\', \'purewpns_googlefont_loader\' );
//add_action( \'wp_enqueue_scripts\', \'purewpns_googlefont_loader\' );

现在，回声进来了googlefont_loader 返回空数组

Array
(
)  

我做错了什么？或者，这是因为挂钩的发射时间？

add_action( \'wp_footer\', \'purewpns_googlefont_loader\' );

googlefont_filter_callback( $font );

$fonts = apply_filters( \'googlefont_loader\', $fonts );

function googlefont_filter_callback( $fonts=array() ) {
return apply_filters( \'googlefont_loader\', $fonts );
}

add_filter( \'googlefont_loader\' function( $fonts ) {
 var_dump( $fonts);
return $fonts;
});