refactor(mouse wheel): Refactor mouse wheel handling in comboboxes

Add pytests
Fix pylint
Fix mypy

Author: amilcarlucas

ardupilot_methodic_configurator/frontend_tkinter_component_editor.py

@@ -18,7 +18,7 @@
 from logging import basicConfig as logging_basicConfig
 from logging import getLevelName as logging_getLevelName
 from tkinter import ttk
-from typing import Optional, Union
+from typing import Union
 
 from ardupilot_methodic_configurator import _, __version__
 from ardupilot_methodic_configurator.backend_filesystem import LocalFilesystem
@@ -29,6 +29,7 @@
     FC_CONNECTION_TYPE_PATHS,
 )
 from ardupilot_methodic_configurator.frontend_tkinter_component_editor_base import ComponentEditorWindowBase
+from ardupilot_methodic_configurator.frontend_tkinter_pair_tuple_combobox import setup_combobox_mousewheel_handling
 
 # from ardupilot_methodic_configurator.frontend_tkinter_show import show_tooltip
 from ardupilot_methodic_configurator.frontend_tkinter_show import show_error_message, show_warning_message
@@ -179,35 +180,16 @@ def on_validate_combobox(event: tk.Event) -> bool:
             cb.bind("<Return>", on_validate_combobox)
             cb.bind("<ButtonRelease>", on_validate_combobox)
 
-            # Prevent mouse wheel from changing value when dropdown is not open
-            def handle_mousewheel(_event: tk.Event, widget: tk.Widget = cb) -> Optional[str]:
-                # Check if dropdown is open by examining the combobox's state
-                dropdown_is_open = getattr(widget, "dropdown_is_open", False)
-                if not dropdown_is_open:
-                    widget.master.event_generate("<MouseWheel>", delta=_event.delta)  # type: ignore[attr-defined]
-                    return "break"  # Prevent default behavior
-                return None  # Allow default behavior when dropdown is open
-
-            # Set flag when dropdown opens or closes
-            def dropdown_opened(_event: tk.Event, widget: tk.Widget = cb) -> None:
-                widget.dropdown_is_open = True  # type: ignore[attr-defined]
-
-            def dropdown_closed(_event: tk.Event, widget: tk.Widget = cb) -> None:
-                widget.dropdown_is_open = False  # type: ignore[attr-defined]
-
-            # Initialize the flag
-            cb.dropdown_is_open = False  # type: ignore[attr-defined]
-
-            # Bind to events for dropdown opening and closing
-            cb.bind("<<ComboboxDropdown>>", dropdown_opened)
-            cb.bind(
-                "<FocusOut>",
-                lambda e, p=path: (dropdown_closed(e), self._validate_combobox(e, p)),  # type: ignore[misc,func-returns-value]
-            )
-            # Bind mouse wheel events
-            cb.bind("<MouseWheel>", handle_mousewheel)  # Windows mouse wheel
-            cb.bind("<Button-4>", handle_mousewheel)  # Linux mouse wheel up
-            cb.bind("<Button-5>", handle_mousewheel)  # Linux mouse wheel down
+            # Set up mouse wheel handling to prevent unwanted value changes
+            setup_combobox_mousewheel_handling(cb)
+
+            # Override the FocusOut binding to also handle validation
+            def combined_focus_out(event: tk.Event) -> None:
+                # First handle the dropdown closing logic (already done by setup function)
+                # Then handle validation
+                self._validate_combobox(event, path)
+
+            cb.bind("<FocusOut>", combined_focus_out, add="+")
 
             if path in FC_CONNECTION_TYPE_PATHS:
                 cb.bind(  # immediate update of Protocol combobox choices after changing connection Type selection

ardupilot_methodic_configurator/frontend_tkinter_pair_tuple_combobox.py

@@ -22,12 +22,54 @@
 from platform import system as platform_system
 from sys import exit as sys_exit
 from tkinter import Label, Toplevel, ttk
-from typing import Union
+from typing import Optional, Union
 
 from ardupilot_methodic_configurator import _
 from ardupilot_methodic_configurator.common_arguments import add_common_arguments
 from ardupilot_methodic_configurator.frontend_tkinter_autoresize_combobox import update_combobox_width
 
+
+def setup_combobox_mousewheel_handling(combobox: ttk.Combobox) -> None:
+    """
+    Set up mouse wheel handling for a combobox to prevent value changes when scrolling.
+
+    This function adds event bindings to prevent the combobox value from changing
+    when the user scrolls the mouse wheel over it while the dropdown is closed.
+    When the dropdown is closed, the mouse wheel event is propagated to the parent
+    widget to allow normal scrolling behavior in the containing widget.
+
+    Args:
+        combobox: The ttk.Combobox widget to configure
+
+    """
+    # Track dropdown state to control mouse wheel behavior
+    combobox.dropdown_is_open = False  # type: ignore[attr-defined]
+
+    def handle_mousewheel(event: tk.Event) -> Optional[str]:
+        """Handle mouse wheel events - propagate to parent when dropdown is closed."""
+        if not combobox.dropdown_is_open:  # type: ignore[attr-defined]
+            # Propagate the wheel event to the parent widget
+            combobox.master.event_generate("<MouseWheel>", delta=event.delta)
+            return "break"  # Prevent default combobox behavior
+        return None  # Allow default behavior when dropdown is open
+
+    def dropdown_opened(_event: Optional[tk.Event] = None) -> None:
+        """Mark dropdown as open."""
+        combobox.dropdown_is_open = True  # type: ignore[attr-defined]
+
+    def dropdown_closed(_event: Optional[tk.Event] = None) -> None:
+        """Mark dropdown as closed."""
+        combobox.dropdown_is_open = False  # type: ignore[attr-defined]    # Bind mouse wheel events (Windows and Linux)
+
+    combobox.bind("<MouseWheel>", handle_mousewheel, add="+")
+    combobox.bind("<Button-4>", handle_mousewheel, add="+")
+    combobox.bind("<Button-5>", handle_mousewheel, add="+")
+
+    # Track dropdown open/close events
+    combobox.bind("<<ComboboxDropdown>>", dropdown_opened, add="+")
+    combobox.bind("<FocusOut>", dropdown_closed, add="+")
+
+
 # SPDX-SnippetBegin
 # SPDX-License-Identifier: MPL-2.0
 # SPDX-SnippetCopyrightText: 2022 geraldew
@@ -58,6 +100,9 @@ def __init__(
         self.set_entries_tuple(list_pair_tuple, selected_element)
         self.bind("<Configure>", self.on_combo_configure, add="+")
 
