Angular 角度泳道ngx图表，悬停工具提示时nativeElement错误

我已经调试这两天了，没有类似的在线。我正在使用库，当我悬停在图表上时，我遇到了一个问题

图表按预期呈现，但一旦我在图表中悬停以显示工具提示，我的应用程序就会崩溃，并显示以下错误：

TypeError: Cannot read property 'nativeElement' of undefined
    at TooltipContentComponent.push../node_modules/@swimlane/ngx-charts/fesm5/swimlane-ngx-charts.js.TooltipContentComponent.positionCaret (swimlane-ngx-charts.js:493)
    at TooltipContentComponent.push../node_modules/@swimlane/ngx-charts/fesm5/swimlane-ngx-charts.js.TooltipContentComponent.position (swimlane-ngx-charts.js:482)
    at TooltipContentComponent.push../node_modules/@swimlane/ngx-charts/fesm5/swimlane-ngx-charts.js.TooltipContentComponent.onWindowResize (swimlane-ngx-charts.js:503)
    at TooltipContentComponent.onWindowResize (swimlane-ngx-charts.js:203)
    at Object.eval [as handleEvent] (TooltipContentComponent_Host.ngfactory.js? [sm]:1)
    at handleEvent (core.js:30907)
    at callWithDebugContext (core.js:31977)
    at Object.debugHandleEvent [as handleEvent] (core.js:31704)
    at dispatchEvent (core.js:21355)
    at core.js:30116 

这是我的密码

            <ngx-charts-line-chart
              [results]="model.lineChartData.chartPoints"
              [xAxis]="model.chartOptions.showXAxis"
              [yAxis]="model.chartOptions.showYAxis"
              [showXAxisLabel]="model.chartOptions.showXAxis"
              [showYAxisLabel]="model.chartOptions.showYAxis"
              [xAxisLabel]="model.lineChartData.xAxisLabel"
              [yAxisLabel]="model.lineChartData.yAxisLabel"
              [tooltipDisabled]="false"
              [legend]="model.chartOptions.showLegend"
              [autoScale]="model.chartOptions.autoScale">
            </ngx-charts-line-chart>

谢谢您的时间：）

export class ChartComponent {
  @Input() model: ChartModel;

  constructor(public logger: Logger,
              private router: Router) {
  }