How to use/link sys_category field in custom model in TYPO3

Question

I am developing an extension in which I am uploading files and for each file upload I need to have one or more categories associated with it.

I have built a custom category model and it shows fine at the backend when creating a record, but I want to show/link the sys_category records instead of my own custom categories.

How do I link that field in my custom model?

Answer 1

If anyone else stumbles upon this, I found the solution from the documentation thanks to @larry-pete.

Simply add these lines to your ext_tables.php file in your extension folder.

// Add an extra categories selection field to the pages table
    \TYPO3\CMS\Core\Utility\ExtensionManagementUtility::makeCategorizable(
        'ext_key',
        'your_table_name',
        'categories',
        array(
            // Set a custom label
            'label' => 'LLL:EXT:ext_key/Resources/Private/Language/locallang.xlf:additional_categories',
            // This field should not be an exclude-field
            'exclude' => FALSE,
            // Override generic configuration, e.g. sort by title rather than by sorting
            'fieldConfiguration' => array(
                'foreign_table_where' => ' AND sys_category.sys_language_uid IN (-1, 0) ORDER BY sys_category.title ASC',
            ),
            // string (keyword), see TCA reference for details
            'l10n_mode' => 'exclude',
            // list of keywords, see TCA reference for details
            'l10n_display' => 'hideDiff',
        )
    );

Hope it helps someone.