Iced Code Editor

A high-performance, canvas-based code editor widget for Iced.

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.

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
• Dark & light themes with customizable colors
• High performance canvas-based rendering

Quick Start

Add this to your Cargo.toml:

[dependencies]
iced = "0.14"
iced-code-editor = "0.2"

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.

Usage Examples

Changing Themes

use iced_code_editor::theme;

// Apply dark theme
editor.set_theme(theme::dark(&iced::Theme::Dark));

// Apply light theme
editor.set_theme(theme::light(&iced::Theme::Light));

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();

Cursor Blinking

For cursor blinking animation, subscribe to window frames:

use iced::{Subscription, window};

fn subscription(&self) -> Subscription<Message> {
    window::frames().map(|_| Message::Tick)
}

// In your update function
Message::Tick => {
    self.editor.update(&EditorMessage::Tick).map(Message::EditorEvent)
}

Themes

The editor supports both dark and light themes with customizable colors. Each theme includes:

• Background and foreground colors
• Gutter (line numbers) styling
• Selection colors
• Cursor appearance
• Scrollbar styling

Themes automatically adapt to syntax highlighting for optimal 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.

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