I'm not sure what you still understand, but here is the solution to your problem.
Firstly, you do not want to directly edit the widget. If you upgrade Wordpress, your code will be overwritten. Wordpress is very extensible, so you do not need to edit the code directly.
Ideally, you should create a plugin. If you want to know, read this http://codex.wordpress.org/Writing_a_Plugin
Another great thing about Wordpress is that they have very good documentation.
However, for simplicity, we just do it in functions.php in the theme you are using. You can find it at /wp-content/themes/your_theme/functions.php
Here is a modified version of the sample code in your question:
//First we need to change the name of the Widget. I just named it RT_Widget_Text, so just be aware that you can change it to anything you want and to replace all instances of that text. Just make sure to not name it WP_Widget_Text class RT_Widget_Text extends WP_Widget { function __construct() { //I made a change here. I changed the class name to widget_double_text. This probably has no effect, but I just changed it for good measure. $widget_ops = array('classname' => 'widget_double_text', 'description' => __('Arbitrary text or HTML')); $control_ops = array('width' => 400, 'height' => 350); //Here is the important part. Change the "text" to "double_text" and "Text" to "Text 2" or to some other text that will identify the widget. parent::__construct('double_text', __('Text 2'), $widget_ops, $control_ops); } function widget( $args, $instance ) { extract($args); $title = apply_filters( 'widget_title', empty( $instance['title'] ) ? '' : $instance['title'], $instance, $this->id_base ); $text = apply_filters( 'widget_text', empty( $instance['text'] ) ? '' : $instance['text'], $instance ); //I changed this to $text2 = instead of $text = //This would have caused the first text section to display you text2 and your text2 to display nothing. //I wonder if this was your issue? $text2 = apply_filters( 'widget_text', empty( $instance['text2'] ) ? '' : $instance['text2'], $instance ); echo $before_widget; if ( !empty( $title ) ) { echo $before_title . $title . $after_title; } ?> <div class="textwidget"> <?php echo !empty( $instance['filter'] ) ? wpautop( $text ) : $text; ?> </div> <div class="textwidget2"> <?php echo !empty( $instance['filter'] ) ? wpautop( $text2 ) : $text2; ?> </div> <?php echo $after_widget; } function update( $new_instance, $old_instance ) { $instance = $old_instance; $instance['title'] = strip_tags($new_instance['title']); if ( current_user_can('unfiltered_html') ) { $instance['text'] = $new_instance['text']; $instance['text2'] = $new_instance['text2']; } else { $instance['text'] = stripslashes( wp_filter_post_kses( addslashes($new_instance['text']) ) ); // wp_filter_post_kses() expects slashed $instance['text2'] = stripslashes( wp_filter_post_kses( addslashes($new_instance['text2']) ) ); // wp_filter_post_kses() expects slashed } $instance['filter'] = isset($new_instance['filter']); return $instance; } function form( $instance ) { $instance = wp_parse_args( (array) $instance, array( 'title' => '', 'text' => '', 'text2' => '' ) ); $title = strip_tags($instance['title']); $text = esc_textarea($instance['text']); $text2 = esc_textarea($instance['text2']); ?> <p><label for="<?php echo $this->get_field_id('title'); ?>"><?php _e('Title:'); ?></label> <input class="widefat" id="<?php echo $this->get_field_id('title'); ?>" name="<?php echo $this->get_field_name('title'); ?>" type="text" value="<?php echo esc_attr($title); ?>" /></p> <textarea class="widefat" rows="16" cols="20" id="<?php echo $this->get_field_id('text'); ?>" name="<?php echo $this->get_field_name('text'); ?>"><?php echo $text; ?></textarea> <textarea class="widefat" rows="8" cols="20" id="<?php echo $this->get_field_id('text2'); ?>" name="<?php echo $this->get_field_name('text2'); ?>"><?php echo $text2; ?></textarea> <p><input id="<?php echo $this->get_field_id('filter'); ?>" name="<?php echo $this->get_field_name('filter'); ?>" type="checkbox" <?php checked(isset($instance['filter']) ? $instance['filter'] : 0); ?> /> <label for="<?php echo $this->get_field_id('filter'); ?>"><?php _e('Automatically add paragraphs'); ?></label></p> <?php } } //Now you need to register your widget. Remember to change it to whatever you named your widget add_action( 'widgets_init', create_function( '', 'register_widget( "RT_Widget_Text" );' ) );
With all of this, I think that your mistake may have been a simple typo in your widget( $args, instance) method here:
$text = apply_filters( 'widget_text', empty( $instance['text'] ) ? '' : $instance['text'], $instance ); $text = apply_filters( 'widget_text2', empty( $instance['text2'] ) ? '' : $instance['text2'], $instance );
Note that here you set $text = twice. So you basically rewrote the meaning of the text and replaced it with text2. And then it remains text2 null.
If this is not your problem, this may be due to registering the widget as "text", as this is done by WP_Widget_Text. This is unlikely, since I assume that you edited the WP_Widget_Text class directly.