您可以使用复选框创建自己的元框，并仅选择选中以下内容的帖子：

添加metabox代码

/* Define the custom box */
add_action( \'add_meta_boxes\', \'my_slider_add_custom_box\' );

/* Do something with the data entered */
add_action( \'save_post\', \'my_slider_save_postdata\' );

/* Adds a box to the main column on the Post and Page edit screens */
function my_slider_add_custom_box() {
    add_meta_box( 
        \'my_slider_sectionid\',
        __( \'my slider\', \'my_slider_textdomain\' ),
        \'my_slider_inner_custom_box\',
        \'post\' 
    );
}

/* Prints the box content */
function my_slider_inner_custom_box() {
    global $post;
    // Use nonce for verification
    wp_nonce_field( plugin_basename( __FILE__ ), \'my_slider_noncename\' );
    $saved = get_post_meta($post->ID,\'my_slider_field\',true);
    // The actual fields for data entry
    echo \'<label for="my_slider_field">\';
    _e("Check the box if you want this post to show in the slider", \'myplugin_textdomain\' );
    echo \'</label> \';
    echo \'<input type="checkbox" id="my_slider_field" name="my_slider_field" value="yes"\';
    echo  ($saved) ? \'checked\': \'\';
    echo \'/>\';
}

/* When the post is saved, saves our custom data */
function my_slider_save_postdata( $post_id ) {
      // verify if this is an auto save routine. 
      // If it is our form has not been submitted, so we dont want to do anything
      if ( defined( \'DOING_AUTOSAVE\' ) && DOING_AUTOSAVE ) 
          return;

      // verify this came from the our screen and with proper authorization,
      // because save_post can be triggered at other times

      if ( !wp_verify_nonce( $_POST[\'my_slider_noncename\'], plugin_basename( __FILE__ ) ) )
          return;

      // OK, we\'re authenticated: we need to find and save the data
        $old = get_post_meta($post_id,\'my_slider_field\',true);
      if (isset($_POST[\'my_slider_field\']) && $_POST[\'my_slider_field\'] == "yes"){
            update_post_meta($post_id,\'my_slider_field\',true);
      }else{
        if (!empty($old)){
            delete_post_meta($post_id,\'my_slider_field\');
        }
      }
}

$args = array(
    \'posts_per_page\' => -1
    \'meta_query\' => array(
        array(
            \'key\' => \'my_slider_field\',
            \'value\' => true
        )
    );
$slider_query = new WP_Query($args);