Widget Function

This Widget function is used to display the Widget on the page.

First we start off by getting the values from the database so we know what information we need to get from Twitter. To get the values from the database we use the second parameter in the widget function.

/* Our variables from the widget settings. */
$this->twitter_title = apply_filters(‘widget_title’, $instance[‘title’] );
$this->twitter_username = $instance[‘username’];
$this->twitter_postcode = $instance[‘postcount’];
$this->twitter_follow_text = $instance[‘tweettext’];

The problem with using the Twitter API is that there is a limit on the amount of requests you get do per hour. This currently stands at 150 requests per hour, so if your website gets more than 150 page views an hour you will need to cache the Twitter results to use in the widget.

WordPress comes with an easy way to store bits of code as a temporary caching, this uses the Transient API by using the get and set transient functions.

Get Transient

The get_transient function will return the cached value for the provided transient name.
< ?php get_transient( $transient_name ); ?>

Set Transient

The set_transient function will set cache in WordPress by supplying the transient name, value to be cached and how long you want it be cached.
< ?php set_transient( $transient_name, $value, $expiration ); ?>

Below is the code we use to cache the tweets from your user stream. This first checks to see if there is anything stored in the cache, if it isn’t then it will call the Twitter API to get the new tweets.
$transName = ‘list-tweets’; // Name of value in database.
$cacheTime = 10; // Time in minutes between updates.
if(false === ($twitterData = get_transient($transName) ) ){
// Get the tweets from Twitter.
$json = wp_remote_get(«http://api.twitter.com/1/statuses/user_timeline.json?screen_name=».$this->twitter_username.»&count=».$this->twitter_postcode);
// Get tweets into an array.
$twitterData = json_decode($json[‘body’], true);
// Save our new transient.
set_transient($transName, $twitterData, 60 * $cacheTime);
}

Now we have the Twitter stream we can display these on the website. We do this by looping through each of the tweets and add them to a list item which we can echo at the end to display all the tweets.

Here is the whole code to display the tweets.

/**
* 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 ) {
extract( $args );
/* Our variables from the widget settings. */
$this->twitter_title = apply_filters(‘widget_title’, $instance[‘title’] );
$this->twitter_username = $instance[‘username’];
$this->twitter_postcode = $instance[‘postcount’];
$this->twitter_follow_text = $instance[‘tweettext’];
$transName = ‘list-tweets’; // Name of value in database.
$cacheTime = 10; // Time in minutes between updates.
if(false === ($twitterData = get_transient($transName) ) ){
// Get the tweets from Twitter.
$json = wp_remote_get(«http://api.twitter.com/1/statuses/user_timeline.json?screen_name=».$this->twitter_username.»&count=».$this->twitter_postcode);
// Get tweets into an array.
$twitterData = json_decode($json[‘body’], true);
// Save our new transient.
set_transient($transName, $twitterData, 60 * $cacheTime);
}
/* Before widget (defined by themes). */
echo $before_widget;
?>

< ?php /* After widget (defined by themes). */ echo $after_widget; } /** * Find links and create the hyperlinks */ private function hyperlinks($text) { $text = preg_replace('/\b([a-zA-Z]+:\/\/[\w_.\-]+\.[a-zA-Z]{2,6}[\/\w\-~.?=&%#+$*!]*)\b/i',"$1″, $text);
$text = preg_replace(‘/\b(?< !:\/\/)(www\.[\w_.\-]+\.[a-zA-Z]{2,6}[\/\w\-~.?=&%#+$*!]*)\b/i',"$1″, $text);
// match name@address
$text = preg_replace(«/\b([a-zA-Z][a-zA-Z0-9\_\.\-]*[a-zA-Z]*\@[a-zA-Z][a-zA-Z0-9\_\.\-]*[a-zA-Z]{2,6})\b/i»,»$1«, $text);
//mach #trendingtopics. Props to Michael Voigt
$text = preg_replace(‘/([\.|\,|\:|\¡|\¿|\>|\{|\(]?)#{1}(\w*)([\.|\,|\:|\!|\?|\>|\}|\)]?)\s/i’, «$1#$2$3 «, $text);
return $text;
}
/**
* Find twitter usernames and link to them
*/
private function twitter_users($text) {
$text = preg_replace(‘/([\.|\,|\:|\¡|\¿|\>|\{|\(]?)@{1}(\w*)([\.|\,|\:|\!|\?|\>|\}|\)]?)\s/i’, «$1@$2$3 «, $text);
return $text;
}
Update Function

The update function is used to add the values of the widget dashboard to the database so we can use this when displaying the Widget.

For this function we are just going to loop through all the inputs from the form and strip all tags from the input boxes. Now we can just return a validated array and these are the values which are added to the database.

/**
* 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.
*/
function update( $new_instance, $old_instance ) {
$instance = $old_instance;
// Strip tags to remove HTML (important for text inputs)
foreach($new_instance as $k => $v){
$instance[$k] = strip_tags($v);
}
return $instance;
}
Form Function

The form function is used on the widgets dashboard screen and will allow you to edit data in the plugin.

From this form we want to change the title of the widget, the Twitter username, the amount of tweets to display and the follow me text.

/**
* Create the form for the Widget admin
*
* @see WP_Widget::form()
*
* @param array $instance Previously saved values from database.
*/
function form( $instance ) {
/* Set up some default widget settings. */
$defaults = array(
‘title’ => $this->twitter_title,
‘username’ => $this->twitter_username,
‘postcount’ => $this->twitter_postcode,
‘tweettext’ => $this->twitter_follow_text,
);
$instance = wp_parse_args( (array) $instance, $defaults ); ?>

get_field_id( ‘username’ ); ?>»>< ?php _e('Twitter Username e.g. paulund_', 'framework') ?>
get_field_id( ‘postcount’ ); ?>»>< ?php _e('Number of tweets (max 20)', 'framework') ?>
get_field_id( ‘tweettext’ ); ?>»>< ?php _e('Follow Text e.g. Follow me on Twitter', 'framework') ?>