Overview

This crate provides a fully-featured code editor widget with syntax highlighting, line numbers, text selection, and comprehensive keyboard navigation for the Iced GUI framework.

Screenshot of the demo application:

Features

• Syntax highlighting for multiple programming languages via syntect
• Line numbers with styled gutter
• Text selection via mouse drag and keyboard shortcuts
• Clipboard operations (copy, paste)
• Undo/Redo with smart command grouping and configurable history
• Custom scrollbars with themed styling
• Focus management for multiple editors
• Native Iced theme support - Automatically adapts to all 23+ built-in Iced themes
• Line wrapping to split long lines
• High performance canvas-based rendering
• Search and replace text

Planned features

• Multiple cursors for simultaneous editing at multiple positions
• Collapse/expand blocks
• Indentation-based or syntax-aware
• Minimap
• Auto-completion

Quick Start

Add this to your Cargo.toml:

[dependencies]
iced = "0.14"
iced-code-editor = "0.3"

Basic Example

Here's a minimal example to integrate the code editor into your Iced application:

use iced::widget::container;
use iced::{Element, Task};
use iced_code_editor::{CodeEditor, Message as EditorMessage};

struct MyApp {
    editor: CodeEditor,
}

#[derive(Debug, Clone)]
enum Message {
    EditorEvent(EditorMessage),
}

impl Default for MyApp {
    fn default() -> Self {
        let code = r#"fn main() {
    println!("Hello, world!");
}
"#;

        Self { editor: CodeEditor::new(code, "rust") }
    }
}

impl MyApp {
    fn update(&mut self, message: Message) -> Task<Message> {
        match message {
            Message::EditorEvent(event) => {
                self.editor.update(&event).map(Message::EditorEvent)
            }
        }
    }

    fn view(&self) -> Element<'_, Message> {
        container(self.editor.view().map(Message::EditorEvent))
            .padding(20)
            .into()
    }
}

fn main() -> iced::Result {
    iced::run(MyApp::update, MyApp::view)
}

Keyboard Shortcuts

The editor supports a comprehensive set of keyboard shortcuts:

Navigation

Editing

Clipboard

Undo/Redo

The editor features smart command grouping - consecutive typing is grouped into single undo operations, while navigation or deletion actions create separate undo points.

Search and Replace

Usage Examples

Changing Themes

The editor uses TokyoNightStorm as the default theme. It automatically adapts to any Iced theme. All 23+ built-in Iced themes are supported:

use iced_code_editor::theme;

// Apply any built-in Iced theme
editor.set_theme(theme::from_iced_theme(&iced::Theme::TokyoNightStorm));
editor.set_theme(theme::from_iced_theme(&iced::Theme::Dracula));
editor.set_theme(theme::from_iced_theme(&iced::Theme::Nord));
editor.set_theme(theme::from_iced_theme(&iced::Theme::CatppuccinMocha));
editor.set_theme(theme::from_iced_theme(&iced::Theme::GruvboxDark));

// Or use any theme from Theme::ALL
for theme in iced::Theme::ALL {
    editor.set_theme(theme::from_iced_theme(theme));
}

Getting and Setting Content

// Get current content
let content = editor.content();

// Check if content has been modified
if editor.is_modified() {
    println!("Editor has unsaved changes");
}

// Mark content as saved (e.g., after saving to file)
editor.mark_saved();

Enable/disable search/replace

The search/replace functionality is enabled by default. It can be toggled on or off. When disabled, search shortcuts (Ctrl+F, Ctrl+H, F3) are ignored and the search dialog is hidden:

// Disable search/replace functionality
editor.set_search_replace_enabled(false);

// Or use builder pattern during initialization
let editor = CodeEditor::new("code", "rs")
    .with_search_replace_enabled(false);

// Check current state
if editor.search_replace_enabled() {
    println!("Search and replace is available");
}

This is useful for read-only editors or when you want to provide your own search interface.

Enable/disable line wrapping

Line wrapping is enabled by default at viewport width. Long lines can be wrapped automatically at the viewport width or at a fixed column:

// Enable line wrapping at viewport width
editor.set_wrap_enabled(true);

// Wrap at a fixed column (e.g., 80 characters)
let editor = CodeEditor::new("code", "rs")
    .with_wrap_enabled(true)
    .with_wrap_column(Some(80));

// Disable wrapping
editor.set_wrap_enabled(false);

// Check current state
if editor.wrap_enabled() {
    println!("Line wrapping is active");
}

When enabled, wrapped lines show a continuation indicator (↪) in the line number gutter.

Enable/disable line numbers

Line numbers are displayed by default. They can be hidden to maximize space for code:

// Hide line numbers
editor.set_line_numbers_enabled(false);

// Or use builder pattern during initialization
let editor = CodeEditor::new("code", "rs")
    .with_line_numbers_enabled(false);

// Show line numbers (default behavior)
editor.set_line_numbers_enabled(true);

// Check current state
if editor.line_numbers_enabled() {
    println!("Line numbers are visible");
}

When disabled, the gutter is completely removed (0px width), providing more horizontal space for code display.

Changing font

The default font of the editor is iced::Font::MONOSPACE. It can be changed with one of the default iced font or by loading a specific font:

let font = iced::font::Family::SansSerif;
self.editor_left.set_font(font);

Themes

The editor natively supports all built-in Iced themes with automatic color adaptation.

Each theme automatically provides:

• Optimized background and foreground colors
• Adaptive gutter (line numbers) styling
• Appropriate text selection colors
• Themed cursor appearance
• Custom scrollbar styling
• Subtle current line highlighting

The editor intelligently adapts colors from the Iced theme palette for optimal code readability.

Supported Languages

The editor supports syntax highlighting for numerous languages via the syntect crate:

• Rust ("rs" or "rust")
• Python ("py" or "python")
• JavaScript/TypeScript ("js", "javascript", "ts", "typescript")
• Lua ("lua")
• C/C++ ("c", "cpp", "c++")
• Java ("java")
• Go ("go")
• HTML/CSS ("html", "css")
• Markdown ("md", "markdown")
• And many more...

For a complete list, refer to the syntect documentation.

Demo Application

A full-featured demo application is included in the demo-app directory, showcasing:

• File operations (open, save, save as)
• Theme switching
• Modified state tracking
• Clipboard operations
• Full keyboard navigation

Run it with:

cargo run --package demo-app --release

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Check docs\DEV.md for more details.

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments

• Built with Iced - A cross-platform GUI library for Rust
• Syntax highlighting powered by syntect