[Warning] ViewableData_Customised::obj() 'DetailForm' was requested from the array data as an object but it's not an object. I can't cast it.
POST /SilverStripe/admin/assets/EditForm/field/Files/ImportForm?ctf[Files][start]=0&ctf[Files][per_page]=10&ctf[Files][showall]=0&ctf[Files][sort]=SortOrder&ctf[Files][sort_dir]=DESC&ctf[Files][search]=&ctf[Files][filter]=&ctf[Files][view]=

Line 990 in /var/www/clients/client1/web1/web/SilverStripe/sapphire/core/ViewableData.php
Source

981          return $val;
982       } else {
983          return $this->obj->XML_val($fieldName, $args, $cache);
984       }
985    }
986    
987    function obj($fieldName, $args = null, $forceReturnObject = false) {
988       if(isset($this->extraData[$fieldName])) {
989          if(!is_object($this->extraData[$fieldName])) {
990             user_error("ViewableData_Customised::obj() '$fieldName' was requested from the array data as an object but it's not an object. I can't cast it.", E_USER_WARNING);
991          }
992          return $this->extraData[$fieldName];
993       } else {
994          return $this->obj->obj($fieldName, $args, $forceReturnObject);
995       }
996    }

Trace

* ViewableData_Customised::obj() 'DetailForm' was requested from the array data as an object but it's not an object. I can't cast it.
Line 990 of ViewableData.php
* ViewableData_Customised->obj(DetailForm,,1)
Line 35 of .cache.var.www.clients.client1.web1.web.SilverStripe.dataobject_manager.templates.DataObjectManager_popup.ss
* include(/var/www/clients/client1/web1/web/SilverStripe/silverstripe-cache/.cache.var.www.clients.client1.web1.web.SilverStripe.dataobject_manager.templates.DataObjectManager_popup.ss)
Line 354 of SSViewer.php
* SSViewer->process(ViewableData_Customised)
Line 773 of ViewableData.php
* ViewableData->renderWith(DataObjectManager_popup)
Line 535 of FileDataObjectManager.php
* FileDataObjectManager->saveImportForm(Array,Form,HTTPRequest)
Line 241 of Form.php
* Form->httpSubmission(HTTPRequest)
Line 129 of RequestHandler.php
* RequestHandler->handleRequest(HTTPRequest)
Line 143 of RequestHandler.php
* RequestHandler->handleRequest(HTTPRequest)
Line 143 of RequestHandler.php
* RequestHandler->handleRequest(HTTPRequest)
Line 143 of RequestHandler.php
* RequestHandler->handleRequest(HTTPRequest)
Line 122 of Controller.php
* Controller->handleRequest(HTTPRequest)
Line 277 of Director.php
* Director::handleRequest(HTTPRequest,Session)
Line 121 of Director.php
* Director::direct(/admin/assets/EditForm/field/Files/ImportForm)
Line 118 of main.php