Adding field type for terms or categories - a kind of related type

field_types/term_field/term_field.php

@@ -0,0 +1,96 @@
+<?php
+// initialisation
+global $mf_domain;
+
+// class with static properties encapsulating functions for the field type
+
+class term_field extends mf_custom_fields {
+
+  public $allow_multiple = TRUE;
+  public $has_properties = TRUE;
+
+  public function _update_description(){
+    global $mf_domain;
+    $this->description = __("This field allows to do relations with taxonomie terms",$mf_domain);
+  }
+
+  public function _options(){
+    global $mf_domain;
+
+	// Get the taxonomie as dropdownoption
+	$select = array();
+	$zahl = 0;
+	$tax = get_taxonomies();
+	foreach($tax as $k => $v){
+		$select[$zahl++] = $v;
+	 }
+
+    $data = array(
+     'option'  => array(
+        'term'  => array(
+          'type'        =>  'select',
+          'id'          =>  'term',
+          'label'       =>  __('related taxonomie: ',$mf_domain),
+          'name'        =>  'mf_field[option][term]',
+          'default'     =>  '',
+          'options'     => $select,
+          'add_empty'   => false,
+          'description' =>  '',
+          'value'       =>  '',
+          'div_class'   => '',
+          'class'       => ''
+        ),
+      )
+    );
+    return $data;
+
+  }
+
+
+  public function display_field( $field, $group_index = 1, $field_index = 1 ) {
+    global $mf_domain;
+
+    // If is not required this field be added a None value
+    $notype = "";
+    if( !$field['required_field'] ) {
+      $notype = ( !empty($field['options']['notype']) ) ? $field['options']['notype'] : __( "-- None --" , $mf_domain );
+    }
+
+    $output = '';
+
+	// Get the taxonomie as dropdownoption
+	$select = array();
+	$zahl = 0;
+	$tax = get_taxonomies();
+	foreach($tax as $k => $v){
+		$select[$zahl++] = $v;
+	 }
+
+	$option_from_term_array = $field['options']['term'];
+	$options = get_terms($select[$option_from_term_array]);
+
+    $output = '<div class="mf-dropdown-box">';
+
+  	$value = $field['input_value'];
+
+    $output .= sprintf('<select class="dropdown_mf" id="%s" name="%s" >',$field['input_id'],$field['input_name']);
+
+    if( $notype != "" ) {
+      $output .= "<option value=''>$notype</option>";
+    }
+
+    foreach($options as $option) {
+
+      $check = ($option->slug == $value) ? 'selected="selected"' : '';
+      $output .= sprintf('<option value="%s" %s >%s</option>',
+        esc_attr($option->slug),
+        $check,
+        esc_attr($option->name)
+      );
+    }
+    $output .= '</select>';
+    $output .= '</div>';
+
+    return $output;
+  }
+}