fix: thread-safe hotkey handling

- Add HotkeyHandler class with pyqtSignal
- Fix QMetaObject.invokeMethod error
- Proper thread safety for keyboard hotkeys

projects/EU-Utility/core/main.py

@@ -15,7 +15,7 @@ if str(project_root) not in sys.path:
 
 try:
     from PyQt6.QtWidgets import QApplication
-    from PyQt6.QtCore import Qt
+    from PyQt6.QtCore import Qt, QObject, pyqtSignal
     PYQT_AVAILABLE = True
 except ImportError:
     PYQT_AVAILABLE = False
@@ -35,6 +35,11 @@ from core.plugin_manager import PluginManager
 from core.overlay_window import OverlayWindow
 
 
+class HotkeyHandler(QObject):
+    """Signal bridge for thread-safe hotkey handling."""
+    toggle_signal = pyqtSignal()
+
+
 class EUUtilityApp:
     """Main application controller."""
     
@@ -42,6 +47,7 @@ class EUUtilityApp:
         self.app = None
         self.overlay = None
         self.plugin_manager = None
+        self.hotkey_handler = None
         
     def run(self):
         """Start the application."""
@@ -53,6 +59,9 @@ class EUUtilityApp:
         if hasattr(Qt, 'AA_EnableHighDpiScaling'):
             self.app.setAttribute(Qt.ApplicationAttribute.AA_EnableHighDpiScaling)
         
+        # Create hotkey handler (must be in main thread)
+        self.hotkey_handler = HotkeyHandler()
+        
         # Initialize plugin manager
         print("Loading plugins...")
         self.plugin_manager = PluginManager(None)
@@ -62,6 +71,9 @@ class EUUtilityApp:
         self.overlay = OverlayWindow(self.plugin_manager)
         self.plugin_manager.overlay = self.overlay
         
+        # Connect hotkey signal
+        self.hotkey_handler.toggle_signal.connect(self._on_toggle_signal)
+        
         # Setup global hotkey
         self._setup_hotkey()
         
@@ -75,20 +87,20 @@ class EUUtilityApp:
         """Setup global hotkey."""
         if KEYBOARD_AVAILABLE:
             try:
-                keyboard.add_hotkey('ctrl+shift+u', self._toggle_overlay)
+                keyboard.add_hotkey('ctrl+shift+u', self._on_hotkey_pressed)
             except Exception as e:
                 print(f"Failed to register hotkey: {e}")
     
-    def _toggle_overlay(self):
-        """Toggle overlay visibility."""
+    def _on_hotkey_pressed(self):
+        """Called when hotkey is pressed (from keyboard thread)."""
+        # Emit signal to main thread
+        if self.hotkey_handler:
+            self.hotkey_handler.toggle_signal.emit()
+    
+    def _on_toggle_signal(self):
+        """Handle toggle signal in main thread."""
         if self.overlay:
-            # Use Qt's thread-safe method
-            from PyQt6.QtCore import QMetaObject, Qt
-            QMetaObject.invokeMethod(
-                self.overlay,
-                "toggle_overlay",
-                Qt.ConnectionType.QueuedConnection
-            )
+            self.overlay.toggle_overlay()
 
 
 def main():