Traceback (most recent call last):
File "/Users/wanghaibo/opt/miniconda3/lib/python3.7/site-packages/vnpy/trader/ui/mainwindow.py", line 281, in open_widget
widget = widget_class(self.main_engine, self.event_engine)
File "/Users/wanghaibo/opt/miniconda3/lib/python3.7/site-packages/vnpy/app/cta_backtester/ui/widget.py", line 48, in init
self.init_ui()
File "/Users/wanghaibo/opt/miniconda3/lib/python3.7/site-packages/vnpy/app/cta_backtester/ui/widget.py", line 210, in init_ui
self.candle_dialog = CandleChartDialog()
File "/Users/wanghaibo/opt/miniconda3/lib/python3.7/site-packages/vnpy/app/cta_backtester/ui/widget.py", line 1142, in init
self.init_ui()
File "/Users/wanghaibo/opt/miniconda3/lib/python3.7/site-packages/vnpy/app/cta_backtester/ui/widget.py", line 1152, in init_ui
self.chart.add_plot("volume", maximum_height=200)
File "/Users/wanghaibo/opt/miniconda3/lib/python3.7/site-packages/vnpy/chart/widget.py", line 72, in add_plot
plot = pg.PlotItem(axisItems={'bottom': self._x_axis})
File "/Users/wanghaibo/opt/miniconda3/lib/python3.7/site-packages/pyqtgraph/graphicsItems/PlotItem/PlotItem.py", line 158, in init
self.setAxisItems(axisItems)
File "/Users/wanghaibo/opt/miniconda3/lib/python3.7/site-packages/pyqtgraph/graphicsItems/PlotItem/PlotItem.py", line 325, in setAxisItems
if axis != self.axes[k]["item"]:
KeyError: 'bottom'
