atravelblog/functions.php

<?php

add_action( 'wp_enqueue_scripts', 'td_theme_styles' );
function td_theme_styles() {
    wp_enqueue_style( 'parent-style', get_template_directory_uri() . '/style.css' );
    wp_enqueue_script(
      'google-maps',
      '//maps.googleapis.com/maps/api/js?key=AIzaSyDHNT102YHu-TP50F78bPyvf5ia6K6cjU8&callback=initMap',
      array(),
      '1.0',
      true
    );
}

// Add google API key
function my_acf_google_map_api( $api ){
	$api['key'] = 'AIzaSyDHNT102YHu-TP50F78bPyvf5ia6K6cjU8';
	return $api;
}

add_filter('acf/fields/google_map/api', 'my_acf_google_map_api');


// Related posts function
function atravelblog_related_posts() {
	echo('<div class="related-posts posts section-inner">');
	global $post;
	$thisID = get_the_ID();
	$cat = get_the_category()[0]->name;
	if ( $cat == 'Urlaub' ){
		$tagebuch = new WP_Query( array( 'category_name' => 'Tagebuch' ) );
	    if ($tagebuch->have_posts()) :
		    echo('<h4>Tagebuch Einträge:</h4>');
	        while ( $tagebuch->have_posts() ) : $tagebuch->the_post();
		        global $post;
		        if($thisID == get_field('urlaub')->ID){
			        get_template_part( 'content', get_post_format() );
		        }
	        endwhile;
        endif;
    } elseif($cat == 'Tour') {
        $urlaub = new WP_Query(array('p' => get_field('urlaub')[0]));
		if ($urlaub->have_posts()) :
			while ( $urlaub->have_posts() ) : $urlaub->the_post();
				global $post;
				get_template_part( 'content', get_post_format() );
			endwhile;
		endif;
    }
	echo('<div class="clear"></div>');
    echo('</div> <!-- /related-posts -->');
    wp_reset_query();
}