Ticket #30351: foo_widget.php

<?php
/**
 * Adds Foo_Widget widget.
 */
class Foo_Widget extends WP_Widget {

        /**
         * Register widget with WordPress.
         */
        function __construct() {
                parent::__construct(
                        'foo_widget', // Base ID
                        __( 'Widget Title', 'text_domain' ), // Name
                        array( 'description' => __( 'A Foo Widget', 'text_domain' ), ) // Args
                );
        }

        /**
         * Front-end display of widget.
         *
         * @see WP_Widget::widget()
         *
         * @param array $args     Widget arguments.
         * @param array $instance Saved values from database.
         */
        public function widget( $args, $instance ) {
        
    echo $args['before_widget'];
                if ( ! empty( $instance['title'] ) ) {
                        echo $args['before_title'] . apply_filters( 'widget_title', $instance['title'] ). $args['after_title'];
                }
                echo __( 'Hello, World!', 'text_domain' );
                echo $args['after_widget'];
        }

        /**
         * Back-end widget form.
         *
         * @see WP_Widget::form()
         *
         * @param array $instance Previously saved values from database.
         */
        public function form( $instance ) {
    $title = ! empty( $instance['title'] ) ? $instance['title'] : 'My Widget';
    $message = ! empty( $instance['message'] ) ? $instance['message'] : '<i class="icon"></i> This I tag is the source of the problem';
                ?>
                <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>
                <p>
                        <label for="<?php echo $this->get_field_id( 'message' ); ?>"><?php _e( 'Message:' ); ?></label> 
                        <input class="widefat" id="<?php echo $this->get_field_id( 'message' ); ?>" name="<?php echo $this->get_field_name( 'message' ); ?>" type="text" value="<?php echo esc_attr( $message ); ?>">
                </p>
                <?php
        }

        /**
         * Sanitize widget form values as they are saved.
         *
         * @see WP_Widget::update()
         *
         * @param array $new_instance Values just sent to be saved.
         * @param array $old_instance Previously saved values from database.
         *
         * @return array Updated safe values to be saved.
         */
        public function update( $new_instance, $old_instance ) {
                $instance = array();
                $instance['title'] = ( ! empty( $new_instance['title'] ) ) ? strip_tags( $new_instance['title'] ) : '';
                $instance['message'] = ( ! empty( $new_instance['message'] ) ) ? wp_kses_post( $new_instance['message'] ) : '';

                return $instance;
        }

} // class Foo_Widget

// register Foo_Widget widget
function register_foo_widget() {
                register_widget( 'Foo_Widget' );
}
add_action( 'widgets_init', 'register_foo_widget' );