Default or Calculated Dependee Attributes

ATK Howto: Default or Calculated Dependee Attributes Complexity: Easy Author: [Wayne H] wayne@hulls.net.nz

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Example code of how to create dependee attributes which can be defaulted to a calculated value and edited or always calauated and read only

class.testdeps.inc

<?php

 /**
 *
 * testdeps - test dependees
 *
 * attribute "number" can have any number entered
 * attributes "depnoedit" and depnoro" are BOT dependeess of attribute "number"
 * attribute "depnoedit" IF blank is set to a default value of half of attribute "number"
 *	attribute "depnoedit" is EDITABLE
 * attribute "depnoro" is always half of attribute "number" and is READ ONLY
 *
 * TABLE create SQL
 * CREATE TABLE `testdeps` (
 *	`pktestdep` INT(10) UNSIGNED NOT NULL DEFAULT '0',
 *	`number` INT(10) UNSIGNED NULL DEFAULT NULL,
 *	`depnoedit` INT(10) UNSIGNED NULL DEFAULT NULL,
 *	`depnoro` INT(10) UNSIGNED NULL DEFAULT NULL,
 *	PRIMARY KEY (`pktestdep`)
 *	)
 * COLLATE=utf8_general_ci
 * ENGINE=MyISAM
 * ROW_FORMAT=DYNAMIC
 * AVG_ROW_LENGTH=0
 */
 
 useattrib("atknumberattribute");

 class testdeps extends atkNode
 {
   function testdeps()
   {
     $this->atkNode("testdeps", NF_ADD_LINK|NF_ADDAFTERADD);

// Primary key

     $this->add(new atkAttribute("pktestdep", AF_AUTOINCREMENT|AF_PRIMARY|AF_HIDE));
     

// value for "number" can be entered $attr_number = &$this->add(new atkNumberAttribute("number"));

// Fields are dependent on "number"

     $attr_number->addDependee("depnoedit");
     $attr_number->addDependee("depnoro");

// If blank is set to a default value. Is always editable

     $attr_depnoedit = &$this->add(new atkNumberAttribute("depnoedit"));

// Is always calculated from "number" and is always READ ONLY

     $attr_depnoro = &$this->add(new atkNumberAttribute("depnoro",AF_READONLY));

$this->setOrder("pktestdep");

     $this->setIndex("pktestdep");	  

$this->setTable("testdeps");

   } // function testdeps

  // Override normal attribute edit
  function depnoedit_edit($record, $mode)
  {
     // Set default value IF attribute is empty

if ($record["depnoedit"]==) { $record["depnoedit"] = $record["number"] * 0.5; } // return editable value $attr = &$this->getAttribute("depnoedit");

       return $attr->edit($record, $mode); 

} //function

  // Overrode normal attribute display 	
  function depnoro_display($record, $mode)
  {
     // Calculate value of attribute "depnoro"

$record["depnoro"] = $record["number"] * 0.5;

// return displayable value $attr = &$this->getAttribute("depnoro");

     return $attr->display($record, $mode); 
  }
  
 } //Class

?>