highcharts shows exception "c is undefined" for pie chart - highcharts

Question

I'm using highcharts in GXT application.
There are 2 charts in GXT collapsible panel,
one is column chart, the other one is pie chart
And there always pop up an exception showing
(TypeError): c is undefined
fileName: http://127.0.0.1:8888/js/highcharts.js
lineNumber: 118
columnNumber: 0
when injecting the json data for pie chart(column chart works normally).
Does any one can help me to check this?
Here is the JSON data for pie chart
{
"title" : {
"text" : "pie chart"
},
"chart" : {
"type" : "pie",
"renderTo" : "container",
"events" : {
"load" : function(event) { this.id = 'chart320002'; $wnd.registerChart(this, true);}
}
},
"series" : [ {
"name" : "COUNT",
"data" : [ [ "A", 37 ], [ "B", 23 ], [ "C", 21 ], [ "D", 21 ], [ "E", 23 ], [ "F", 19 ], [ "G", 20 ] ]
} ],
"exporting" : {
"buttons" : {"printButton":{"enabled":false}},
"type" : "img/png",
"url" : "http://127.0.0.1:8888/export/hiChart"
},
"credits" : {
"enabled" : false
},
"plotOptions" : {
"pie" : {"dataLabels":{"formatter":function(){return this.point.name+': '+$wnd.Highcharts.numberFormat(this.percentage,2)+'%';}}}
},
"xAxis" : {
"title" : {
"text" : "Compliant"
}
},
"yAxis" : {
"title" : { }
}
}

Answer 1

UPDATE: Include the code from the Highcharts web site, i.e. http://code.highcharts.com/highcharts.js. When I do this, I get pie charts!! Woot!
I have the same issue using different data. All of the line based charts plot correctly.
I copied your JSON to jsfiddle and it runs. Then I pasted your JSON into my project, same error, "c is undefined".
The only difference I can see is that when I do this:
$('#chart').highcharts({...});
I get $(...).highcharts is not a function, so I am using:
var chart = Highcharts.Chart({...});
Code for my pie chart that generates the same error.
var piechart = new Highcharts.Chart({
chart: {
borderColor: '#000000',
borderWidth: 2,
margin: 32,
renderTo: 'piechart',
type: chartType
},
series: [{
name: 'Channel',
data: [{
name: 'Web',
y: 75.6
},{
name: 'Mail',
y: 24.4
}]
}],
title: {
text: 'Revenue'
},
});
Which also runs in jsfiddler as $('#piechart').highcharts ..., but not my web page.