Common WordPress Code Mistakes

admin-targeting-hook.php

function user_edit_script( $hook ) {
    if ( 'profile.php' != $hook ) {
        return;
    }

    wp_enqueue_script( 'my-user-edit', plugin_dir_url( __FILE__ ) . 'js/my-user-edit.js' );
}
add_action( 'admin_enqueue_scripts', 'user_edit_script' );

child-theme-enqueue.php

add_action( 'wp_enqueue_scripts', 'enqueue_child_theme_styles', PHP_INT_MAX );
function enqueue_child_theme_styles() {
    wp_enqueue_style( 'parent-style', get_template_directory_uri().'/style.css' );
    wp_enqueue_style( 'child-style', get_stylesheet_uri(), array('parent-style')  );
}

child-theme-support.php

if( !function_exists( 'show_default_logo' ) ) {
	function show_default_logo() {
		echo '<img src="' . get_stylesheet_directory_uri() . '/images/logo.png" alt="Website Logo">';
	}
}

child-theme.php

/*
 Theme Name:   Twenty Fourteen Child
 Theme URI:    http://example.com/twenty-fourteen-child/
 Description:  Twenty Fourteen Child Theme
 Author:       John Doe
 Author URI:   http://example.com
 Template:     twentyfourteen
 Version:      1.0.0
 Tags:         light, dark, two-columns, right-sidebar, responsive-layout, accessibility-ready
 Text Domain:  twenty-fourteen-child
*/

enqueue-google-fonts.php

function my_frontend_styles() {
	wp_enqueue_style( 'my-google-fonts', '//fonts.googleapis.com/css?family=Droid+Serif:400,700|Roboto+Condensed:400,700' );
}

add_action( 'wp_enqueue_scripts', 'my_styles' );

function my_admin_styles() {
	wp_enqueue_style( 'my-google-fonts', '//fonts.googleapis.com/css?family=Droid+Serif:400,700|Roboto+Condensed:400,700' );
}
add_action( 'admin_enqueue_scripts', 'my_admin_styles' );

get_screen.php

function user_edit_script( $hook ) {
	$screen = get_current_screen();
	
	if( 'post' == $screen->base && 'page' == $screen->post_type ) {
		wp_enqueue_script( 'my-user-edit', plugin_dir_url( __FILE__ ) . 'js/my-user-edit.js' );
	}
}
add_action( 'admin_enqueue_scripts', 'user_edit_script' );

id-query.php

$posts = $wpdb->get_col( "SELECT ID FROM $wpdb->posts WHERE post_type = 'post' AND post_status='publish' ORDER BY post_date DESC " );

id-wpquery.php

$posts = new WP_Query( array(
	'post_type'   => 'post',
	'post_status' => 'publish',
	'fields'      => 'ids'
));

languages.php

add_action( 'plugins_loaded', 'myplugin_load_textdomain' );
function myplugin_load_textdomain() {
  load_plugin_textdomain( 'my-plugin', false, dirname( plugin_basename( __FILE__ ) ) . '/languages' ); 
}

no-autoload.php

$panel = array(
    'panel_color' => 'ff9900',
    'panel_position'  => 'left',
    'panel_size' => 'large'
);
 
add_option( 'my_plugin_panel_options', $plugin_options, '', 'no' );

plugin-options.php

$plugin_options = array(
    'selected_color' => 'ff9900',
    'favourite_post'  => 11,
    'favourite_shape' => 'icosahedron',
);

add_option( 'my_plugin_options', $plugin_options );

shortcode.php

add_action( 'wp_enqueue_scripts', 'my_styles' );
function my_frontend_styles() {
	wp_register_style( 'my-slider', get_template_directory_uri() . '/css/shortcode-slider.css' );
}


add_shortcode( 'my_slider', 'my_slider_display' );
function my_slider_display( $atts ) {
     wp_enqueue_style( 'my-slider' );
     
     // Code for the slider here
}

translatable.php

<?php _e( 'Populat Posts', 'mytextdomain' ) ?>

twentyfourteen-comment.php

if ( is_singular() && comments_open() && get_option( 'thread_comments' ) ) {
	wp_enqueue_script( 'comment-reply' );
}

uninstall.php

if ( ! defined( 'WP_UNINSTALL_PLUGIN' ) ) {
	exit;
}

delete_option( 'my_plugin_options' );
delete_option( 'my_plugin_panel_options' );

$wpdb->query( "DELETE FROM $wpdb->postmeta WHERE meta_key = 'my_plugin_data' " );