SwiftUI code editor view for iOS and macOS

The CodeEditorView Swift package provides a SwiftUI view implementing a rich code editor for iOS and macOS whose visual style is inspired by Xcode. The currently supported functionality includes syntax highlighting with configurable themes, inline message (warnings, errors, etc) reporting, bracket matching, matching bracket insertion, current line highlighting, and a minimap (only on macOS).

Screenshots of the demo app

This is the default dark theme on macOS. Like in Xcode, messages have got an inline view on the right hand side of the screen, which pops up into a larger overlay to display more information. The minimap on the right provides an outline of the edited text.

The following is the default light theme on iOS. Both line highlighting and the minimap are currently not supported on iOS due to limitations in the iOS version of TextKit. Instead of the line highlight, both the current line (or the current selection range) and lines with messages are indicated with differently coloured line numbers in the gutter.

How to use it

Typical usage of the view is as follows.

struct ContentView: View {
  @State private var text:     String                = "My awesome code..."
  @State private var position: CodeEditor.Position  = CodeEditor.Position()
  @State private var messages: Set<Located<Message>> = Set()

  @Environment(\.colorScheme) private var colorScheme: ColorScheme

  var body: some View {
    CodeEditor(text: $text, position: $position, messages: $messages, language: .swift)
      .environment(\.codeEditorTheme,
                   colorScheme == .dark ? Theme.defaultDark : Theme.defaultLight)
  }
}

Demo app

To see the CodeEditorView in action, have a look at the repo with a cross-platform demo app.

Documentation

For more information, see the package documentation.

Status

I consider this to be pre-release quality. It is sufficient to start building something on it, but it is not yet ready for production. While the CodeEditor view already supports quite a bit of advanced functionality (such as the inline messages and minimap), other components are still quite simple, such as the range of tokens covered by the language configuration. Moreover, performance is still an issue that needs to be addressed. The core archtecture, such as the incremental tokenisation for syntax highlighting, is designed to handle larger files smoothly, but the overall implementation still needs some performance debugging.

License

Distributed under the Apache-2.0 license — see the license file for details.