Load Javascript for a widget Worpress

Question

I want to load a special Javascript File just when the widget is loaded in the sidebar. Where do I have to put my wp_enqueue_script(...) lines?

class controller_widget extends WP_Widget {
    function controller_widget() {
        $this->color = "red";

        $this->dir = plugin_dir_url(__FILE__);
        $widget_ops = array('classname' => 'controller_widget', 'description' => __('Benutzerfreundlicher Controller zur eingrenzung von Objekten'));
        $control_ops = array('width' => 350, 'height' => 400);
        $this->WP_Widget('controller_widget', __('Controller'), $widget_ops, $control_ops);

        // At the moment I load the code here, but I want to proof that it is just loaded when the widget really is shown in the sidebar.
        }
    }

    function widget( $args, $instance ) {...}
}

Thank you!

Answer 1

Put it in the widget script file itself. This method will ensure that your script is loaded i the appropriate place of the DOM.