Using tabs in admin widgets [closed]

The problem is that you’re not using unique IDs (#tabs, #tabs-1 …), because widgets have multiple instances (the same IDs are used by the instance form the “Available Widgets” area).

So just prepend or append the widget instance ID to your identifiers to make them unique:

...
<div id="tabs-<?php echo $this->id; ?>">
    <ul>
        <li><a href="#tabs-<?php echo $this->id; ?>-1">Tab One</a></li>
        <li><a href="#tabs-<?php echo $this->id; ?>-2">Tab Two</a></li>
    </ul>
    <div id="tabs-<?php echo $this->id; ?>-1">
        <p><?php _e('Textbox 1') ?>: <input class="widefat" name="<?php echo $this->get_field_name('text1'); ?>" type="text" value="<?php echo esc_attr($text1); ?>" /></p>
        <p><?php _e('Textarea 1') ?>: <textarea class="widefat" name="<?php echo $this->get_field_name('textarea1'); ?>" rows="8" cols="12"><?php echo esc_attr($textarea1); ?></textarea></p>
    </div>
    <div id="tabs-<?php echo $this->id; ?>-2">
        <p><?php _e('Textbox 2') ?>: <input class="widefat" name="<?php echo $this->get_field_name('text2'); ?>" type="text" value="<?php echo esc_attr($text2); ?>" /></p>
        <p><?php _e('Textarea 2') ?>: <textarea class="widefat" name="<?php echo $this->get_field_name('textarea2'); ?>" rows="8" cols="12"><?php echo esc_attr($textarea2); ?></textarea></p>
    </div>
</div>

<script type="text/javascript">
    jQuery(document).ready(function($){
        $("#tabs-<?php echo $this->id; ?>").tabs();
    });
</script>
...

Also, not sure if WP 3.3 fixed this issue, but after the first drag inside the sidebar, the widget-save action needs to be manually triggered for the id property to become available inside the form() function.