fce-enhanced

An enhanced Flet CodeEditor control with file I/O, search/replace, syntax highlighting, and theme selection.

Built on top of flet-code-editor, adding a full-featured editing experience you can drop into any Flet app or run standalone. This project was created to explore and showcase what's possible with Flet — building a desktop-quality code editor entirely in Python.

Install

pip install fce-enhanced

Or with uv:

uv add fce-enhanced

Development setup

git clone https://github.com/oktl/flet-fce-enhanced.git
cd flet-fce-enhanced
uv sync
source .venv/bin/activate
pre-commit install  # optional, for development

Usage

Run as a standalone app

uvx fce-enhanced                     # open with an empty editor
uvx fce-enhanced path/to/file.py     # open a specific file on launch

During development:

flet run src/fce_enhanced/editor.py                     # open with an empty editor
flet run src/fce_enhanced/editor.py path/to/file.py     # open a specific file on launch

Embed in your own Flet app

EnhancedCodeEditor is a Flet declarative component (@ft.component). Render it with page.render(...) rather than page.add(...).

Minimal example

import flet as ft
from fce_enhanced import EnhancedCodeEditor


def main(page: ft.Page):
    page.title = "My Editor"
    page.render(lambda: EnhancedCodeEditor(expand=True))


ft.run(main)

With configuration

import flet as ft
import flet_code_editor as fce
from fce_enhanced import EnhancedCodeEditor


def main(page: ft.Page):
    page.title = "My Editor"

    def on_title_change(display_path, name, is_dirty):
        page.title = f"{name}{'*' if is_dirty else ''} — My Editor"

    page.render(
        lambda: EnhancedCodeEditor(
            language=fce.CodeLanguage.JAVASCRIPT,
            value="console.log('hello');",
            code_theme=fce.CodeTheme.MONOKAI,
            on_title_change=on_title_change,
            ruff_on_save=False,  # disable ruff (only applies to Python files)
            expand=True,
        )
    )


ft.run(main)

Driving the editor from code

Because a component has no instance to call methods on, pass an EditorHandle to drive it imperatively (open a file, save, etc.) and read its live state:

import sys
import flet as ft
from fce_enhanced import EditorHandle, EnhancedCodeEditor


def main(page: ft.Page):
    handle = EditorHandle()
    initial = sys.argv[1] if len(sys.argv) > 1 else None
    page.render(
        lambda: EnhancedCodeEditor(
            expand=True, handle=handle, initial_path=initial
        )
    )
    # handle.open_path("/path/to/file"), handle.save(), handle.save_as(),
    # handle.close(); read handle.value / handle.dirty / handle.current_path

ft.run(main)

initial_path opens a file automatically on mount — the simplest way to load a file at startup without touching the handle.

Constructor parameters

Driving via EditorHandle

Pass an EditorHandle instance and the component populates it on every render:

handle.open_path("/path/to/file")  # load a file (no dialog)
handle.save()                      # save to current path
handle.save_as()                   # save-as dialog
handle.close()                     # close current file

handle.value          # current editor content (str)
handle.current_path   # path of open file, or None
handle.dirty          # True if there are unsaved changes

Other public exports

The package also exports these utilities from fce_enhanced:

Features

• File operations — Open, Save, Save As, Close, and Revert to Saved with unsaved-changes confirmation
• Native file dialogs — AppleScript dialogs on macOS (with extension filtering), Flet's built-in FilePicker on other platforms
• Search & Replace — Find toolbar with match counting, case sensitivity toggle, whole word matching, prev/next navigation (Enter navigates to next match), Replace and Replace All
• Command Palette — Searchable list of all available commands; type to filter (Cmd+Shift+P / Ctrl+Shift+P)
• Theme Selector — 80+ built-in syntax highlighting themes via a searchable dialog (type to filter)
• Go to Line — Jump to a specific line number (Cmd+G / Ctrl+G)
• Read-Only Mode — Toggle editing lock (Cmd+L / Ctrl+L)
• Font Size Controls — Increase/decrease font size (Cmd+= / Cmd+-)
• Language Selector — Choose syntax highlighting language from a searchable dialog (type to filter); auto-detected on file open, and Save As defaults to the matching file extension
• Language Detection — Automatic syntax highlighting for 40+ file extensions
• Dirty-File Tracking — Visual indicator for unsaved changes
• Diff Pane — Toggleable unified diff view showing changes since last save, with green/red syntax coloring (Cmd+D / Ctrl+D)
• Gutter Toggle — Show or hide the line-number gutter (Shift+Cmd+G / Ctrl+Shift+G)
• Ruff on Save — Auto-runs ruff check --fix and ruff format on .py files; silently skips if ruff is not installed (no error). Remaining lint warnings are shown in a snackbar, and the editor auto-reloads the formatted content. Toggleable from the toolbar
• Status Bar — Line, column, language, and selection info

Keyboard shortcuts

Contributing

Contributions are welcome! See CONTRIBUTING.md for guidelines.

License

MIT

Development

Code style is enforced with ruff via pre-commit hooks:

pre-commit run --all-files

Run tests:

pytest

Built With

• Flet — Build multi-platform apps in Python powered by Flutter
• flet-code-editor — Code editor control for Flet with syntax highlighting
• ruff — Fast Python linter and formatter