reordering-instances.md

Reordering instances

It's sometimes useful to allow the user to rearrange instances right from the Entity List. Let's say we want to let the user choose some pages order:

Write the class

First, we need to write a class for the reordering itself, which must implement Code16\Sharp\EntityList\Commands\ReorderHandler, and therefore the reorder(array $ids) function.

Here's an example with Eloquent and a numerical order column:

    class PageReorderHandler implements ReorderHandler
    {
    
        function reorder(array $ids)
        {
            $pages = Page::whereIn("id", $ids)->get();
    
            foreach($pages as $page) {
                $page->order = array_search($page->id, $ids) + 1;
                $page->save();
            }
        }
    }

Configure reorder for the front-end

Then, in the SharpEntityList class, we have to configure our reorder handler:

    function buildListConfig()
    {
        $this->setReorderable(new PageReorderHandler());
    }

And that's it! The list now presents a "Reorder" button, and your code will be called when needed.

Handle exceptions

If you need to abort the process, for any reason, you can raise a Code16\Sharp\Exceptions\SharpException\SharpApplicativeException in the reorder(array $ids) function.