lineChar问题求助啊~~~~

我在window中加载了一个linechart，extend: 'Ext.chart.Chart',
height:200,
id:'TMChart',
width:650,
store:["Flb_web.store.TakeMedicine"],
alias:'widget.takeMedicineChart',
axes: [{
type: 'Numeric',
position: 'left',
fields: ['num'],
grid: true,
minimum: 0
}, {
type: 'Time',
position: 'bottom',
fields: ['takeMedicineDate'],
groupBy: 'Ext.DATE.DAY',
dateFormat: 'd',
grid: true
}],
series: [{
type: 'line',
highlight: {
size: 7,
radius: 7
},
axis: 'left',
xField: 'takeMedicineDate',
yField: 'num',
markerConfig: {
type: 'cross',
size: 4,
radius: 4,
'stroke-width': 0
}
}]