move resize event handling to the generic Window class

gui_handler.py

@@ -6,10 +6,11 @@ app = QtWidgets.QApplication([])
 #TODO: Implement separate editor, terminal and main_window classes using Window as a parent
 
 class Window(QtWidgets.QMainWindow):
-    def __init__(self, size=(640, 480), title="Concorde"):
+    def __init__(self, size=(640, 480), title="Concorde", on_resize=lambda event: None):
         super().__init__()
         self.setWindowTitle(title)
         self.resize(size[0], size[1])
+        self.__on_resize = on_resize
 
     def __del__(self):
         #TODO: whatever needs to be done here
@@ -26,6 +27,9 @@ class Window(QtWidgets.QMainWindow):
     def set_size(self, size_x, size_y):
         self.resize(size_x, size_y)
 
+    def on_resize(self, function):
+        self.__on_resize = function
+
     def update_menus(self, menu_dict, menu=None):
         # if not a sub menu
         if menu == None:
@@ -52,6 +56,11 @@ class Window(QtWidgets.QMainWindow):
                 menu_item = menu.addAction(entry)
                 menu_item.triggered.connect(menu_dict[entry])
 
+    # Toolkit specific! Do not use outside gui_handler.
+    def resizeEvent(self, event):
+        self.__on_resize(event)
+
+
 class Editor(Window):
     def __init__(self, size=(640, 480)):
         super().__init__(size, "Editor")
@@ -72,8 +81,7 @@ class Editor(Window):
 
         self.setLayout(layout)
         
-    def resizeEvent(self, event):
-        self.set_size(event.size().width(), event.size().height())
+        super().on_resize(lambda event: self.set_size(event.size().width(), event.size().height()))
 
     #FIXME: This function is inherently flawed because it doesn't take the
     #       actual height of the usable area inside the window into account.