sidebar

register_sidebar( array(
		'name' => 'abc',
		'id' => 'xyz',
		'before_widget' => '<div>',
		'after_widget' => '</div> <!-- end .fwidget -->',
		'before_title' => '<h4 class="widgettitle">',
		'after_title' => '</h4>',
		) );
<?php get_sidebar( 'xyz' ); ?>
<?php dynamic_sidebar( 'xyz' ); ?>

klasa diva od kategorii

<div class="<?php foreach(get_the_category() as $category) {echo $category->slug . ' ';}?>">m</div>

menu

function register_my_menu() {
  register_nav_menu('new-menu',__( 'New Menu' ));
}
add_action( 'init', 'register_my_menu' );
<?php wp_nav_menu( array( 'theme_location' => 'new-menu' ) ); ?>

child theme

Theme Name:   name-child
Template:     name

@import url("../name/style.css");

footer

&copy; <a href="/" title="<?php echo esc_attr( get_bloginfo( 'name' ) ); ?>"> <?php echo esc_attr( get_bloginfo( 'name' ) ); ?> </a>

footer

<?php echo date("Y"); ?>
<?php echo get_the_date(); ?>

pokaż tylko na stronie id:5234

<?php
if(is_page(5234)){
?>
 <?php dynamic_sidebar( 'xyz' ); ?>

<?php } 
else {
echo  '';
}
?>

pokaż tylko w danym języku

<?php if(ICL_LANGUAGE_CODE=='pl'): ?>
<a href="/ciasteczka">Ciasteczka</a>
<?php elseif(ICL_LANGUAGE_CODE=='en'): ?>
<a href="/en/cookies">Cookies</a>
<?php endif; ?>

dodanie nowych wyrażeń do tłumaczenia poprzez polylang

pll_register_string('title', 'O Autorze');

<h2><?php pll_e("O Autorze", "templaty"); ?></h2>

wyświetlaj na stronie głównej

<?php if ( is_front_page() ) { ?>
text here
<?php } else { ?>
 text here
<?php } ?>
add_post_type_support( 'page', 'excerpt' );
function custom_excerpt_length( $length ) {
	return 20;
}
add_filter( 'excerpt_length', 'custom_excerpt_length', 999 );
function new_excerpt_more( $more ) {
	return '...';
}
add_filter('excerpt_more', 'new_excerpt_more');
pll_register_string('title', 'Czytaj dalej');
add_image_size( 'isat-thumb', 770, 9999 ); 
function themeslug_theme_customizer( $wp_customize ) {

$wp_customize->add_section( 'themeslug_logo_section' , array(
    'title'       => __( 'Logo', 'themeslug' ),
    'priority'    => 30,
    'description' => 'Upload a logo to replace the default site name and description in the header',
) );

$wp_customize->add_setting( 'themeslug_logo' );

$wp_customize->add_control( new WP_Customize_Image_Control( $wp_customize, 'themeslug_logo', array(
    'label'    => __( 'Logo', 'themeslug' ),
    'section'  => 'themeslug_logo_section',
    'settings' => 'themeslug_logo',
) ) );
}
add_action( 'customize_register', 'themeslug_theme_customizer' );

Adding a logo uploader to your WordPress theme with the Theme Customizer

Add a custom logo uploader to the WordPress theme customizer

add_theme_support( 'post-thumbnails' ); 

 <?php  
    // check if the post has a Post Thumbnail assigned to it.
if ( has_post_thumbnail() ) {
	the_post_thumbnail();
} 
the_content();
?>
<article class="post <?php global $post; echo $post->post_name; ?>">
.gray { 
filter: url("data:image/svg+xml;utf8,&lt;svg xmlns=\'http://www.w3.org/2000/svg\'&gt;&lt;filter id=\'grayscale\'&gt;&lt;feColorMatrix type=\'matrix\' values=\'0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0 0 0 1 0\'/&gt;&lt;/filter&gt;&lt;/svg&gt;#grayscale"); /* Firefox 10+, Firefox on Android */
    filter: gray; /* IE6-9 */
-webkit-filter: grayscale(100%); /* Chrome 19+, Safari 6+, Safari 6+ iOS */
}
.gray:hover {
    filter: url("data:image/svg+xml;utf8,&lt;svg xmlns=\'http://www.w3.org/2000/svg\'&gt;&lt;filter id=\'grayscale\'&gt;&lt;feColorMatrix type=\'matrix\' values=\'1 0 0 0 0, 0 1 0 0 0, 0 0 1 0 0, 0 0 0 1 0\'/&gt;&lt;/filter&gt;&lt;/svg&gt;#grayscale");
    -webkit-filter: grayscale(0%);
}
<article class="post" <?php
if ( $thumbnail_id = get_post_thumbnail_id() ) {
        if ( $image_src = wp_get_attachment_image_src( $thumbnail_id, 'medium' ) )
            printf( ' style="background-image: url(%s);"', $image_src[0] );     
    }

?>>