Wordpress jQuery is not defined error

Question

Hi I have just learned how to add jQuery to wordpress themes and it works but an error keeps appearing in the wordpress development tool.Here is the code that I posted:

    function register_js(){
    if(!is_admin()){
        wp_deregister_script('jquery');
        wp_register_script('jquery' , 'http://ajax.googleapis.com/ajax/libs/jquery/1.8.0/jquery.min.js');
        wp_register_script('quicksand', get_template_directory_uri() . '/js/quicksand.js', 'jquery');
        wp_register_script('easing', get_template_directory_uri() . '/js/easing.js', 'jquery');
        wp_register_script('custom', get_template_directory_uri() . '/js/main.js', 'jquery', '1.0', TRUE);
        wp_register_script('prettyPhoto', get_template_directory_uri() . '/js/jquery.prettyPhoto.js', 'jquery');


        wp_enqueue_script('jquery');
        wp_enqueue_script('quicksand');
        wp_enqueue_script('prettyPhoto');
        wp_enqueue_script('easing');
        wp_enqueue_script('custom');
    }

}
add_action('wp_enqueue_scripts', 'register_js');

Not the this is that I used to get the error $ and jQuery is not defined.To solve the $ problem in my main js file I used this:

jQuery(document).ready(function($) {})

Now I am only getting this errors:

Error: ReferenceError: jQuery is not defined
Source File: http://localhost/wordpress/wp-content/themes/01MyWork/js/quicksand.js
Line: 307


Error: ReferenceError: jQuery is not defined
Source File: http://localhost/wordpress/wp-content/themes/01MyWork/js/easing.js
Line: 39

Error: ReferenceError: jQuery is not defined
Source File: http://localhost/wordpress/wp-content/themes/01MyWork/js/main.js
Line: 2

The scripts seem to work the only problem is that this error is being thrown for every script that I load.How can I solve this?

Answer 1

Your primary problem is that you are de-registering core jQuery. Don't do that. Ever. Period. If you get rid of that, your other scripts will work properly. Just do this:

function wpse62373_register_js() {
    if ( ! is_admin() ) {
        wp_enqueue_script('quicksand', get_template_directory_uri() . '/js/quicksand.js', array( 'jquery' ) );
        wp_enqueue_script('easing', get_template_directory_uri() . '/js/easing.js', array( 'jquery' ) );
        wp_enqueue_script('custom', get_template_directory_uri() . '/js/main.js', array( 'jquery' ), '1.0', TRUE);
        wp_enqueue_script('prettyPhoto', get_template_directory_uri() . '/js/jquery.prettyPhoto.js', array( 'jquery' ) );    
    }

}
add_action( 'wp_enqueue_scripts', 'wpse62373_register_js' );

There are ways to replace core WordPress scripts properly, but I won't facilitate a bad practice such as replacing a core WordPress script by providing the answer.

Answer 2

I think your $deps need to be an array.

Example:

<?php   
wp_enqueue_script('jquerylib', 'http://ajax.googleapis.com/ajax/libs/jquery/1.6.4/jquery.min.js');  
wp_enqueue_script('myscript', bloginfo('template_url').'/js/myScript.js'__FILE__), array('jquerylib'));  
?> 

not

<?php   
wp_enqueue_script('jquerylib', 'http://ajax.googleapis.com/ajax/libs/jquery/1.6.4/jquery.min.js');  
wp_enqueue_script('myscript', bloginfo('template_url').'/js/myScript.js'__FILE__), 'jquerylib');  
?>

like you did.

ref: http://codex.wordpress.org/Function_Reference/wp_register_script -> $deps