moninj: handler create, delete widgets

artiq/dashboard/moninj.py

@@ -115,14 +115,12 @@ class _TTLHandler:
         self.channel = channel
         self.force_out = force_out
         self.set_mode = dm.ttl_set_mode
+        self.title = title
         self.cur_level = False
         self.cur_oe = False
         self.cur_override = False
         self.cur_override_level = False
-        self.widget = _TTLWidget(title)
-        self.widget.override_toggled.connect(self.override_toggled)
-        self.widget.level_toggled.connect(self.level_toggled)
-        self.refresh_display()
+        self.widget = None
 
     def override_toggled(self, override):
         if override:
@@ -141,12 +139,23 @@ class _TTLHandler:
                 self.set_mode(self.channel, "0")
 
     def refresh_display(self):
-        level = self.cur_override_level if self.cur_override else self.cur_level
-        oe = self.cur_oe or self.force_out
-        self.widget.setValueText(self.cur_override, level)
-        self.widget.setDirectionText(oe)
-        with QtCore.QSignalBlocker(self.widget):
-            self.widget.setButtonsState(self.cur_override, self.cur_level)
+        if self.widget is not None:
+            level = self.cur_override_level if self.cur_override else self.cur_level
+            oe = self.cur_oe or self.force_out
+            self.widget.setValueText(self.cur_override, level)
+            self.widget.setDirectionText(oe)
+            with QtCore.QSignalBlocker(self.widget):
+                self.widget.setButtonsState(self.cur_override, self.cur_level)
+
+    def delete_widget(self):
+        self.widget.deleteLater()
+        self.widget = None
+
+    def create_widget(self):
+        self.widget = _TTLWidget(self.title)
+        self.widget.override_toggled.connect(self.override_toggled)
+        self.widget.level_toggled.connect(self.level_toggled)
+        self.refresh_display()
 
     def sort_key(self):
         return self.channel
@@ -282,6 +291,7 @@ class _DDSHandler:
     def __init__(self, dm, title, bus_channel, channel, dds_type,
                  ref_clk, cpld=None, pll=1, clk_div=0):
         self.dm = dm
+        self.title = title
         self.bus_channel = bus_channel
         self.channel = channel
         self.cur_frequency = 0
@@ -305,7 +315,10 @@ class _DDSHandler:
                 raise NotImplementedError
             sysclk = ref_clk / clk_mult[clk_div] * pll
             self.ftw_per_hz = 1 / sysclk * max_freq
-        self.widget = _DDSWidget(title, self.is_urukul)
+        self.widget = None
+
+    def create_widget(self):
+        self.widget = _DDSWidget(self.title, self.is_urukul)
         self.widget.apply_changes.connect(self.apply_changes)
         self.widget.off_clicked.connect(self.off_clicked)
         self.widget.set_clicked.connect(self.set_clicked)
@@ -319,8 +332,13 @@ class _DDSHandler:
     def _ftw_to_freq(self, ftw):
         return ftw / self.ftw_per_hz
 
+    def delete_widget(self):
+        self.widget.deleteLater()
+        self.widget = None
+
     def refresh_display(self):
-        self.widget.set_value(self.cur_frequency / 1e6)
+        if self.widget is not None:
+            self.widget.set_value(self.cur_frequency / 1e6)
 
     def apply_changes(self):
         self.widget.set_page(0)
@@ -370,14 +388,23 @@ class _DACWidget(QtWidgets.QFrame):
 
 class _DACHandler:
     def __init__(self, dm, spi_channel, channel, title):
-        self.widget = _DACWidget(channel, title)
+        self.widget = None
         self.cur_value = 0
         self.spi_channel = spi_channel
         self.channel = channel
+        self.title = title
+
+    def create_widget(self):
+        self.widget = _DACWidget(self.channel, self.title)
         self.refresh_display()
 
+    def delete_widget(self):
+        self.widget.deleteLater()
+        self.widget = None
+
     def refresh_display(self):
-        self.widget.set_value(self.cur_value * 100 / 2**16)
+        if self.widget is not None:
+            self.widget.set_value(self.cur_value * 100 / 2**16)
 
     def sort_key(self):
         return (self.spi_channel, self.channel)
@@ -484,17 +511,17 @@ class _DeviceManager:
 
             if isinstance(handler, _TTLHandler):
                 self.setup_ttl_monitoring(False, handler.channel)
-                handler.widget.deleteLater()
+                handler.delete_widget()
                 del self.ttl_handlers[handler.channel]
                 self.ttl_cb()
             elif isinstance(handler, _DDSHandler):
                 self.setup_dds_monitoring(False, handler.bus_channel, handler.channel)
-                handler.widget.deleteLater()
+                handler.delete_widget()
                 del self.dds_handlers[(handler.bus_channel, handler.channel)]
                 self.dds_cb()
             elif isinstance(handler, _DACHandler):
                 self.setup_dac_monitoring(False, handler.spi_channel, handler.channel)
-                handler.widget.deleteLater()
+                handler.delete_widget()
                 del self.dac_handlers[(handler.spi_channel, handler.channel)]
                 self.dac_cb()
             else:
@@ -502,6 +529,7 @@ class _DeviceManager:
 
         for to_add in description - self.description:
             handler = to_add.cls(self, *to_add.arguments)
+            handler.create_widget()
             if to_add.comment is not None:
                 handler.widget.setToolTip(to_add.comment)
             self.handlers_by_uid[to_add.uid] = handler