我正在编写一个插件，它定义了一个要多次调用的类。该类使用add_action 将它自己的方法注册为回调。
class MyClass {
__construct($foo) {
add_action(\'hook1\', array($this, \'method1\') );
add_action(\'hook2\', array($this, \'method2\') );
}
public function method1() {...}
public function method2() {...}
}
这很好用。但当我做两次时，只有第二次起作用。
new MyClass(\'foo\');
new MyClass(\'bar\');
换句话说，上述代码的结果正是我从以下内容中所期望的结果：
// new MyClass(\'foo\');
new MyClass(\'bar\');
似乎第二个实例覆盖了第一个实例。我做错了什么？
我已经检查过了spl_object_hash() 这两种情况都是不同的。
我补充道var_dump($wp_filter); 在我的代码之后，我看到这两个实例都列在相关的操作挂钩键下。所以看起来WP知道他们都在那里。。。
Full code from my complete plugin:
将其粘贴到/wp-content/mu-plugins中的文件中。然后添加/编辑帖子。你
should 可以看到两个新的自定义元框“Foo”和“Bar”，但只能看到“Bar”。注释最后一行，以使用类实例的不同组合进行测试。
<?php
/*
Plugin Name: SDP Custom Meta Boxes
Description: Defines a custom meta box framework class.
*/
class SDP_Custom_Field {
public $name = NULL;
public $slug = NULL;
public $prefix = NULL;
public $post_type = \'post\'; //The type of Write screen on which to show the meta: \'post\', \'page\', \'dashboard\', \'link\', \'attachment\' or \'custom_post_type\'
public $meta_box_location = \'normal\'; //\'normal\', \'advanced\', or \'side\'
public $meta_box_priority = \'default\'; //\'high\', \'core\', \'default\' or \'low\'
public $meta_box_field_type = NULL;
public function __construct( $custom_field_name, $args=array() ) {
#set the name
$this->name = $custom_field_name;
#set the slug
if (isset($args[\'slug\'])) {
$this->slug = $args[\'slug\'];
} else {
$slug = strtolower($custom_field_name);
$slug = str_replace(\' \', \'_\', $slug);
$this->slug = $slug;
}
#set the meta_box_field_type
if (isset($args[\'field_type\'])) {
switch ($args[\'field_type\']) {
case \'text\':
$this->meta_box_field_type = \'text\';
break;
case \'textarea\':
$this->meta_box_field_type = \'textarea\';
break;
default:
$this->meta_box_field_type = \'text\';
break;
}
} else {
$this->meta_box_field_type = \'text\';
}
// add_action( \'add_meta_boxes\', array($this, \'_add_custom_metaboxes\'));
// add_action( \'save_post\', array($this, \'_save_postdata\'));
add_action( \'add_meta_boxes\', array(&$this, \'_add_custom_metaboxes\'));
add_action( \'save_post\', array(&$this, \'_save_postdata\'));
//var_dump( is_object( array($this, \'_add_custom_metaboxes\') ));
}
// public function go() {
// add_action( \'add_meta_boxes\', array($this, \'_add_custom_metaboxes\'));
// add_action( \'save_post\', array($this, \'_save_postdata\'));
// }
#Echo the HTML for this meta box...
public function _print_field_HTML( $post ) {
$value = get_post_meta( $post->ID, $this->slug, true );
// Add an nonce field so we can check for it later.
wp_nonce_field( $this->slug.\'_custom_box\', $this->slug.\'_custom_box_nonce\' );
echo \'<label for="\'.$this->slug.\'">\'.$this->name.\'</label> \';
echo \'<input type="text" id="\'.$this->slug.\'" name="\'.$this->slug.\'" value="\' . esc_attr( $value ) . \'" size="25" />\';
//TODO: Add update button
//TODO: Add delet button
}
public function _add_custom_metaboxes() {
#http://codex.wordpress.org/Function_Reference/add_meta_box
add_meta_box( NULL, $this->name, array(&$this, \'_print_field_HTML\'), $this->post_type, $this->meta_box_location, $this->meta_box_priority, NULL );
}
/**
* When the post is saved, saves our custom data.
* @param int $post_id The ID of the post being saved.
*/
public function _save_postdata( $post_id ) {
/*
* We need to verify this came from the our screen and with proper authorization,
* because save_post can be triggered at other times.
*/
// Check if our nonce is set.
if ( ! isset( $_POST[$this->slug.\'_custom_box_nonce\'] ) )
return $post_id;
#http://codex.wordpress.org/Function_Reference/wp_nonce_field
$nonce = $_POST[$this->slug.\'_custom_box_nonce\'];
// Verify that the nonce is valid.
if ( ! wp_verify_nonce( $nonce, $this->slug.\'_custom_box\' ) )
return $post_id;
// If this is an autosave, our form has not been submitted, so we don\'t want to do anything.
if ( defined( \'DOING_AUTOSAVE\' ) && DOING_AUTOSAVE )
return $post_id;
if ( ! current_user_can( \'edit_post\', $post_id ) )
return $post_id;
/* OK, its safe for us to save the data now. */
// Sanitize user input.
$mydata = sanitize_text_field( $_POST[$this->slug] );
// Update the meta field in the database.
update_post_meta( $post_id, $this->slug, $mydata );
}
}
new SDP_Custom_Field( \'Foo\' );
new SDP_Custom_Field( \'Bar\' );
