From 82aeceff70a15680c7bae6afb2358a86236d6eef Mon Sep 17 00:00:00 2001
From: "vn.py" <xiaoyou.chen@foxmail.com>
Date: Thu, 30 May 2019 12:34:07 +0800
Subject: [PATCH] [Mod] only register event if event_type is specified

---
 vnpy/trader/ui/widget.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/vnpy/trader/ui/widget.py b/vnpy/trader/ui/widget.py
index 899aefb9..f59e4c45 100644
--- a/vnpy/trader/ui/widget.py
+++ b/vnpy/trader/ui/widget.py
@@ -237,8 +237,9 @@ class BaseMonitor(QtWidgets.QTableWidget):
         """
         Register event handler into event engine.
         """
-        self.signal.connect(self.process_event)
-        self.event_engine.register(self.event_type, self.signal.emit)
+        if self.event_type:
+            self.signal.connect(self.process_event)
+            self.event_engine.register(self.event_type, self.signal.emit)
 
     def process_event(self, event):
         """