Application Entry and Main Window

This document describes the responsibilities and structure of the MainWindow class, which serves as the central controller of the user interface. It manages tabs, toolbars, menus, layout state, and forwards loaded data to the active tab. While it plays a crucial structural role, it delegates all domain-specific logic (e.g. fitting, plotting) to components like FitTab.

The class is currently very large and tightly coupled. It would benefit from a future refactoring to isolate responsibilities more clearly.

Role of MainWindow

  • Hosts all top-level UI components (toolbar, menus, tabs)
  • Creates and switches between tabs (FitTab, etc.)
  • Manages global application layout and dock visibility
  • Handles file I/O operations through menu actions
  • Injects loaded data into the current tab

System Diagram

graph TD Main[MainWindow] Fit[FitTab] Plot[PlotWidget] Toolbar[Toolbar] Config[ConfigManager] Loader[DataLoader] MenuBar[Menu Bar] Docks[Dock Widgets] Main --> Fit Main --> Toolbar Main --> MenuBar Main --> Config Main --> Loader Fit --> Plot Fit --> Docks

UI Initialization

class MainWindow(QMainWindow):
    def __init__(self):
        self.config = ConfigManager()
        self.setFixedSize(...)
        self._init_interface()

All core components (menu bar, toolbar, tab container, status bar) are initialized once in _init_interface(). A first FitTab is created by default.

Tab Lifecycle

Tabs are created using add_fit_tab() and inserted into the central QTabWidget. When the user switches tabs, the View menu is rebuilt to reflect the correct dock widgets and toolbar state.

plot_widget = PlotWidget(self)
new_tab = FitTab(self, plot_widget)
self.tabs.addTab(new_tab, new_tab.get_fit_name())

Dock Visibility and View Menu

Each tab manages its own docks (fit panel, plot, results...). The MainWindow maintains a mapping of visible docks and their associated menu actions for each tab:

self.view_actions_per_tab[tab] = {
    "Fit Formula": (action, dock),
    ...
}

When switching tabs, the view menu is cleared and rebuilt accordingly.

Grouped Methods in MainWindow

The table below categorizes each method by role.

1. Initialization

Method Role
__init__() Reads config and initializes main UI layout
_init_interface() Builds toolbar, menus, status bar, tab system

2. Menu Setup

Method Role
_init_file_menu() Creates File menu: Load, Export, Exit
_init_fits_menu() Adds New/Close Fit actions
_init_view_menu() Connects menu items to dock visibility

3. Tab Management

Method Role
add_fit_tab() Creates a new FitTab and activates it
get_current_fit_tab() Returns active FitTab or None
close_fit_tab(index) Closes tab at the given index
rename_tab(index) Renames tab via inline QLineEdit
duplicate_tab(index) Copies data, formula, and options to new tab

4. View State & Docks

Method Role
_update_view_menu_for_current_tab() Rebuilds View menu when tab changes
_init_view_menu() Registers visibility toggles for tab docks
restore_default_view() Restores all docks in current tab
_snapshot_dock_states_before_switch(index) Saves dock state before tab switch

5. Toolbar State

Method Role
enable_toolbar_buttons(enabled) Enables/disables toolbar buttons after a fit
_snapshot_toolbar_state(tab) Records which toolbar buttons are enabled
_restore_toolbar_state(tab) Re-applies the saved toolbar state

6. Data I/O

Method Role
load_data_from_menu() Loads data via file dialog
load_previous_data() Loads last accessed file
_inject_data_into_tab() Injects DataFrame into current tab
unload_data() Clears data from the current tab
export_data() Exports current data to CSV

7. Status

Method Role
show_status() Displays message in the status bar

8. App Entry Point

Method Role
main() Entry point to launch the app

Connected Modules

Component Description
FitTab Main per-dataset fit interface
Toolbar Global toolbar shared across tabs
PlotWidget Rendering backend used by each tab
ConfigManager Manages saved layout, window size
DataLoader Handles file selection and parsing

Notes

This class is currently responsible for too many aspects of the interface: tab lifecycle, dock logic, toolbar state, file handling, and persistence. Future work could separate:

  • Tab creation logic
  • Menu construction
  • Toolbar state tracking
  • Layout state into a controller class