Help with loop function code and footer by month

Hi this is Charls.
I would like to get help with this please. I’m using this code to show content in header and I would like to get help with footer:

the-events-calendar\lib\widget-list.class.php

header_widget();
tribe_get_template_part( 'widgets/list-widget' );
footer_widget();

for header_widget function is a copy of header function using in the-events-calendar\public\template-tags\loop.php

This is the function with some modifications:

function header_widget() {

		/* Month and year separators (on every month and year change) */

		$show_headers = apply_filters( 'tribe_events_list_show_date_headers', true );

		$html = '';

		if ($show_headers) {

			global $post, $wp_query;

			$event_year = tribe_get_start_date( $post, false, 'Y' );
			$event_month = tribe_get_start_date( $post, false, 'm' );

			if ($wp_query->current_post > 0) {
				$prev_post = $wp_query->posts[$wp_query->current_post - 1];
				$prev_event_year = tribe_get_start_date( $prev_post, false, 'Y' );
				$prev_event_month = tribe_get_start_date( $prev_post, false, 'm' );
			}

			/*
			 * If the event month changed since the last event in the loop,
			 * or is the same month but the year changed.
			 *
			 */
			if ( $wp_query->current_post === 0 || ( $prev_event_month != $event_month || ( $prev_event_month == $event_month && $prev_event_year != $event_year ) ) ) {
				$html .= sprintf( "<div class='another-month-class'><div style='height: 10px;' class='header-widget-content'>");
			}

			echo apply_filters('header_widget', $html, $event_month, $event_year);
		}
	}

This is the original function you used in the plugin

function tribe_events_list_the_date_headers_widget() {

		/* Month and year separators (on every month and year change) */

		$show_headers = apply_filters( 'tribe_events_list_show_date_headers', true );

		$html = '';

		if ($show_headers) {

			global $post, $wp_query;

			$event_year = tribe_get_start_date( $post, false, 'Y' );
			$event_month = tribe_get_start_date( $post, false, 'm' );

			if ($wp_query->current_post > 0) {
				$prev_post = $wp_query->posts[$wp_query->current_post - 1];
				$prev_event_year = tribe_get_start_date( $prev_post, false, 'Y' );
				$prev_event_month = tribe_get_start_date( $prev_post, false, 'm' );
			}

			/*
			 * If the event month changed since the last event in the loop,
			 * or is the same month but the year changed.
			 *
			 */
			if ( $wp_query->current_post === 0 || ( $prev_event_month != $event_month || ( $prev_event_month == $event_month && $prev_event_year != $event_year ) ) ) {
				$html .= sprintf( "<span class='tribe-events-list-separator-month accordion_toggle'>%s</span>", tribe_get_start_date( $post, false, 'F Y' ) );
			}

			/*
			 * If this event year is different to the year of the previous event in the loop,
			 * and it's not it's not the first event in the loop (we don't want to start the loop with a year separator)
			 */
			if ( $wp_query->current_post > 0 && $prev_event_year != $event_year ) {
				$html .= sprintf( "<span class='tribe-events-list-separator-year'>%s</span>", $event_year );
			}

			echo apply_filters('tribe_events_list_the_date_headers_widget', $html, $event_month, $event_year);
		}
	}

As you can see, the change I did is basically in the output. And I would like you could help to add content in footer with a similar function. I just tried this:

function footer_widget() {

		/* Month and year separators (on every month and year change) */

		$show_footer = apply_filters( 'tribe_events_list_show_date_footer', true );

		$html = '';

		if ($show_footer) {

			global $post, $wp_query;

			$event_year = tribe_get_start_date( $post, false, 'Y' );
			$event_month = tribe_get_start_date( $post, false, 'm' );

			if ($wp_query->current_post > 0) {
				$next_post = $wp_query->posts[$wp_query->current_post + 1];
				$next_event_year = tribe_get_start_date( $next_post, false, 'Y' );
				$next_event_month = tribe_get_start_date( $next_post, false, 'm' );
			}

			/*
			 * If the event month changed since the last event in the loop,
			 * or is the same month but the year changed.
			 *
			 */
			if ( $wp_query->current_post === 0 || ( $next_event_month != $event_month || ( $next_event_month == $event_month && $next_event_year != $event_year ) ) ) {
				$html .= sprintf( "<div class='footer-cont'><div></div>");
			}

			echo apply_filters('footer_widget', $html, $event_month, $event_year);
		}
	}

As you can see, I’m trying to add separate header and footer by month with a custom div.

I hope you could help me with this.
Thanks.

http://wordpress.org/plugins/the-events-calendar/