Handle opacity in the tooltip update method

diff --git a/src/core/core.tooltip.js b/src/core/core.tooltip.js
index 055d68eb8e6e7d7fbe7b94dd09c504e3b88ad899..b8ec75b3a74680ce90f7c547ffc480e49fd723a4 100644 (file)
--- a/src/core/core.tooltip.js
+++ b/src/core/core.tooltip.js
@@ -197,63 +197,70 @@
 
                        var ctx = this._chart.ctx;
 
-                       var element = this._active[0],
-                               labelColors = [],
-                               tooltipPosition;
-
-                       var tooltipItems = [];
-
-                       if (this._options.tooltips.mode == 'single') {
-                               var yScale = element._yScale || element._scale; // handle radar || polarArea charts
-                               tooltipItems.push({
-                                       xLabel: element._xScale ? element._xScale.getLabelForIndex(element._index, element._datasetIndex) : '',
-                                       yLabel: yScale ? yScale.getLabelForIndex(element._index, element._datasetIndex) : '',
-                                       index: element._index,
-                                       datasetIndex: element._datasetIndex,
-                               });
-                               tooltipPosition = this._active[0].tooltipPosition();
-                       } else {
-                               helpers.each(this._data.datasets, function(dataset, datasetIndex) {
-                                       if (!helpers.isDatasetVisible(dataset)) {
-                                               return;
-                                       }
-                                       var currentElement = dataset.metaData[element._index];
-                                       var yScale = element._yScale || element._scale; // handle radar || polarArea charts
+                       if(this._active.length){
+                               this._model.opacity = 1;
+
+                               var element = this._active[0],
+                                       labelColors = [],
+                                       tooltipPosition;
+
+                               var tooltipItems = [];
 
+                               if (this._options.tooltips.mode == 'single') {
+                                       var yScale = element._yScale || element._scale; // handle radar || polarArea charts
                                        tooltipItems.push({
-                                               xLabel: currentElement._xScale ? currentElement._xScale.getLabelForIndex(currentElement._index, currentElement._datasetIndex) : '',
-                                               yLabel: yScale ? yScale.getLabelForIndex(currentElement._index, currentElement._datasetIndex) : '',
+                                               xLabel: element._xScale ? element._xScale.getLabelForIndex(element._index, element._datasetIndex) : '',
+                                               yLabel: yScale ? yScale.getLabelForIndex(element._index, element._datasetIndex) : '',
                                                index: element._index,
-                                               datasetIndex: datasetIndex,
+                                               datasetIndex: element._datasetIndex,
                                        });
-                               });
-
-                               helpers.each(this._active, function(active, i) {
-                                       labelColors.push({
-                                               borderColor: active._view.borderColor,
-                                               backgroundColor: active._view.backgroundColor
+                                       tooltipPosition = this._active[0].tooltipPosition();
+                               } else {
+                                       helpers.each(this._data.datasets, function(dataset, datasetIndex) {
+                                               if (!helpers.isDatasetVisible(dataset)) {
+                                                       return;
+                                               }
+                                               var currentElement = dataset.metaData[element._index];
+                                               var yScale = element._yScale || element._scale; // handle radar || polarArea charts
+
+                                               tooltipItems.push({
+                                                       xLabel: currentElement._xScale ? currentElement._xScale.getLabelForIndex(currentElement._index, currentElement._datasetIndex) : '',
+                                                       yLabel: yScale ? yScale.getLabelForIndex(currentElement._index, currentElement._datasetIndex) : '',
+                                                       index: element._index,
+                                                       datasetIndex: datasetIndex,
+                                               });
                                        });
-                               }, this);
 
-                               tooltipPosition = this._active[0].tooltipPosition();
-                               tooltipPosition.y = this._active[0]._yScale.getPixelForDecimal(0.5);
-                       }
+                                       helpers.each(this._active, function(active, i) {
+                                               labelColors.push({
+                                                       borderColor: active._view.borderColor,
+                                                       backgroundColor: active._view.backgroundColor
+                                               });
+                                       }, this);
 
-                       // Build the Text Lines
-                       helpers.extend(this._model, {
-                               title: this.getTitle(tooltipItems, this._data),
-                               beforeBody: this.getBeforeBody(tooltipItems, this._data),
-                               body: this.getBody(tooltipItems, this._data),
-                               afterBody: this.getAfterBody(tooltipItems, this._data),
-                               footer: this.getFooter(tooltipItems, this._data),
-                       });
+                                       tooltipPosition = this._active[0].tooltipPosition();
+                                       tooltipPosition.y = this._active[0]._yScale.getPixelForDecimal(0.5);
+                               }
 
-                       helpers.extend(this._model, {
-                               x: Math.round(tooltipPosition.x),
-                               y: Math.round(tooltipPosition.y),
-                               caretPadding: tooltipPosition.padding,
-                               labelColors: labelColors,
-                       });
+                               // Build the Text Lines
+                               helpers.extend(this._model, {
+                                       title: this.getTitle(tooltipItems, this._data),
+                                       beforeBody: this.getBeforeBody(tooltipItems, this._data),
+                                       body: this.getBody(tooltipItems, this._data),
+                                       afterBody: this.getAfterBody(tooltipItems, this._data),
+                                       footer: this.getFooter(tooltipItems, this._data),
+                               });
+
+                               helpers.extend(this._model, {
+                                       x: Math.round(tooltipPosition.x),
+                                       y: Math.round(tooltipPosition.y),
+                                       caretPadding: tooltipPosition.padding,
+                                       labelColors: labelColors,
+                               });
+                       }
+                       else{
+                               this._model.opacity = 0;
+                       }
 
                        if (this._options.tooltips.custom) {
                                this._options.tooltips.custom.call(this, this._model);