ctrl_panel: Code cleanup

* Remove unnecessary duplication of `THERMOSTAT_PARAMETERS`

* i -> ch

* Separate ParameterTree and Parameter initiation

* Remove extra "channel" option to root parameters, as the "value"
option is already the channel number

pythermostat/pythermostat/gui/view/ctrl_panel.py

@@ -63,36 +63,33 @@ class CtrlPanel(QObject):
         self.trees_ui = trees_ui
         self.NUM_CHANNELS = len(trees_ui)
 
-        self.THERMOSTAT_PARAMETERS = [param_tree for i in range(self.NUM_CHANNELS)]
-
         self.params = [
             Parameter.create(
                 name=f"Thermostat Channel {ch} Parameters",
                 type="group",
                 value=ch,
-                children=self.THERMOSTAT_PARAMETERS[ch],
+                children=param_tree,
             )
             for ch in range(self.NUM_CHANNELS)
         ]
 
-        for i, param in enumerate(self.params):
-            param.channel = i
-
         for i, tree in enumerate(self.trees_ui):
             tree.setHeaderHidden(True)
             tree.setParameters(self.params[i], showTop=False)
-            self.params[i].setValue = self._setValue
-            self.params[i].sigTreeStateChanged.connect(self.send_command)
 
-            self.params[i].child("Save to flash").sigActivated.connect(
-                partial(self.save_settings, i)
+        for ch, param in enumerate(self.params):
+            param.setValue = self._setValue
+            param.sigTreeStateChanged.connect(self.send_command)
+
+            param.child("Save to flash").sigActivated.connect(
+                partial(self.save_settings, ch)
             )
-            self.params[i].child("Load from flash").sigActivated.connect(
-                partial(self.load_settings, i)
+            param.child("Load from flash").sigActivated.connect(
+                partial(self.load_settings, ch)
+            )
+            param.child("PID Config", "PID Auto Tune", "Run").sigActivated.connect(
+                partial(self.pid_auto_tune_request, ch)
             )
-            self.params[i].child(
-                "PID Config", "PID Auto Tune", "Run"
-            ).sigActivated.connect(partial(self.pid_auto_tune_request, i))
 
         self.thermostat.pid_update.connect(self.update_pid)
         self.thermostat.report_update.connect(self.update_report)
@@ -133,7 +130,7 @@ class CtrlPanel(QObject):
     @asyncSlot(object, object)
     async def send_command(self, param, changes):
         """Translates parameter tree changes into thermostat set_param calls"""
-        ch = param.channel
+        ch = param.value()
 
         for inner_param, change, data in changes:
             if change == "value":