Add Custom Options for Widgets

_Add custom option for widgets.md

##Add Custom Options for WordPress Widgets This snippet will add some option to all registered widget in wordpress.

functions.php

<?php

  // Add New Options for All Registered widgets
  function add_widget_visibility_options( $widget, $return, $instance ) {
 
    $visible_desktop = isset( $instance['visible_desktop'] ) ? $instance['visible_desktop'] : 'on';
    $visible_mobile = isset( $instance['visible_mobile'] ) ? $instance['visible_mobile'] : 'on';
    
    ?>
    	<hr>
    	<strong>Widget Visibility</strong>
        <p>
            <input class="checkbox" type="checkbox" id="<?php echo $widget->get_field_id('visible_desktop'); ?>" name="<?php echo $widget->get_field_name('visible_desktop'); ?>" <?php echo (!empty($visible_desktop)) ? "checked":""; ?> />
            <label for="<?php echo $widget->get_field_id('visible_desktop'); ?>">Visible Desktop</label>
        </p>
        <p>
            <input class="checkbox" type="checkbox" id="<?php echo $widget->get_field_id('visible_mobile'); ?>" name="<?php echo $widget->get_field_name('visible_mobile'); ?>" <?php  echo (!empty($visible_mobile)) ? "checked":""; ?> />
            <label for="<?php echo $widget->get_field_id('visible_mobile'); ?>">Visible Mobile</label>
        </p>
    
		
    <?php

}
add_filter('in_widget_form', 'add_widget_visibility_options', 10, 3 );


// Add Save handle for the options
function save_widget_visibility_options( $instance, $new_instance ) {
 
  $new_instance['visible_desktop'] = ( !empty( $new_instance['visible_desktop'] ) ) ? $new_instance['visible_desktop']: '';
	$new_instance['visible_mobile'] = ( !empty( $new_instance['visible_mobile'] ) ) ? $new_instance['visible_mobile']: '';
 
  return $new_instance;
}
add_filter( 'widget_update_callback', 'save_widget_visibility_options', 10, 2 );


// In this case, it's add new classes to before_widget arg
function add_widget_visibility_classes( $params ) {
	global $wp_registered_widgets;
	$widget_id	= $params[0]['widget_id'];
	$widget_obj	= $wp_registered_widgets[$widget_id];
	$widget_opt	= get_option($widget_obj['callback'][0]->option_name);
	$widget_num	= $widget_obj['params'][0]['number'];

	$visibility = array(
		"visibility",
		(isset($widget_opt[$widget_num]['visible_desktop']) && !empty($widget_opt[$widget_num]['visible_desktop']) ) ? "visible-desktop":"",
		(isset($widget_opt[$widget_num]['visible_mobile']) && !empty($widget_opt[$widget_num]['visible_mobile'])) ? "visible-mobile":"",
	);

	
	$params[0]['before_widget'] = preg_replace(
		'/class="/',
		sprintf( 'class="%s ', implode(" ",$visibility) ),
		$params[0]['before_widget'],
		1
	);

	return $params;
}
add_filter( 'dynamic_sidebar_params', 'add_widget_visibility_classes' );

Great