Statusbar: Add custom widgets to the default layout instead of replac…

…ing it

That will allow developers to have an icon, label and spinner for their
widgets, in case they need them.

spyder/api/widgets/status.py

@@ -23,9 +23,12 @@ class StatusBarWidget(QWidget, SpyderWidgetMixin):
     """
     Base class for status bar widgets.
 
-    These widgets consist of an icon, a label and (optionally) a
-    spinner. However, you can use any QWidget in the status bar by
-    passing its class to CUSTOM_WIDGET_CLASS.
+    These widgets consist by default of an icon, a label and a spinner,
+    which are organized from left to right on that order.
+
+    You can also add any other QWidget to this layout by setting the
+    CUSTOM_WIDGET_CLASS class attribute. It'll be put between the label
+    and the spinner.
     """
 
     ID = None
@@ -35,9 +38,7 @@ class StatusBarWidget(QWidget, SpyderWidgetMixin):
 
     CUSTOM_WIDGET_CLASS = None
     """
-    Custom widget class to use instead of the default widget layout.
-    This will completely override the widget API, which won't have
-    any effect.
+    Custom widget class to add to the default layout.
     """
 
     sig_option_changed = Signal(str, object)
@@ -52,43 +53,79 @@ class StatusBarWidget(QWidget, SpyderWidgetMixin):
     """
 
     def __init__(self, parent=None, show_spinner=False):
-        """Status bar widget base."""
+        """
+        Base class for status bar widgets.
+
+        These are composed of the following widgets, which are arranged
+        in a QHBoxLayout from left to right:
+
+        * Icon
+        * Label
+        * Custom QWidget (optional)
+        * Spinner (optional)
+
+        Parameters
+        ----------
+        show_spinner: bool
+            Show a spinner.
+
+        Notes
+        -----
+        1. To use an icon, you need to redefine the ``get_icon`` method.
+        2. To use a label, you need to call ``set_value``.
+        """
         super().__init__(parent)
         self._parent = parent
         self.show_spinner = show_spinner
+
+        self.value = None
+        self.label_icon = None
+        self.label_value = None
         self.spinner = None
+        self.custom_widget = None
 
-        if self.CUSTOM_WIDGET_CLASS:
-            if not issubclass(self.CUSTOM_WIDGET_CLASS, QWidget):
-                raise SpyderAPIError(
-                    'Any custom status widget must subclass QWidget!'
-                )
-            self.custom_widget = self.CUSTOM_WIDGET_CLASS(parent)
-            self.set_custom_layout()
-        else:
-            self.custom_widget = None
-            self.set_default_layout()
+        self.set_layout()
 
-    def set_default_layout(self):
+    def set_layout(self):
         """Set layout for default widgets."""
-        # Variables
-        self.value = None
-
-        # Widget
+        # Icon
         self._icon = self.get_icon()
         self._pixmap = None
         self._icon_size = QSize(16, 16)  # Should this be adjustable?
         self.label_icon = QLabel()
+        self.set_icon()
+
+        # Label
         self.label_value = QLabel()
+        self.set_value('')
+
+        # See spyder-ide/spyder#9044.
+        self.text_font = QFont(QFont().defaultFamily(), weight=QFont.Normal)
+        self.label_value.setAlignment(Qt.AlignRight | Qt.AlignVCenter)
+        self.label_value.setFont(self.text_font)
+
+        # Custom widget
+        if self.CUSTOM_WIDGET_CLASS:
+            if not issubclass(self.CUSTOM_WIDGET_CLASS, QWidget):
+                raise SpyderAPIError(
+                    'Any custom status widget must subclass QWidget!'
+                )
+            self.custom_widget = self.CUSTOM_WIDGET_CLASS(self._parent)
+
+        # Spinner
         if self.show_spinner:
             self.spinner = create_waitspinner(size=14, parent=self)
+            self.spinner.hide()
 
         # Layout setup
         layout = QHBoxLayout(self)
         layout.setSpacing(0)  # Reduce space between icon and label
         layout.addWidget(self.label_icon)
         layout.addWidget(self.label_value)
 
+        if self.custom_widget:
+            layout.addWidget(self.custom_widget)
+
         if self.show_spinner:
             layout.addWidget(self.spinner)
             self.spinner.hide()
@@ -101,45 +138,12 @@ def set_default_layout(self):
         layout.setContentsMargins(0, 0, 0, 0)
         layout.setAlignment(Qt.AlignVCenter)
 
-        # Widget setup
-        self.set_icon()
-
-        # See spyder-ide/spyder#9044.
-        self.text_font = QFont(QFont().defaultFamily(), weight=QFont.Normal)
-        self.label_value.setAlignment(Qt.AlignRight)
-        self.label_value.setFont(self.text_font)
-
         # Setup
-        self.set_value('')
         self.update_tooltip()
 
-    def set_custom_layout(self):
-        """Set layout for custom widgets."""
-        if self.show_spinner:
-            self.spinner = create_waitspinner(size=14, parent=self)
-
-        layout = QHBoxLayout(self)
-        layout.setSpacing(0)
-        layout.addWidget(self.custom_widget)
-
-        if self.show_spinner:
-            layout.addWidget(self.spinner)
-            self.spinner.hide()
-
-        if is_dark_interface():
-            layout.addSpacing(0)
-        else:
-            layout.addSpacing(10)
-
-        layout.setContentsMargins(0, 0, 0, 0)
-        layout.setAlignment(Qt.AlignVCenter)
-
     # ---- Status bar widget API
     def set_icon(self):
         """Set the icon for the status bar widget."""
-        if self.custom_widget:
-            return
-
         icon = self._icon
         self.label_icon.setVisible(icon is not None)
         if icon is not None and isinstance(icon, QIcon):
@@ -148,17 +152,11 @@ def set_icon(self):
 
     def set_value(self, value):
         """Set formatted text value."""
-        if self.custom_widget:
-            return
-
         self.value = value
         self.label_value.setText(value)
 
     def update_tooltip(self):
         """Update tooltip for widget."""
-        if self.custom_widget:
-            return
-
         tooltip = self.get_tooltip()
         if tooltip:
             self.label_value.setToolTip(tooltip)

spyder/plugins/statusbar/widgets/tests/test_status.py

@@ -69,6 +69,9 @@ class CustomStatusBarWidget(StatusBarWidget):
     ID = 'custom_status'
     CUSTOM_WIDGET_CLASS = MyComboBox
 
+    def get_icon(self):
+        return self.create_icon('environment')
+
 
 def test_status_bar_widget_signal(status_bar, qtbot):
     plugin, window = status_bar
@@ -92,6 +95,7 @@ def test_custom_widget(status_bar, qtbot):
 
     # Add widget to status bar
     w = CustomStatusBarWidget(window)
+    w.set_value('Options: ')
     plugin.add_status_widget(w)
     # qtbot.stop()