可切换控制器动作中的元素在TYPO3中没有被FlexForm显示

我有问题弄清楚我的可切换控制器动作是什么问题。

我用的是TYPO3 v7.6.10

extentionkey/Configuration/TCA/Overrides/tt_content.php中的条目:

$pluginSignature = 'simpleblog_bloglisting';
$GLOBALS['TCA']['tt_content']['types']['list']['subtypes_addlist'][$pluginSignature] = 'pi_flexform';
'TYPO3'CMS'Core'Utility'ExtensionManagementUtility::addPiFlexFormValue($pluginSignature, 'FILE:EXT:simpleblog/Configuration/FlexForms/FF_Simpleblog_Bloglisting.xml' );

extentionkey/配置/柠檬酸/FlexForms/FF_Simpleblog_Bloglisting.xml:

<T3DataStructure>
    <sheets>
        <sDEF>
            <ROOT>
                <TCEforms>
                    <sheetTitle>Blog Config</sheetTitle>
                </TCEforms>
                <type>array</type>
                <el>
                    <settings.blog.max>
                        <TCEforms>
                            <label>Max number of Blogs</label>
                            <config>
                                <type>input</type>
                                <size>2</size>
                                <eval>int</eval>
                                <default>4</default>
                            </config>
                        </TCEforms>
                    </settings.blog.max>
                    <settings.blog.min>
                        <TCEforms>
                            <label>Page Browser</label>
                            <config>
                                <type>group</type>
                                <internal_type>db</internal_type>
                                <allowed>pages</allowed>
                                <size>1</size>
                                <maxitems>1</maxitems>
                                <minitems>0</minitems>
                                <show_thumbs>1</show_thumbs>
                            </config>
                        </TCEforms>
                    </settings.blog.min>
                    <switchableControllerActions>
                        <TCEForms>
                            <label>Type</label>
                            <config>
                                <type>select</type>
                                <items type="array">
                                    <numIndex index="0" type="array">
                                        <numIndex index="0">read only</numIndex>
                                        <numIndex index="1">Blog->list;Blog->show</numIndex>
                                    </numIndex>
                                    <numIndex index="1" type="array">
                                        <numIndex index="0">writable</numIndex>
                                        <numIndex index="1">Blog->list;Blog->show;Blog->deleteConfirm;Blog->delete</numIndex>
                                    </numIndex>
                                </items>
                            </config>
                        </TCEForms>
                    </switchableControllerActions>
                </el>
            </ROOT>
        </sDEF>
    </sheets>
</T3DataStructure>

显示<settings.blog.max>标签中的元素，但不显示</switchableControllerActions>标签中的元素