display pages as post sliders in catch everest child theme

// Put this into functions.php of a child theme of catch everest wordpress theme

/**
 * Shows Featued Post Slider
 *
 * @uses catcheverest_header action to add it in the header
 */
function catcheverest_post_sliders_custom() {
    //delete_transient( 'catcheverest_post_sliders' );

    global $post;
    global $catcheverest_options_settings;
    $options = $catcheverest_options_settings;


    if( ( !$catcheverest_post_sliders = get_transient( 'catcheverest_post_sliders' ) ) && !empty( $options[ 'featured_slider' ] ) ) {
        echo '<!-- refreshing cache -->';

        $catcheverest_post_sliders = '
        <div id="main-slider" class="container">
            <section class="featured-slider">';
                $get_featured_posts = new WP_Query( array(
                    'posts_per_page' => $options[ 'slider_qty' ],
                    'post_type' => array( 'post', 'page' ),
                    'post__in'       => $options[ 'featured_slider' ],
                    'orderby'        => 'post__in',
                    'ignore_sticky_posts' => 1 // ignore sticky posts
                ));
                $i=0; while ( $get_featured_posts->have_posts()) : $get_featured_posts->the_post(); $i++;
                    $title_attribute = apply_filters( 'the_title', get_the_title( $post->ID ) );
                    $excerpt = get_the_excerpt();
                    if ( $i == 1 ) { $classes = "post hentry slides displayblock"; } else { $classes = "post hentry slides displaynone"; }
                    $catcheverest_post_sliders .= '
                    <article class="'.$classes.'">
                        <figure class="slider-image">
                            <a title="Permalink to '.the_title('','',false).'" href="' . get_permalink() . '">
                                '. get_the_post_thumbnail( $post->ID, 'slider', array( 'title' => esc_attr( $title_attribute ), 'alt' => esc_attr( $title_attribute ), 'class'  => 'pngfix' ) ).'
                            </a>
                        </figure>
                        <div class="entry-container">
                            <header class="entry-header">
                                <h1 class="entry-title">
                                    <a title="Permalink to '.the_title('','',false).'" href="' . get_permalink() . '">'.the_title( '<span>','</span>', false ).'</a>
                                </h1>
                            </header>';
                            if( $excerpt !='') {
                                $catcheverest_post_sliders .= '<div class="entry-content">'. $excerpt.'</div>';
                            }
                            $catcheverest_post_sliders .= '
                        </div>
                    </article><!-- .slides -->';
                endwhile; wp_reset_query();
                $catcheverest_post_sliders .= '
            </section>
            <div id="slider-nav">
                <a class="slide-previous">&lt;</a>
                <a class="slide-next">&gt;</a>
            </div>
            <div id="controllers"></div>
        </div><!-- #main-slider -->';

    set_transient( 'catcheverest_post_sliders', $catcheverest_post_sliders, 86940 );
    }
    echo $catcheverest_post_sliders;
} // catcheverest_post_sliders

/**
 * Shows Slider
 */
function catcheverest_slider_display_custom() {
    global $catcheverest_options_settings;
    $options = $catcheverest_options_settings;

    $enableslider = $options[ 'enable_slider' ];
    $featuredslider = $options[ 'featured_slider' ];

    if ( ( $enableslider == 'enable-slider-allpage' ) || ( ( is_home() || is_front_page() ) && $enableslider == 'enable-slider-homepage' ) ) :
        // This function passes the value of slider effect to js file
        if ( function_exists( 'catcheverest_pass_slider_value' ) ) : catcheverest_pass_slider_value(); endif;
        // Select Slider
        if ( !empty( $featuredslider ) ) {
            catcheverest_post_sliders_custom();
        }
        else {
            catcheverest_default_sliders();
        }
    endif;
}

function catcheverest_exchange_slider_display_function() {
    remove_action( 'catcheverest_before_main', 'catcheverest_slider_display', 10);
    add_action( 'catcheverest_before_main', 'catcheverest_slider_display_custom');
}
add_action( 'init', 'catcheverest_exchange_slider_display_function' );