[Widget] #wordpress

functions.php

// Creating the widget
class spacer_widget extends WP_Widget {

	function __construct() {
		parent::__construct('spacer_widget', __('Spacer', 'spacer_widget_domain'), 	array( 'description' => __( 'Spacer widget', 'spacer_widget_domain' )));
	}

	public function widget( $args, $instance ) {
		$space_px = apply_filters( 'space_px', $instance['space_px'] );
		echo $args['before_widget'];
		echo $space_px;
		echo $args['after_widget'];
	}

	public function form( $instance ) {
		$space_px = ((isset( $instance[ 'space_px' ] ) )?$instance[ 'space_px' ]:20);
		?>
		<p>
		<label for="<?php echo $this->get_field_id( 'space_px' ); ?>"><?php _e( 'Space Size (px):' ); ?></label>
		<input class="widefat" id="<?php echo $this->get_field_id( 'space_px' ); ?>" name="<?php echo $this->get_field_name( 'space_px' ); ?>" type="text" value="<?php echo esc_attr( $space_px ); ?>" />
		</p>
		<?php
	}

	public function update( $new_instance, $old_instance ) {
		$instance = array();
		$instance['space_px'] = ( ! empty( $new_instance['space_px'] ) ) ? strip_tags( $new_instance['space_px'] ) : '';
		return $instance;
	}
}

// Register and load the widget
function wpb_load_widget() {
    register_widget( 'spacer_widget' );
}
add_action( 'widgets_init', 'wpb_load_widget' );