diff --git a/artiq/gui/applets.py b/artiq/gui/applets.py
index ddc801726..2a8732f5a 100644
--- a/artiq/gui/applets.py
+++ b/artiq/gui/applets.py
@@ -8,6 +8,7 @@ from quamash import QtCore, QtGui, QtWidgets
 
 from artiq.protocols.pipe_ipc import AsyncioParentComm
 from artiq.protocols import pyon
+from artiq.gui.tools import QDockWidgetCloseDetect
 
 
 logger = logging.getLogger(__name__)
@@ -84,11 +85,9 @@ class AppletIPCServer(AsyncioParentComm):
         await asyncio.wait([self.server_task])
 
 
-class AppletDock(QtWidgets.QDockWidget):
-    sigClosed = QtCore.pyqtSignal()
-
+class AppletDock(QDockWidgetCloseDetect):
     def __init__(self, datasets_sub, uid, name, command):
-        QtWidgets.QDockWidget.__init__(self, "Applet: " + name)
+        QDockWidgetCloseDetect.__init__(self, "Applet: " + name)
         self.setObjectName("applet" + str(uid))
 
         self.datasets_sub = datasets_sub
@@ -164,10 +163,6 @@ class AppletDock(QtWidgets.QDockWidget):
         await self.terminate()
         await self.start()
 
-    def closeEvent(self, event):
-        QtWidgets.QDockWidget.closeEvent(self, event)
-        self.sigClosed.emit()
-
 
 _templates = [
     ("Big number", "{python} -m artiq.applets.big_number "
diff --git a/artiq/gui/experiments.py b/artiq/gui/experiments.py
index 8b81edc92..5536c30d3 100644
--- a/artiq/gui/experiments.py
+++ b/artiq/gui/experiments.py
@@ -7,7 +7,7 @@ from quamash import QtGui, QtCore, QtWidgets
 
 from pyqtgraph import LayoutWidget
 
-from artiq.gui.tools import log_level_to_name
+from artiq.gui.tools import log_level_to_name, QDockWidgetCloseDetect
 from artiq.gui.entries import argty_to_entry
 
 
@@ -133,12 +133,10 @@ class _ArgumentEditor(QtGui.QTreeWidget):
                 pass
 
 
-class _ExperimentDock(QtWidgets.QDockWidget):
-    sigClosed = QtCore.pyqtSignal()
-
+class _ExperimentDock(QDockWidgetCloseDetect):
     def __init__(self, manager, expurl):
         name = "Exp: " + expurl
-        QtWidgets.QDockWidget.__init__(self, name)
+        QDockWidgetCloseDetect.__init__(self, name)
         self.setObjectName(name)
 
         self.layout = QtWidgets.QGridLayout()
@@ -297,10 +295,6 @@ class _ExperimentDock(QtWidgets.QDockWidget):
         self.argeditor = _ArgumentEditor(self.manager, self, self.expurl)
         self.layout.addWidget(self.argeditor, 0, 0, 1, 5)
 
-    def closeEvent(self, event):
-        QtWidgets.QDockWidget.closeEvent(self, event)
-        self.sigClosed.emit()
-
     def save_state(self):
         return self.argeditor.save_state()
 
diff --git a/artiq/gui/log.py b/artiq/gui/log.py
index d853e0f1b..005fe626d 100644
--- a/artiq/gui/log.py
+++ b/artiq/gui/log.py
@@ -7,7 +7,7 @@ from functools import partial
 from quamash import QtGui, QtCore, QtWidgets
 from pyqtgraph import LayoutWidget
 
-from artiq.gui.tools import log_level_to_name
+from artiq.gui.tools import log_level_to_name, QDockWidgetCloseDetect
 
 
 def _make_wrappable(row, width=30):
@@ -140,11 +140,9 @@ class _LogFilterProxyModel(QtCore.QSortFilterProxyModel):
         self.invalidateFilter()
 
 
-class _LogDock(QtWidgets.QDockWidget):
-    sigClosed = QtCore.pyqtSignal()
-
+class _LogDock(QDockWidgetCloseDetect):
     def __init__(self, manager, name, log_sub):
-        QtWidgets.QDockWidget.__init__(self, "Log")
+        QDockWidgetCloseDetect.__init__(self, "Log")
         self.setObjectName(name)
 
         grid = LayoutWidget()
@@ -254,10 +252,6 @@ class _LogDock(QtWidgets.QDockWidget):
         self.table_model_filter.rowsInserted.connect(self.rows_inserted_after)
         self.table_model_filter.rowsRemoved.connect(self.rows_removed)
 
-    def closeEvent(self, event):
-        QtWidgets.QDockWidget.closeEvent(self, event)
-        self.sigClosed.emit()
-
     def save_state(self):
         return {
             "min_level_idx": self.filter_level.currentIndex(),
diff --git a/artiq/gui/tools.py b/artiq/gui/tools.py
index 5fa701d81..5de02c3a9 100644
--- a/artiq/gui/tools.py
+++ b/artiq/gui/tools.py
@@ -1,6 +1,6 @@
 import logging
 
-from quamash import QtCore
+from PyQt5 import QtCore, QtWidgets, QtGui
 
 
 def log_level_to_name(level):
@@ -27,3 +27,12 @@ class _WheelFilter(QtCore.QObject):
 def disable_scroll_wheel(widget):
     widget.setFocusPolicy(QtCore.Qt.StrongFocus)
     widget.installEventFilter(_WheelFilter(widget))
+
+
+class QDockWidgetCloseDetect(QtWidgets.QDockWidget):
+    sigClosed = QtCore.pyqtSignal()
+
+    def event(self, event):
+        if isinstance(event, QtGui.QCloseEvent):
+            self.sigClosed.emit()
+        return QtWidgets.QDockWidget.event(self, event)