fix(dark mode button): fixed dark mode button state for external updates, including auto

bec_widgets/utils/colors.py

@@ -8,7 +8,7 @@ import pyqtgraph as pg
 from bec_qthemes._os_appearance.listener import OSThemeSwitchListener
 from pydantic_core import PydanticCustomError
 from qtpy.QtGui import QColor
-from qtpy.QtWidgets import QApplication
+from qtpy.QtWidgets import QApplication, QPushButton, QToolButton
 
 
 def get_theme_palette():
@@ -56,6 +56,17 @@ def apply_theme(theme: Literal["dark", "light"]):
     for pg_widget in children:
         pg_widget.setBackground("k" if theme == "dark" else "w")
 
+    dark_mode_buttons = [
+        button
+        for button in app.topLevelWidgets()
+        if hasattr(button, "dark_mode_enabled")
+        and hasattr(button, "mode_button")
+        and isinstance(button.mode_button, (QPushButton, QToolButton))
+    ]
+
+    for button in dark_mode_buttons:
+        button.dark_mode_enabled = theme == "dark"
+        button.update_mode_button()
     # now define stylesheet according to theme and apply it
     style = bec_qthemes.load_stylesheet(theme)
     app.setStyleSheet(style)

bec_widgets/widgets/dark_mode_button/dark_mode_button.py

@@ -1,6 +1,6 @@
 from bec_qthemes import material_icon
 from qtpy.QtCore import Property, Qt, Slot
-from qtpy.QtWidgets import QHBoxLayout, QPushButton, QToolButton, QWidget
+from qtpy.QtWidgets import QApplication, QHBoxLayout, QPushButton, QToolButton, QWidget
 
 from bec_widgets.utils.bec_widget import BECWidget
 from bec_widgets.utils.colors import set_theme
@@ -27,17 +27,31 @@ class DarkModeButton(BECWidget, QWidget):
         self.layout.setContentsMargins(0, 0, 0, 0)
         self.layout.setAlignment(Qt.AlignmentFlag.AlignVCenter)
 
-        icon = material_icon("dark_mode", size=(20, 20), convert_to_pixmap=False)
         if toolbar:
-            self.mode_button = QToolButton(icon=icon)
+            self.mode_button = QToolButton()
         else:
-            self.mode_button = QPushButton(icon=icon)
+            self.mode_button = QPushButton()
+
+        self.dark_mode_enabled = self._get_qapp_dark_mode_state()
         self.update_mode_button()
         self.mode_button.clicked.connect(self.toggle_dark_mode)
         self.layout.addWidget(self.mode_button)
         self.setLayout(self.layout)
         self.setFixedSize(40, 40)
 
+    def _get_qapp_dark_mode_state(self) -> bool:
+        """
+        Get the dark mode state from the QApplication.
+
+        Returns:
+            bool: True if dark mode is enabled, False otherwise.
+        """
+        qapp = QApplication.instance()
+        if hasattr(qapp, "theme") and qapp.theme["theme"] == "dark":
+            return True
+
+        return False
+
     @Property(bool)
     def dark_mode_enabled(self) -> bool:
         """
@@ -72,8 +86,10 @@ class DarkModeButton(BECWidget, QWidget):
 if __name__ == "__main__":
     from qtpy.QtWidgets import QApplication
 
-    app = QApplication([])
+    from bec_widgets.utils.colors import set_theme
 
+    app = QApplication([])
+    set_theme("auto")
     w = DarkModeButton()
     w.show()
 

tests/unit_tests/test_dark_mode_button.py

@@ -3,6 +3,7 @@ from unittest import mock
 import pytest
 from qtpy.QtCore import Qt
 
+from bec_widgets.utils.colors import set_theme
 from bec_widgets.widgets.dark_mode_button.dark_mode_button import DarkModeButton
 
 # pylint: disable=unused-import
@@ -19,6 +20,7 @@ def dark_mode_button(qtbot, mocked_client):
     button = DarkModeButton(client=mocked_client)
     qtbot.addWidget(button)
     qtbot.waitExposed(button)
+    set_theme("light")
     yield button