# Customization Examples¶

Many extracts can be found throughout the manual, but this section provides more complete examples.

## Example 1: Extending the fe_users table¶

The “examples” extension adds two fields to the “fe_users” table. Here’s the complete code, taken from file Configuration/TCA/Overrides/fe_users.php:

<?php
defined('TYPO3_MODE') or die();

// Add some fields to fe_users table to show TCA fields definitions
[
'tx_examples_options' => [
'exclude' => 0,
'label' => 'LLL:EXT:examples/Resources/Private/Language/locallang_db.xlf:fe_users.tx_examples_options',
'config' => [
'type' => 'select',
'renderType' => 'selectSingle',
'items' => [
['',0,],
['LLL:EXT:examples/Resources/Private/Language/locallang_db.xlf:fe_users.tx_examples_options.I.0',1,],
['LLL:EXT:examples/Resources/Private/Language/locallang_db.xlf:fe_users.tx_examples_options.I.1',2,],
['LLL:EXT:examples/Resources/Private/Language/locallang_db.xlf:fe_users.tx_examples_options.I.2','--div--',],
['LLL:EXT:examples/Resources/Private/Language/locallang_db.xlf:fe_users.tx_examples_options.I.3',3,],
],
'size' => 1,
'maxitems' => 1,
],
],
'tx_examples_special' => [
'exclude' => 0,
'label' => 'LLL:EXT:examples/Resources/Private/Language/locallang_db.xlf:fe_users.tx_examples_special',
'config' => [
'type' => 'user',
// renderType needs to be registered in ext_localconf.php
'renderType' => 'specialField',
'parameters' => [
'size' => '30',
'color' => '#F49700',
],
],
],
]
);
'fe_users',
'tx_examples_options, tx_examples_special'
);


Note

The second example tx_examples_special only works when the renderType has been registered implemented and then registered in the ext_localconf.php. Please refer to the the following chapter of the TCA reference on how to implement it: t3tca:columns-user.

In the first statement the fields are added by calling ExtensionManagementUtility::addTCAcolumns()'. The first parameter is the name of the table to which the fields should be added. The second parameter is and array of the fields to be added. Each field is represented in the :ref:TCA syntax for columns <t3tca:columns>.

In the second statement the fields are added to the “types” definition of the “fe_users” table by calling ExtensionManagementUtility::addToAllTCAtypes(). The first parameter is the table name once more. The second parameter is a string, in the syntax as used in the showitem property of types in TCA. An optional third specify the position ('before' or 'after') in relation to an existing field. So you could call optionally:

\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addToAllTCAtypes(
'fe_users',
'tx_examples_options, tx_examples_special',
'',
);


If the third parameter is omitted ot the specified field not found, new fields are added at the bottom of the form. If the table uses tabs, new fields are added at the bottom of the Extended tab. This tab is created automatically if it does not exist.

Neither statement creates the corresponding fields in the database. The new fields must also be defined in the ext_tables.sql file of the extension:

CREATE TABLE fe_users (
tx_examples_options int(11) DEFAULT '0' NOT NULL,
tx_examples_special varchar(255) DEFAULT '' NOT NULL
);


Note

The above statement uses the SQL CREATE TABLE statement. This is the way TYPO3 expects it to be. The Extension Manager will automatically transform this into a ALTER TABLE statement when it detects that the table already exists.

The following screen shot shows the placement of the two new fields when editing a “fe_users” record:

The next example shows how to place a field more precisely.

## Example 2: Extending the tt_content Table¶

In the second example, we will add a “No print” field to all content element types. First of all, we add its SQL definition in ext_tables.sql:

CREATE TABLE tt_content (
tx_examples_noprint tinyint(4) DEFAULT '0' NOT NULL
);


Then we add it to the $GLOBALS['TCA'] in Configuration/TCA/Overrides/tt_content.php: \TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addTCAcolumns( 'tt_content', [ 'tx_examples_noprint' => [ 'exclude' => 0, 'label' => 'LLL:EXT:examples/Resources/Private/Language/locallang_db.xlf:tt_content.tx_examples_noprint', 'config' => [ 'type' => 'check', 'renderType' => 'checkboxToggle', 'items' => [ [ 0 => '', 1 => '' ] ], ], ], ] ); \TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addFieldsToPalette( 'tt_content', 'access', 'tx_examples_noprint', 'before:editlock' );  The code is mostly the same as in the first example, but the last statement is different and requires an explanation. The tables pages and tt\_content use palettes extensively. This increases flexibility. Therefore we call ExtensionManagementUtility::addFieldsToPalette() instead of ExtensionManagementUtility::addToAllTCAtypes(). We need to specify the palette’s key as the second argument (access). Precise placement of the new field is achieved with the fourth parameter (before:editlock). This will place the “no print” field right before the Restrict editing by non-Admins field, instead of putting it in the Extended tab. The result is the following: Note Obviously this new field will now magically exclude a content element from being printed. For it to have any effect, it must be used during the rendering by modifying the TypoScript used to render the “tt_content” table. Although this is outside the scope of this manual, here is an example of what you could do, for the sake of showing a complete process. Assuming you are using “fluid_styled_content” (which is installed by default), you could add the following TypoScript to your template: tt_content.stdWrap.outerWrap = <div class="noprint">|</div> tt_content.stdWrap.outerWrap.if.isTrue.field = tx_examples_noprint  This will wrap a “div” tag with a “noprint” class around any content element that has its “No print” checkbox checked. The final step would be to declare the appropriate selector in the print-media CSS file so that “noprint” elements don’t get displayed. This is just an example of how the effect of the “No print” checkbox can be ultimately implemented. It is meant to show that just adding the field to the $GLOBALS['TCA']` is not enough.