Run Chartjs Dart example

I'm trying to run the chartjs example of the dart port but It seems not to work. See screenshot with error message.

Any Idea where is the problem? Thanks

the source code for the example can be downloaded Chartjs Dart port Example

lib/chart.dart source:

library chart;

import 'dart:html';
import 'dart:math' as math;
import 'package:intl/intl.dart';

part 'src/base.dart';
part 'src/line.dart';
part 'src/bar.dart';
part 'src/bool.dart';
part 'src/animation.dart';

example/web/chart.html

<!DOCTYPE html>

<html>
  <head>
    <meta charset="utf-8">
    <title>Chart</title>
    <link rel="stylesheet" href="chart.css">
    <script type="application/dart" src="chart.dart"></script>
    <script src="packages/browser/dart.js"></script>
  </head>
  <body>
  </body>
</html>

example/web/chart.dart

library chart;

import 'dart:html';
import 'package:chart/chart.dart';


void main() {


  Line chart = new Line({
    'labels' : ["January","February","March","April","May","June","July","August"],
    'datasets' : [
                {
                  'fillColor' : "rgba(220,20,20,0.5)",
                  'strokeColor' : "rgba(0,0,0,1)",
                  'pointColor' : "rgba(220,220,220,1)",
                  'pointStrokeColor' : "#f00",
                  'data' : [1,4,5,2,5,6,3,7]
                },
                {
                  'fillColor' : "rgba(151,187,205,0.5)",
                  'strokeColor' : "rgba(151,187,205,1)",
                  'pointColor' : "rgba(151,187,205,1)",
                  'pointStrokeColor' : "#fff",
                  'data' : [3,-1,0,4,4,-2,4,1]
                },
                {
                  'fillColor' : "clear",
                  'strokeColor' : "rgba(151,187,205,1)",
                  'pointColor' : "rgba(151,187,205,1)",
                  'pointStrokeColor' : "#fff",
                  'data' : [-3,-3,-1,-4,-4,-3,-4,-1]
                }
    ]
  }, {
    'scaleOverride' : true, 
    'scaleMinValue' : 0.0, 
    'scaleMaxValue' : 35.0, 
    'scaleStepValue' : null, 
    'bezierCurve' : true, 
    'animation' : false,
    'titleText' : 'testest'     
    });


  Line chart2 = new Line({
      'labels' : ["1","2","3","4","5","6","7","8","9"],
      'datasets' : [
                  {
                    'fillColor' : "rgba(123,244,220,0.5)",
                    'strokeColor' : "rgba(220,220,220,1)",
                    'pointColor' : "rgba(220,220,220,1)",
                    'pointStrokeColor' : "#fff",
                    'data' : [1,1,0,0,1,1,1,0]
                  }
      ]

    }, {
      'animationEasing': 'easeOutElastic',
      'animation' : true,
      'bezierCurve' : true, 
      }
    );

  Bool chartBool = new Bool({
      'labels' : ["Montag","Dienstag","Mittwoch","Donnerstag","Freitag","Samstag","Sonntag"],
      'datasets' : [
                  {
                    'strokeColor' : "rgba(255,10,10,1)",
                    'data' : [{'x':0, 'y':0},{'x':2, 'y':0},{'x':3, 'y':1},{'x':20, 'y':0},{'x':30, 'y':0},{'x':40, 'y':0},{'x':45, 'y':0},{'x':63, 'y':0},{'x':100, 'y':0},{'x':123, 'y':1},{'x':128, 'y':0},{'x':130, 'y':0}]
                  }
                  ]

    }, {
      'animationEasing': 'easeOutElastic',
      'animation' : true
      }
    );

  Bar bar = new Bar({
                      'labels' : ["January","February","March","April","May","June","July"],
                      'datasets' : [
                                  {
                                    'fillColor' : "rgba(220,220,220,0.5)",
                                    'strokeColor' : "rgba(220,220,220,1)",
                                    'data' : [65,59,90,81,56,55,40]
                                  },
                                  {
                                    'fillColor' : "rgba(255,255,255,1)",
                                    'strokeColor' : "rgba(0,0,255,0.5)",
                                    'data' : [28,48,40,19,null,27,100]
                                  }
                                  ]

  }, null);

  Bar bar2 = new Bar({
                      'labels' : ["January","February","March","April","May","June","July"],
                      'datasets' : [
                                  {
                                    'fillColor' : "rgba(220,220,220,0.5)",
                                    'strokeColor' : "rgba(220,220,220,1)",
                                    'data' : [55,59,90,59,56,55,60]
                                  }]

  }, 
  {
    'titleText' : 'testest'     
  });

  DivElement containerBool = new DivElement();
  containerBool.style.height ='400px';
  containerBool.style.width =  '100%';
  document.body.children.add(containerBool);
  chartBool.show(containerBool);

  DivElement container = new DivElement();
  container.style.height ='400px';
  container.style.width =  '100%';
  document.body.children.add(container);
  chart.show(container);

  DivElement container2 = new DivElement();
  container2.style.height ='400px';
  container2.style.width =  '100%';
  document.body.children.add(container2);
  chart2.show(container2);

  DivElement container3 = new DivElement();
  container3.style.height ='400px';
  container3.style.width =  '100%';
  document.body.children.add(container3);
  bar.show(container3);

  DivElement container4 = new DivElement();
  container4.style.height ='400px';
  container4.style.width =  '100%';
  document.body.children.add(container4);
  bar2.show(container4);


}

Chartjs Dart error

Solution

This is obviously a bug in the example. Maybe the library was changed and the example not yet tested with the new version.

If you add two values to the map it works though

 Bool chartBool = new Bool({
      'labels' : ["Montag","Dienstag","Mittwoch","Donnerstag","Freitag","Samstag","Sonntag"],
      'datasets' : [
                  {
                    'name': 'bla',
                    'date': 'somedate',
                    'strokeColor' : "rgba(255,10,10,1)",

I just added the two lines name': 'bla','date': 'somedate'. It looks these values are just used as tooltip and the content doesn't really matter to overcome the exception.