/**
  * Initialization of the class
  *
  * @return void
  */
 protected function init()
 {
     // Setting backPath
     $this->backPath = $GLOBALS['BACK_PATH'];
     // Setting GPvars:
     $this->cMR = (bool) GeneralUtility::_GP('cMR');
     $this->currentSubScript = GeneralUtility::_GP('currentSubScript');
     $this->setTempDBmount = GeneralUtility::_GP('setTempDBmount');
     // Create page tree object:
     $beUser = $this->getBackendUser();
     $this->pagetree = GeneralUtility::makeInstance(PageTreeView::class);
     $this->pagetree->ext_IconMode = $beUser->getTSConfigVal('options.pageTree.disableIconLinkToContextmenu');
     $this->pagetree->ext_showPageId = $beUser->getTSConfigVal('options.pageTree.showPageIdWithTitle');
     $this->pagetree->ext_showNavTitle = $beUser->getTSConfigVal('options.pageTree.showNavTitle');
     $this->pagetree->ext_separateNotinmenuPages = $beUser->getTSConfigVal('options.pageTree.separateNotinmenuPages');
     $this->pagetree->ext_alphasortNotinmenuPages = $beUser->getTSConfigVal('options.pageTree.alphasortNotinmenuPages');
     $this->pagetree->thisScript = 'alt_db_navframe.php';
     $this->pagetree->addField('alias');
     $this->pagetree->addField('shortcut');
     $this->pagetree->addField('shortcut_mode');
     $this->pagetree->addField('mount_pid');
     $this->pagetree->addField('mount_pid_ol');
     $this->pagetree->addField('url');
     // Temporary DB mounts:
     $this->initializeTemporaryDBmount();
 }