User TCA types and bidirectional MM tables¶

Table of Contents¶

User TCA types and bidirectional MM tables 1

Introduction 1

Installation 2

Developers section 2

Configuration (bidirectional) 3

Tutorial 3

Known problems 5

To-Do list 5

Changelog 5

Introduction¶

Installation¶

There's nothing special to mention for installation, but the extension installs three XCLASSes the administrator should know about:

• t3lib/class.t3lib_transferdata.php
• t3lib/class.t3lib_tcemain.php

Using XCLASS is a way of changing core functions with an extension. This can work without problems but shouldn't be used generally and is more like a workaround.

When another extension installs an XCLASS for one of the mentioned files the whole functionality will break and database relations might be lost.

In a previous version of this extension the bidirectional functionality was patched (XCLASS) directly into the TYPO3 core. Now the changes made by the XCLASSes are very small in comparison. That means the default behavior of TCE shouldn't be affected in any way.

During installation one can choose to use the old XCLASSes which is deprecated!

Developers section¶

As said the extension provide an interface to allow the implementation of new TCE field types. An example implementation is included. A full documentation of the functionality can't be provided as it just too much to cover all topics. So this just an introduction.

Implementing a field type for TCE means to provide functions for converting data from the database for usage in backend forms (TCEforms) and converting the submitted form data for database storage or even write the data to the database.

In principle that can be done with a 'user' type in TCA and a user function for form rendering. But this will not work when database relations needs to be handled because the form data will be written to db as it is by TCE. That's where we need own functions when the default TCE fields don't provide the needed functionality.

To activate a so called userProcessClass for a field you have to add an entry in TCA like following:

'config' => array (
     'userProcessClass' => 'EXT:mmforeign/class.tx_mmforeign_tce.php:tx_mmforeign_tce',

A userProcessClass can (but don't must) provide following methods:

renderRecord_procField()
checkValue()
copyRecord_procField()
remapListedDBRecords_procField()

For details have a look into the example implementation. The methods have similar names like the methods in TCEmain so it is possible to have a look into the core how field handling work there.

Implementing all methods might not be needed, it depends on the data format (releations) and what's needed. For example renderRecord_procField() could be excluded when the data format coming from the database is already in expected format or a needed transformation will be done in a TCEforms user function.

When a method is not implemented the data will be passed through, which means it will not be touched by another TCE function.

Another example could be that only form data processing is wanted. Then checkValue() have to be implemented.

Configuration (bidirectional)¶

To enable the bidirectional MM handling for a field add in the TCA config section of the field:

"userProcessClass" => "EXT:mmforeign/class.tx_mmforeign_tce.php:tx_mmforeign_tce",

The extension works by extending the way you configure MM relations in the TCA for fields of type “select” and “group”.

'MM_match_fields' => array('ident' => 'category'),

'MM_insert_fields' => array('a_field' => 'a value'),

Tutorial¶

#
# Table structure for table 'tt_news_cat'
#
CREATE TABLE tt_news_cat (
        tx_mmforeignexample_tt_news int(11) DEFAULT '0' NOT NULL
);

 0: <?php
 1: if (!defined ('TYPO3_MODE'))     die ('Access denied.');
 2: $tempColumns = Array (
 3:     "tx_bidirectionalexample_tt_news" => Array (
 4:         "exclude" => 1,
 5:         "label" => "News in this category",
 6:         "config" => Array (
 7:             "type" => "select",
 8:             "userProcessClass" => "EXT:mmforeign/class.tx_mmforeign_tce.php:tx_mmforeign_tce",
 9:             "foreign_table" => "tt_news",
10:             "foreign_table_where" => "ORDER BY tt_news.crdate",
11:             "size" => 10,
12:             "minitems" => 0,
13:             "maxitems" => 100,
14:             "MM" => "tt_news_cat_mm",
15:             "MM_foreign_select" => 1,
16:         )
17:     ),
18: );
19: t3lib_div::loadTCA("tt_news_cat");
20: t3lib_extMgm::addTCAcolumns("tt_news_cat",$tempColumns,1);
21: t3lib_extMgm::addToAllTCAtypes("tt_news_cat","tx_mmforeignexample_tt_news;;;;1-1-1");
22: ?>

#
# Table structure for table 'tx_example_item_mm'
#
CREATE TABLE tx_example_item_mm (
  uid_local int(11) DEFAULT '0' NOT NULL,
  uid_foreign int(11) DEFAULT '0' NOT NULL,
  tablenames varchar(30) DEFAULT '' NOT NULL,
  ident varchar(30) DEFAULT '' NOT NULL,
  sorting int(11) unsigned DEFAULT '0' NOT NULL,
  KEY uid_local (uid_local),
  KEY uid_foreign (uid_foreign)
);

$TCA['tx_example_item'] = array(
...
        'columns' => array(
                'category' => array(
                        'label' => 'Category:',
                        'config' => array (
                                'type' => 'group',
                             'userProcessClass' => 'EXT:mmforeign/class.tx_mmforeign_tce.php:tx_mmforeign_tce',
                                'internal_type' => 'db',
                             'allowed' => 'tx_example_category',
                             'prepend_tname' => 1,
                             'MM' => 'tx_example_item_mm',
                             'MM_match_fields' => array('ident' => 'category'),
                                'size' => 3,
                                'maxitems' => 200,
                                'minitems' => 0,
                        )
                ),

$TCA['tx_example_category'] = array(
...
        'columns' => array(
                'related' => array(
                        'label' => 'Category:',
                        'config' => array (
                                'type' => 'group',
                             'userProcessClass' => 'EXT:mmforeign/class.tx_mmforeign_tce.php:tx_mmforeign_tce',
                                'internal_type' => 'db',
                             'allowed' => 'tx_example_item',
                             'prepend_tname' => 1,
                             'MM' => 'tx_example_item_mm',
                             'MM_foreign_select' => 1,
                             'MM_match_fields' => array('ident' => 'category'),
                                'size' => 3,
                                'maxitems' => 200,
                                'minitems' => 0,
                        )
                ),

Known problems¶

To-Do list¶

- Find somebody who will make this part of the core.

Changelog¶

- Implemented an interface in TCEmain and make 'bidirectional' use of it. Much cleaner.

User TCA types and bidirectional MM tables - 5