tree = $tree; $this->tools = new Collection(); } /** * Prepend a tool. * * @param string $tool * * @return $this */ public function add($tool) { $this->tools->push($tool); return $this; } /** * Render header tools bar. * * @return string */ public function render() { return $this->tools->map([Helper::class, 'render'])->implode(' '); } }