diff --git a/vnpy/app/cta_backtester/ui/widget.py b/vnpy/app/cta_backtester/ui/widget.py
index 5c5787af..ef54804f 100644
--- a/vnpy/app/cta_backtester/ui/widget.py
+++ b/vnpy/app/cta_backtester/ui/widget.py
@@ -1045,4 +1045,4 @@ class CandleChartDialog(QtWidgets.QDialog):
     
     def is_updated(self):
         """"""
-        return self.updated
\ No newline at end of file
+        return self.updated
diff --git a/vnpy/chart/widget.py b/vnpy/chart/widget.py
index caf4c8a9..17f957ce 100644
--- a/vnpy/chart/widget.py
+++ b/vnpy/chart/widget.py
@@ -27,8 +27,8 @@ class ChartWidget(pg.PlotWidget):
 
         self._manager: BarManager = BarManager()
 
-        self._plots: Dict[str, ChartItem] = {}
-        self._items: Dict[str, pg.GraphicsObject] = {}
+        self._plots: Dict[str, pg.GraphicsObject] = {}
+        self._items: Dict[str, ChartItem] = {}
         self._item_plot_map: Dict[ChartItem, pg.GraphicsObject] = {}
 
         self._first_plot: pg.PlotItem = None