Update charted to 0.4.8 and roll

packages/charted/lib/charts/cartesian_renderers/line_chart_renderer.dart

-//
 // Copyright 2014 Google Inc. All rights reserved.
 //
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file or at
 // https://developers.google.com/open-source/licenses/bsd
 //
 
 part of charted.charts;
 
 class LineChartRenderer extends CartesianRendererBase {
   final Iterable<int> dimensionsUsingBand = const [];
 
   final bool alwaysAnimate;
+  final bool showHoverCardOnTrackedDataPoints;
   final bool trackDataPoints;
   final bool trackOnDimensionAxis;
   final int quantitativeScaleProximity;
 
   bool _trackingPointsCreated = false;
   List _xPositions = [];
 
   // Currently hovered row/column
   int _savedOverRow = 0;
   int _savedOverColumn = 0;
 
   int currentDataIndex = -1;
 
   @override
   final String name = "line-rdr";
 
   LineChartRenderer(
       {this.alwaysAnimate: false,
+      this.showHoverCardOnTrackedDataPoints: false,
       this.trackDataPoints: true,
       this.trackOnDimensionAxis: false,
       this.quantitativeScaleProximity: 5});
 
   // Returns false if the number of dimension axes on the area is 0.
   // Otherwise, the first dimension scale is used to render the chart.
   @override
   bool prepare(ChartArea area, ChartSeries series) {
     _ensureAreaAndSeries(area, series);
     if (trackDataPoints != false) {
@@ skipping 64 matching lines @@
         ..on('click', (d, i, e) => _mouseClickHandler(d, i, e))
         ..on('mouseover', (d, i, e) => _mouseOverHandler(d, i, e))
         ..on('mouseout', (d, i, e) => _mouseOutHandler(d, i, e));
     }
 
     svgLines.exit.remove();
   }
 
   @override
   void dispose() {
+    _disposer.dispose();
     if (root == null) return;
     root.selectAll('.line-rdr-line').remove();
     root.selectAll('.line-rdr-point').remove();
-    _disposer.dispose();
   }
 
   @override
   void handleStateChanges(List<ChangeRecord> changes) {
     var lines = host.querySelectorAll('.line-rdr-line');
     if (lines == null || lines.isEmpty) return;
 
     for (int i = 0, len = lines.length; i < len; ++i) {
       var line = lines.elementAt(i),
           column = int.parse(line.dataset['column']),
@@ skipping 28 matching lines @@
       })
       ..on('click', _mouseClickHandler)
       ..on('mousemove', _mouseOverHandler) // Ensure that we update values
       ..on('mouseover', _mouseOverHandler)
       ..on('mouseout', _mouseOutHandler);
 
     linePoints.exit.remove();
     _trackingPointsCreated = true;
   }
 
-  void _showTrackingCircles(int row) {
+  void _showTrackingCircles(ChartEvent event, int row) {
     if (_trackingPointsCreated == false) {
       _createTrackingCircles();
     }
 
     var yScale = area.measureScales(series).first;
     root.selectAll('.line-rdr-point').each((d, i, e) {
       var x = _xPositions[row],
           measureVal = area.data.rows.elementAt(row).elementAt(d);
       if (measureVal != null && measureVal.isFinite) {
         var color = colorForColumn(d), filter = filterForColumn(d);
@@ skipping 10 matching lines @@
           e.attributes.remove('filter');
         } else {
           e.attributes['filter'] = filter;
         }
       } else {
         e.style
           ..setProperty('opacity', '$EPSILON')
           ..setProperty('visibility', 'hidden');
       }
     });
+
+    if (showHoverCardOnTrackedDataPoints) {
+      var firstMeasureColumn = series.measures.first;
+      mouseOverController.add(new DefaultChartEventImpl(
+          event.source, area, series, row, firstMeasureColumn, 0));
+      _savedOverRow = row;
+      _savedOverColumn = firstMeasureColumn;
+    }
   }
 
-  void _hideTrackingCircles() {
+  void _hideTrackingCircles(ChartEvent event) {
     root.selectAll('.line-rdr-point')
       ..style('opacity', '0.0')
       ..style('visibility', 'hidden');
+    if (showHoverCardOnTrackedDataPoints) {
+      mouseOutController.add(new DefaultChartEventImpl(
+          event.source, area, series, _savedOverRow, _savedOverColumn, 0));
+    }
   }
 
   int _getNearestRowIndex(num x) {
-    var lastSmallerValue = 0;
+    double lastSmallerValue = 0.0;
     var chartX = x - area.layout.renderArea.x;
     for (var i = 0; i < _xPositions.length; i++) {
-      var pos = _xPositions[i];
+      double pos = _xPositions[i].toDouble();
       if (pos < chartX) {
         lastSmallerValue = pos;
       } else {
         return i == 0
             ? 0
             : (chartX - lastSmallerValue <= pos - chartX) ? i - 1 : i;
       }
     }
     return _xPositions.length - 1;
   }
 
   void _trackPointerInArea() {
     _trackingPointsCreated = false;
     _disposer.add(area.onMouseMove.listen((ChartEvent event) {
       if (area.layout.renderArea.contains(event.chartX, event.chartY)) {
         var row = _getNearestRowIndex(event.chartX);
-        window.animationFrame.then((_) => _showTrackingCircles(row));
+        window.animationFrame.then((_) {
+          _showTrackingCircles(event, row);
+        });
       } else {
-        _hideTrackingCircles();
+        _hideTrackingCircles(event);
       }
     }));
     _disposer.add(area.onMouseOut.listen((ChartEvent event) {
-      _hideTrackingCircles();
+      _hideTrackingCircles(event);
     }));
   }
 
   void _mouseClickHandler(d, int i, Element e) {
     if (area.state != null) {
-      area.state.select(int.parse(e.dataset['column']));
+      var selectedColumn = int.parse(e.dataset['column']);
+      area.state.isSelected(selectedColumn)
+          ? area.state.unselect(selectedColumn)
+          : area.state.select(selectedColumn);
     }
     if (mouseClickController != null && e.tagName == 'circle') {
       var row = int.parse(e.dataset['row']),
           column = int.parse(e.dataset['column']);
       mouseClickController.add(
           new DefaultChartEventImpl(scope.event, area, series, row, column, d));
     }
   }
 
   void _mouseOverHandler(d, int i, Element e) {
@@ skipping 12 matching lines @@
     if (area.state != null &&
         area.state.preview == int.parse(e.dataset['column'])) {
       area.state.preview = null;
     }
     if (mouseOutController != null && e.tagName == 'circle') {
       mouseOutController.add(new DefaultChartEventImpl(
           scope.event, area, series, _savedOverRow, _savedOverColumn, d));
     }
   }
 }