octobercms/october · error · SystemException

Invalid treeview branch drag and drop mode: {}

Error message

Invalid treeview branch drag and drop mode: {}

What it means

Error "Invalid treeview branch drag and drop mode: {}" thrown in octobercms/october.

Source

Thrown at modules/backend/vuecomponents/treeview/NodeDefinition.php:309

     * child nodes using userData object properties.
     * Syntax: propertyName1,propertyName2:desc.
     */
    public function setSortBy(string $sortBy)
    {
        $this->sortBy = $sortBy;

        return $this;
    }

    /**
     * Sets tree branch drag and drop mode - sort, move (or both), or custom.
     * Only the root node drag and drop mode is considered.
     */
    public function setDragAndDropMode(array $mode)
    {
        foreach ($mode as $option) {
            if (!in_array($option, [self::DND_MOVE, self::DND_SORT, self::DND_CUSTOM, self::DND_CUSTOM_EXTERNAL])) {
                throw new SystemException('Invalid treeview branch drag and drop mode: '.$option);
            }

            if ($option === self::DND_CUSTOM && count($mode) > 1) {
                throw new SystemException('Treeview branch drag and drop Custom mode cannot be combined with other modes');
            }
        }

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

        $this->dragAndDropMode = $mode;

        return $this;
    }

    /**
     * Sets optional grouping for a tree branch.

View on GitHub (pinned to b608633a7e)

When it happens

Trigger: Thrown at modules/backend/vuecomponents/treeview/NodeDefinition.php:309 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/9bbecc042bbde489. Report an issue: GitHub.