Polar area legend toggles data

diff --git a/src/controllers/controller.polarArea.js b/src/controllers/controller.polarArea.js
index d9f15b59a5af6372592328ecdf5683f32ab07c44..8b5ceef41fa82b8442d0c536df5eef6c22eb0474 100644 (file)
--- a/src/controllers/controller.polarArea.js
+++ b/src/controllers/controller.polarArea.js
@@ -43,6 +43,7 @@
                                                return {
                                                        text: label,
                                                        fillStyle: data.datasets[0].backgroundColor[i],
+                                                       hidden: isNaN(data.datasets[0].data[i]),
 
                                                        // Extra data used for toggling the correct item
                                                        index: i
@@ -50,7 +51,21 @@
                                        });
                                }
                        },
-                       onClick: null,
+                       onClick: function(e, legendItem) {
+                               helpers.each(this.chart.data.datasets, function(dataset) {
+                                       dataset.metaHiddenData = dataset.metaHiddenData || [];
+                                       var idx = legendItem.index;
+
+                                       if (!isNaN(dataset.data[idx])) {
+                                               dataset.metaHiddenData[idx] = dataset.data[idx];
+                                               dataset.data[idx] = NaN;
+                                       } else if (!isNaN(dataset.metaHiddenData[idx])) {
+                                               dataset.data[idx] = dataset.metaHiddenData[idx];
+                                       }
+                               });
+
+                               this.chart.update();
+                       }
                },
 
                // Need to override these to give a nice default
@@ -163,13 +178,23 @@
                                this.updateElement(arc, index, reset);
                        }, this);
                },
+
                updateElement: function(arc, index, reset) {
-                       var circumference = 1 / this.getDataset().data.length * 2;
+                       var circumference = this.calculateCircumference(this.getDataset().data[index]);
                        var centerX = (this.chart.chartArea.left + this.chart.chartArea.right) / 2;
                        var centerY = (this.chart.chartArea.top + this.chart.chartArea.bottom) / 2;
 
-                       var startAngle = (-0.5 * Math.PI) + (Math.PI * circumference) * index;
-                       var endAngle = startAngle + (circumference * Math.PI);
+                       // If there is NaN data before us, we need to calculate the starting angle correctly. 
+                       // We could be way more efficient here, but its unlikely that the polar area chart will have a lot of data
+                       var notNullIndex = 0;
+                       for (var i = 0; i < index; ++i) {
+                               if (!isNaN(this.getDataset().data[i])) {
+                                       ++notNullIndex;
+                               }
+                       }
+
+                       var startAngle = (-0.5 * Math.PI) + (circumference * notNullIndex);
+                       var endAngle = startAngle + circumference;
 
                        var resetModel = {
                                x: centerX,
@@ -241,10 +266,15 @@
                },
 
                calculateCircumference: function(value) {
-                       if (this.getDataset().total > 0) {
-                               return (Math.PI * 2) * (value / this.getDataset().total);
-                       } else {
+                       if (isNaN(value)) {
                                return 0;
+                       } else {
+                               // Count the number of NaN values 
+                               var numNaN = helpers.where(this.getDataset().data, function(data) {
+                                       return isNaN(data);
+                               }).length;
+
+                               return (2 * Math.PI) / (this.getDataset().data.length - numNaN);
                        }
                },
                updateScaleRange: function() {