The default controller for extension and plugin can not be determined ERROR in TYPO3

Question

I built an extension and I would like to add plugin options at the time of adding the plugin to the page

 Extension Name : hotels

in Hotel

Answer 1

Try it.

in ext_localconf.php

\TYPO3\CMS\Extbase\Utility\ExtensionUtility::configurePlugin(
    'TYPO3.' . $_EXTKEY,
    'hotels',
    array(
        'Hotel' => 'list,single,display,update,save,preview,edit'
    ),
    // non-cacheable actions
    array(
        'Hotel' => 'list',
    )
);

in ext_tables.php

\TYPO3\CMS\Extbase\Utility\ExtensionUtility::registerPlugin(
    $_EXTKEY,
    'hotels',
    'list of Hotels'
);

$extensionName  = \TYPO3\CMS\Core\Utility\GeneralUtility::underscoredToUpperCamelCase($_EXTKEY);
$pluginSignature = strtolower($extensionName). '_hotels';


if (TYPO3_MODE === 'BE') {

    /**
     * Registers a Backend Module
     */
    \TYPO3\CMS\Extbase\Utility\ExtensionUtility::registerModule(
        'TYPO3.' . $_EXTKEY,
        'web',   // Make module a submodule of 'web'
        'hotels',   // Submodule key
        '',                     // Position
        array(
            'Hotel' => 'list,single,display,update,save,preview,edit'
        ),
        array(
            'access' => 'user,group',
            'icon'   => 'EXT:' . $_EXTKEY . '/ext_icon.gif',
            'labels' => 'LLL:EXT:' . $_EXTKEY . '/Resources/Private/Language/locallang_hotels.xlf',
        )
    );

}

\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addStaticFile($_EXTKEY, 'Configuration/TypoScript', 'Hotels List');

@Clear cache and remove typo3temp data

Answer 2

In TYPO3 6.x, you are advised to use namespaced classes and tell the configurePlugin method your vendor name.

As you didnt include any of your controller code, I'll try to sketch it:

1. At first, make sure, you use a namespaced controller class-remember to set a Vendor name.
2. Make sure, your actions are named with the *Action suffix

EXT: myext/Classes/Controller/HotelController

namespace MyVendor\MyExt\Controller;
class HotelController {
    /**
    * @return void
    */
     public function listAction(){
     }
}

Next, mention the namespace in configurePlugin like this:

\TYPO3\CMS\Extbase\Utility\ExtensionUtility::configurePlugin(
    'MyVendor.' . $_EXTKEY,
    // UpperCamelCase please, refer to [1]
    'Hotels',
     array('Hotel' => 'list,single,display,update,save,preview,edit')
);

This allows the class locator to resolve the classes correctly.

To verify it, make sure you re-install your extension.

PS: Please use the namespaced classes whenever possible in 6.x. The old Tx_* classes are only aliases and put additional load on your interpreter.

1 - TYPO3 API Docs for ExtensionUtility::configurePlugin()

Update:

There is a multitude of possible errors.

1. You wired a FlexForm. Did you set the switchableControllerActions appropriately?
2. One thing I saw more than once: The f:link.action (or f:uri.action respectively) doesnt like to be without an appropriate controller attribute
3. You clearly missed the namespace concept :) Rename your ControllerClass to HotelController and the file must live in Classes/Controller/HotelController.php, then do the adjustments to configurePlugin() to reflect the vendorName as I described