title: ng2-charts update labels and data
body: <p>I'm trying to create dynamically a chart using ng2-chart,
  I get information from an angular 2 service, when I change only labels of chart it works and when I change data only it works, but When I change both just data are updated in the chart. have any one an explication  for this strange behavior.</p>
  
  <p>my template :</p>
  
  <pre class="lang-html prettyprint-override"><code>&lt;canvas baseChart height="130" width="180"  
      [data]="doughnutChartData"
      [labels]="doughnutChartLabels"
      [chartType]="doughnutChartType"
      (chartHover)="chartHovered($event)"
      (chartClick)="chartClicked($event)"&gt;
  &lt;/canvas&gt;
  </code></pre>
  
  <p>my class : </p>
  
  <pre><code>export class PlDoughnutComponent implements OnInit {
  
    constructor(private homeService: TileServiceService) { }
  
    ngOnInit() {
      this.updatePLdoughnut();
  
    }
  
    public util : UtilService = new UtilService();
    public doughnutChartLabels:string[] = ['Download Sales'];
    public doughnutChartData:number[] = [0,0,100];
    public doughnutChartType:string = 'doughnut';
  
    public updatePLdoughnut(){
  
      this.homeService.getTile().
      then(res =&gt; {
  
        this.doughnutChartLabels =  res.PLtypes;
        this.doughnutChartData = this.util.objectToIntArray(res.PLByTypes);
  
      })
    }
  }
  </code></pre>