Plugin won't activate, fatal error (widget class not found)

Question

I've been putting together a simple WordPress plugin that employs a sidebar widget and shortcode. One user has reported the following error when trying to activate the plugin on their local WP installation:

Plugin could not be activated because it triggered a fatal error.

Fatal error: Class 'Example_Widget' not found in /Applications/MAMP/htdocs/wordpress/wp-content/plugins/exampleplugin/exampleplugin.php on line 30

Here's the code in exampleplugin.php, beginning with line 29:

$example_plugin = new Example_Plugin;
$example_widget = new Example_Widget;

class Example_Plugin {
    ...
}

I'm fairly new to OOP in PHP, and can't figure out what's causing a fatal error for this user. The plugin works fine for me, making this all the more mysterious.

Answer 1

You should not need to instantiate the widget class at the top of your code, because of the register_widget function hooked from your main class does that work for you.

EDIT: Wordpress already instantiates your class.