octobercms/october · error · SystemException

Invalid treeview branch group by mode: {}

Error message

Invalid treeview branch group by mode: {}

What it means

Error "Invalid treeview branch group by mode: {}" thrown in octobercms/october.

Source

Thrown at modules/backend/vuecomponents/treeview/NodeDefinition.php:353

            throw new SystemException('Treeview branch grouping is only supported for the LIST display mode');
        }

        if ($this->dragAndDropMode) {
            throw new SystemException('Drag and drop is not supported for treeview branches with enabled Group By feature');
        }

        $this->groupBy = $property;

        return $this;
    }

    /**
     * setGroupByMode
     */
    public function setGroupByMode(string $mode)
    {
        if (!in_array($mode, [self::GROUP_BY_MODE_NESTING, self::GROUP_BY_MODE_FOLDERS])) {
            throw new SystemException('Invalid treeview branch group by mode: '.$mode);
        }

        $this->groupByMode = $mode;

        return $this;
    }

    /**
     * addRootMenuItem
     */
    public function addRootMenuItem($type, ?string $label = null, ?string $command = null)
    {
        if (!$this->rootMenuItems) {
            $this->rootMenuItems = new ItemDefinition(ItemDefinition::TYPE_TEXT, 'root', 'none');
        }

        return $this->rootMenuItems->addItem($type, $label, $command);
    }

View on GitHub (pinned to b608633a7e)

When it happens

Trigger: Thrown at modules/backend/vuecomponents/treeview/NodeDefinition.php:353 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of octobercms/october@b608633a7e (2026-08-21). Data as JSON: /api/errors/408d4bc0916db317. Report an issue: GitHub.