display column expansion in dcat admin

Question

In UserController $grid->post->display('users_id')->expand(User::make(['users_id'])); $grid->post->expand(function () { return User::make(['id','content', 'created_at' => $this->title]); });

In User Model ` public function render() {

    $id = $this->key;
    $type = $this->post_type;
    $data = User::where('id', $id)->where('users_id', $type)->get(['id', 'content', 'created_at'])->toArray();
    $titles = [
        'Id',
        'Content',
        'Created At',
    ];

    return Table::make($titles, $data);
}`

please help on how to ulter this coding to create a table which column expansion in dcat-admin laravel