public function render()
 {
     if (!isset($this->datas['labels'])) {
         $this->datas['labels'] = array();
     }
     return parent::render();
 }
 function __construct()
 {
     parent::__construct();
     $this->chart->type = 'areaspline';
     $this->xAxis = new XAxis();
     $this->yAxis = new YAxis();
     $this->initPlotOptions();
 }
 function __construct()
 {
     parent::__construct();
     $this->chart->type = 'area';
     $this->xAxis = new XAxis();
     $this->yAxis = new YAxis();
     $this->initPlotOptions();
     // $this->chart->alignTicks = true;
     // $this->chart->endOnTick = false;
 }
 function __construct()
 {
     parent::__construct();
     $this->chart->type = 'pie';
     $this->initPlotOptions();
 }