Allow drag and drop from rqt_topic_monitor

resource/speedometer.ui

@@ -22,6 +22,12 @@
     <height>500</height>
    </size>
   </property>
+  <property name="contextMenuPolicy">
+   <enum>Qt::DefaultContextMenu</enum>
+  </property>
+  <property name="acceptDrops">
+   <bool>true</bool>
+  </property>
   <property name="windowTitle">
    <string>Speedometer</string>
   </property>
@@ -153,6 +159,9 @@ p, li { white-space: pre-wrap; }
      <height>411</height>
     </rect>
    </property>
+   <property name="acceptDrops">
+    <bool>true</bool>
+   </property>
   </widget>
   <widget class="QLabel" name="units_label">
    <property name="geometry">
@@ -211,6 +220,9 @@ p, li { white-space: pre-wrap; }
      <height>31</height>
     </rect>
    </property>
+   <property name="dragEnabled">
+    <bool>false</bool>
+   </property>
   </widget>
  </widget>
  <customwidgets>

resource/steering_wheel.ui

@@ -22,6 +22,9 @@
     <height>550</height>
    </size>
   </property>
+  <property name="acceptDrops">
+   <bool>true</bool>
+  </property>
   <property name="windowTitle">
    <string>SteeringWheel</string>
   </property>

resource/throttle_brake_pedals.ui

@@ -22,6 +22,9 @@
     <height>550</height>
    </size>
   </property>
+  <property name="acceptDrops">
+   <bool>true</bool>
+  </property>
   <property name="windowTitle">
    <string>ThrottleBrakePedals</string>
   </property>

src/rqt_gauges/speedometer_widget.py

@@ -43,6 +43,19 @@ def __init__(self, node):
         self.subscribe_button.pressed.connect(self.updateSubscription)
         self.speedometer_gauge.updateValueSignal.connect(self.updateValue)
 
+    def dragEnterEvent(self, event):
+        event.accept()
+
+    def dropEvent(self, event):
+        if event.mimeData().hasText():
+            topic_name = str(event.mimeData().text())
+        else:
+            droped_item = event.source().selectedItems()[0]
+            topic_name = str(droped_item.data(0, Qt.UserRole))
+        self.topic_to_subscribe.setText(topic_name)
+        self.updateSubscription()
+        event.accept()
+
     @pyqtSlot()
     def updateMinValue(self):
         new_min_value = self.min_value.toPlainText()

src/rqt_gauges/steering_wheel_widget.py

@@ -39,6 +39,19 @@ def __init__(self, node):
         self.subscribe_button.pressed.connect(self.updateSubscription)
         self.steering_wheel_gauge.updateValueSignal.connect(self.updateValue)
 
+    def dragEnterEvent(self, event):
+        event.accept()
+
+    def dropEvent(self, event):
+        if event.mimeData().hasText():
+            topic_name = str(event.mimeData().text())
+        else:
+            droped_item = event.source().selectedItems()[0]
+            topic_name = str(droped_item.data(0, Qt.UserRole))
+        self.topic_to_subscribe.setText(topic_name)
+        self.updateSubscription()
+        event.accept()
+
     @pyqtSlot()
     def updateMaxValue(self):
         new_max_value = self.max_value.toPlainText()

src/rqt_gauges/throttle_brake_pedals_widget.py

@@ -1,7 +1,7 @@
 import os
 
 from ament_index_python.resources import get_resource
-from PyQt5.QtCore import pyqtSignal, pyqtSlot
+from PyQt5.QtCore import pyqtSignal, pyqtSlot, Qt
 from PyQt5.QtWidgets import QWidget
 from python_qt_binding import loadUi
 from rosidl_runtime_py.utilities import get_message
@@ -46,6 +46,24 @@ def __init__(self, node):
         self.updateThrottleValueSignal.connect(self.updateThrottle)
         self.updateBrakeValueSignal.connect(self.updateBrake)
 
+    def dragEnterEvent(self, event):
+        event.accept()
+
+    def dropEvent(self, event):
+        if event.mimeData().hasText():
+            topic_name = str(event.mimeData().text())
+        else:
+            droped_item = event.source().selectedItems()[0]
+            topic_name = str(droped_item.data(0, Qt.UserRole))
+
+        if (event.pos().x() < self.size().width() / 2):
+            self.throttle_topic_to_subscribe.setText(topic_name)
+            self.throttleUpdateSubscription()
+        else:
+            self.brake_topic_to_subscribe.setText(topic_name)
+            self.brakeUpdateSubscription()
+        event.accept()
+
     @pyqtSlot()
     def throttleUpdateSubscription(self):
         if self.node.destroy_subscription(self.throttle_sub):