[Fix] typo

vnpy/app/spread_trading/base.py

@@ -136,7 +136,7 @@ class SpreadData:
         self.active_leg: LegData = None
         self.passive_legs: List[LegData] = []
 
-        self.min_volume = 0.1
+        self.min_volume = 0.001
 
         # For calculating spread price
         self.price_multipliers: Dict[str, int] = price_multipliers

vnpy/app/spread_trading/ui/widget.py

@@ -228,7 +228,7 @@ class SpreadAlgoWidget(QtWidgets.QFrame):
         )
 
         self.offset_combo = QtWidgets.QComboBox()
-        self.offset_combo.addItem(
+        self.offset_combo.addItems(
             [Offset.NONE.value, Offset.OPEN.value, Offset.CLOSE.value]
         )
 

vnpy/gateway/bitmex/bitmex_gateway.py

@@ -744,6 +744,10 @@ class BitmexWebsocketApi(WebsocketClient):
             gateway_name=self.gateway_name,
         )
 
+        # avgEntryPrice may be None instead of 0 sometimes
+        if position.price is None:
+            position.price = 0
+
         self.gateway.on_position(position)
 
     def on_account(self, d):