+        # Apply mouse wheel handling to this combobox instance
+        setup_combobox_mousewheel_handling(self)
+
     def set_entries_tuple(self, list_pair_tuple: list[tuple[str, str]], selected_element: Union[None, str]) -> None:
         if isinstance(list_pair_tuple, list):
             for tpl in list_pair_tuple:

ardupilot_methodic_configurator/frontend_tkinter_parameter_editor_table.py

@@ -16,7 +16,7 @@
 from platform import system as platform_system
 from sys import exit as sys_exit
 from tkinter import messagebox, ttk
-from typing import Optional, Union
+from typing import Union
 
 from ardupilot_methodic_configurator import _
 from ardupilot_methodic_configurator.annotate_params import Par
@@ -30,7 +30,10 @@
 from ardupilot_methodic_configurator.data_model_configuration_step import ConfigurationStepProcessor
 from ardupilot_methodic_configurator.frontend_tkinter_base_window import BaseWindow
 from ardupilot_methodic_configurator.frontend_tkinter_entry_dynamic import EntryWithDynamicalyFilteredListbox
-from ardupilot_methodic_configurator.frontend_tkinter_pair_tuple_combobox import PairTupleCombobox
+from ardupilot_methodic_configurator.frontend_tkinter_pair_tuple_combobox import (
+    PairTupleCombobox,
+    setup_combobox_mousewheel_handling,
+)
 from ardupilot_methodic_configurator.frontend_tkinter_rich_text import get_widget_font_family_and_size
 from ardupilot_methodic_configurator.frontend_tkinter_scroll_frame import ScrollFrame
 from ardupilot_methodic_configurator.frontend_tkinter_show import show_tooltip
@@ -358,37 +361,6 @@ def _update_combobox_style_on_selection(  # pylint: disable=too-many-arguments,
         event.width = NEW_VALUE_WIDGET_WIDTH
         combobox_widget.on_combo_configure(event)
 
-    def _setup_combobox_mousewheel_handling(self, combobox: PairTupleCombobox) -> None:
-        """Set up mouse wheel handling for combobox to prevent unwanted value changes."""
-
-        # Prevent mouse wheel from changing value when dropdown is not open
-        def handle_mousewheel(_event: tk.Event, widget: tk.Widget = combobox) -> Optional[str]:
-            # Check if dropdown is open by examining the combobox's state
-            dropdown_is_open = getattr(widget, "dropdown_is_open", False)
-            if not dropdown_is_open:
-                widget.master.event_generate("<MouseWheel>", delta=_event.delta)
-                return "break"  # Prevent default behavior
-            return None  # Allow default behavior when dropdown is open
-
-        # Set flag when dropdown opens or closes
-        def dropdown_opened(_event: tk.Event, widget: tk.Widget = combobox) -> None:
-            widget.dropdown_is_open = True  # type: ignore[attr-defined]
-
-        def dropdown_closed(_event: tk.Event, widget: tk.Widget = combobox) -> None:
-            widget.dropdown_is_open = False  # type: ignore[attr-defined]
-
-        # Initialize the flag
-        combobox.dropdown_is_open = False  # type: ignore[attr-defined]
-
-        # Bind to events for dropdown opening and closing
-        combobox.bind("<<ComboboxDropdown>>", dropdown_opened)
-        combobox.bind("<FocusOut>", dropdown_closed, "+")
-
-        # Bind mouse wheel events
-        combobox.bind("<MouseWheel>", handle_mousewheel)  # Windows mouse wheel
-        combobox.bind("<Button-4>", handle_mousewheel)  # Linux mouse wheel up
-        combobox.bind("<Button-5>", handle_mousewheel)  # Linux mouse wheel down
-
     @staticmethod
     def _update_new_value_entry_text(new_value_entry: ttk.Entry, param: ArduPilotParameter) -> None:
         """Update the new value entry text and style."""
@@ -442,7 +414,7 @@ def _create_new_value_entry(  # pylint: disable=too-many-statements # noqa: PLR0
             )
 
             # Set up mouse wheel handling to prevent unwanted value changes
-            self._setup_combobox_mousewheel_handling(new_value_entry)
+            setup_combobox_mousewheel_handling(new_value_entry)
         else:
             new_value_entry = ttk.Entry(self.view_port, width=NEW_VALUE_WIDGET_WIDTH + 1, justify=tk.RIGHT)
             self._update_new_value_entry_text(new_value_entry, param)