Fix HTML set in _createChart

Author: Jelte Lagendijk

src/ChartJS/widgets/DoughnutChart/widget/DoughnutChart.js

@@ -138,8 +138,10 @@ define([
                 this._resize();
             }));
 
+            var content = this._data.object.get(this.numberInside);
+
             // Set the con
-            html.set(this._numberNode, this._data.object.get(this.numberInside).toString());
+            html.set(this._numberNode, content !== null ? content.toString() : "");
 
             // Add class to determain chart type
             this._addChartClass("chartjs-doughnut-chart");

src/ChartJS/widgets/PieChart/widget/PieChart.js

@@ -139,8 +139,10 @@ define([
                 };
                 this._chart = new this._chartJS(this._ctx, chartProperties);
 
+                var content = this._data.object.get(this.numberInside);
+
                 // Set the con
-                html.set(this._numberNode, this._data.object.get(this.numberInside).toString());
+                html.set(this._numberNode, content !== null ? content.toString() : "");
 
                 // Add class to determain chart type
                 this._addChartClass("chartjs-pie-chart");