Method 4: Customized Recent_Posts widget class Full tutorial: http://www.rvamedia.com/wordpress/customize-wordpress-widget-title

custom_widgets.php

<?php

/**
 * Recent_Posts widget class
 *
 * @since 2.8.0
 */
class WP_Widget_Recent_Posts_Custom extends WP_Widget_Recent_Posts {

    function __construct() {
		$widget_ops = array('classname' => 'widget_recent_entries', 'description' => __( "The most recent posts on your site") );
		parent::__construct('recent-posts', __('Recent Posts'), $widget_ops);
		$this->alt_option_name = 'widget_recent_entries';

		add_action( 'save_post', array($this, 'flush_widget_cache') );
		add_action( 'deleted_post', array($this, 'flush_widget_cache') );
		add_action( 'switch_theme', array($this, 'flush_widget_cache') );
	}

	function widget($args, $instance) {
		$cache = wp_cache_get('widget_recent_posts', 'widget');

		if ( !is_array($cache) )
			$cache = array();

		if ( ! isset( $args['widget_id'] ) )
			$args['widget_id'] = $this->id;

		if ( isset( $cache[ $args['widget_id'] ] ) ) {
			echo $cache[ $args['widget_id'] ];
			return;
		}

		ob_start();
		extract($args);

		$title = apply_filters('widget_title', empty($instance['title']) ? __('Recent Posts') : $instance['title'], $instance, $this->id_base);
		if ( empty( $instance['number'] ) || ! $number = absint( $instance['number'] ) )
 			$number = 10;
		$show_date = isset( $instance['show_date'] ) ? $instance['show_date'] : false;

		$r = new WP_Query( apply_filters( 'widget_posts_args', array( 'posts_per_page' => $number, 'no_found_rows' => true, 'post_status' => 'publish', 'ignore_sticky_posts' => true ) ) );
		if ($r->have_posts()) :
?>
		<?php echo $before_widget; ?>
		<?php if ( $title ) echo $before_title . html_entity_decode($title) . $after_title; ?>
		<ul>
		<?php while ( $r->have_posts() ) : $r->the_post(); ?>
			<li>
				<a href="<?php the_permalink() ?>" title="<?php echo esc_attr( get_the_title() ? get_the_title() : get_the_ID() ); ?>"><?php if ( get_the_title() ) the_title(); else the_ID(); ?></a>
			<?php if ( $show_date ) : ?>
				<span class="post-date"><?php echo get_the_date(); ?></span>
			<?php endif; ?>
			</li>
		<?php endwhile; ?>
		</ul>
		<?php echo $after_widget; ?>
<?php
		// Reset the global $the_post as this query will have stomped on it
		wp_reset_postdata();

		endif;

		$cache[$args['widget_id']] = ob_get_flush();
		wp_cache_set('widget_recent_posts', $cache, 'widget');
	}

	function update( $new_instance, $old_instance ) {
		$instance = $old_instance;

		//WPSYNTAX: $instance['title'] = strip_tags($new_instance['title']);
		if (current_user_can('unfiltered_html')){
     		$instance['title'] = $new_instance['title'];
		}
		else {
     		strip_tags($new_instance['title']);
		}


		$instance['number'] = (int) $new_instance['number'];
		$instance['show_date'] = (bool) $new_instance['show_date'];
		$this->flush_widget_cache();

		$alloptions = wp_cache_get( 'alloptions', 'options' );
		if ( isset($alloptions['widget_recent_entries']) )
			delete_option('widget_recent_entries');

		return $instance;
	}

	function flush_widget_cache() {
		wp_cache_delete('widget_recent_posts', 'widget');
	}

	function form( $instance ) {
		$title     = isset( $instance['title'] ) ? esc_attr( $instance['title'] ) : '';
		$number    = isset( $instance['number'] ) ? absint( $instance['number'] ) : 5;
		$show_date = isset( $instance['show_date'] ) ? (bool) $instance['show_date'] : false;
?>
		<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 $title; ?>" /></p>

		<p><label for="<?php echo $this->get_field_id( 'number' ); ?>"><?php _e( 'Number of posts to show:' ); ?></label>
		<input id="<?php echo $this->get_field_id( 'number' ); ?>" name="<?php echo $this->get_field_name( 'number' ); ?>" type="text" value="<?php echo $number; ?>" size="3" /></p>

		<p><input class="checkbox" type="checkbox" <?php checked( $show_date ); ?> id="<?php echo $this->get_field_id( 'show_date' ); ?>" name="<?php echo $this->get_field_name( 'show_date' ); ?>" />
		<label for="<?php echo $this->get_field_id( 'show_date' ); ?>"><?php _e( 'Display post date?' ); ?></label></p>
<?php
	}
}




/**
 * Text widget class
 *
 * @since 2.8.0
 */
class WP_Widget_Text_Custom extends WP_Widget_Text {

	function __construct() {
		$widget_ops = array('classname' => 'widget_text', 'description' => __('Arbitrary text or HTML'));
		$control_ops = array('width' => 400, 'height' => 350);
		parent::__construct('text', __('Text'), $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 );
		echo $before_widget;
		if ( !empty( $title ) ) { echo $before_title . html_entity_decode($title) . $after_title; } ?>
			<div class="textwidget"><?php echo !empty( $instance['filter'] ) ? wpautop( $text ) : $text; ?></div>
		<?php
		echo $after_widget;
	}

	function update( $new_instance, $old_instance ) {
		$instance = $old_instance;
		//WPSyntax: $instance['title'] = strip_tags($new_instance['title']);
		
		if (current_user_can('unfiltered_html')){
     		$instance['title'] = $new_instance['title'];
		}
		else {
     		strip_tags($new_instance['title']);
		}
		
		
		
		if ( current_user_can('unfiltered_html') )
			$instance['text'] =  $new_instance['text'];
		else
			$instance['text'] = stripslashes( wp_filter_post_kses( addslashes($new_instance['text']) ) ); // wp_filter_post_kses() expects slashed
		$instance['filter'] = isset($new_instance['filter']);
		return $instance;
	}

	function form( $instance ) {
		$instance = wp_parse_args( (array) $instance, array( 'title' => '', 'text' => '' ) );
		//$title = strip_tags($instance['title']);
		$title = $instance['title'];
		$text = esc_textarea($instance['text']);
?>
		<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>

		<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); ?> />&nbsp;<label for="<?php echo $this->get_field_id('filter'); ?>"><?php _e('Automatically add paragraphs'); ?></label></p>
<?php
	}
}

i use this cod in دانلود آهنگ جدید