Editor Focus Notifier

A VS Code extension that detects when you enter or leave the text editor area and runs configurable shell commands on those transitions.

Features

• Detects focus state transitions between editor and non-editor areas
• Runs custom shell commands when entering/leaving editor focus
• Useful for integrating with external tools like Hammerspoon, Karabiner-Elements, and BetterTouchTool

Use Case

The primary use case is to notify external tools so they can activate UI enhancements and event modifications using those tools' capabilities.

Configuration

Configure the extension through VS Code settings:

• editorFocusNotifier.enable: Enable or disable the extension (default: true)
• editorFocusNotifier.onEnterEditorCommand: Shell command to run when entering editor focus state
• editorFocusNotifier.onLeaveEditorCommand: Shell command to run when leaving editor focus state

Example Configuration With Hammerspoon

{
  "editorFocusNotifier.onEnterEditorCommand": "open \"hammerspoon://vscode-focus?mode=editor\"",
  "editorFocusNotifier.onLeaveEditorCommand": "open \"hammerspoon://vscode-focus?mode=other\""
}

Example Configuration With Karabiner-Elements

{
  "editorFocusNotifier.onEnterEditorCommand": "'/Library/Application Support/org.pqrs/Karabiner-Elements/bin/karabiner_cli' --select-profile 'VSCodeEditor'",
  "editorFocusNotifier.onLeaveEditorCommand": "'/Library/Application Support/org.pqrs/Karabiner-Elements/bin/karabiner_cli' --select-profile 'Default'"
}

Or:

{
  "editorFocusNotifier.onEnterEditorCommand": "'/Library/Application Support/org.pqrs/Karabiner-Elements/bin/karabiner_cli' --set-variable '{"vscode_editor_focused": true}'",
  "editorFocusNotifier.onLeaveEditorCommand": "'/Library/Application Support/org.pqrs/Karabiner-Elements/bin/karabiner_cli' --set-variable '{"vscode_editor_focused": false}'"
}

Example Configuration With BetterTouchTool

{
  "editorFocusNotifier.onEnterEditorCommand": "open 'btt://set_number_variable?variableName=VSCodeEditorFocused&value=1'",
  "editorFocusNotifier.onLeaveEditorCommand": "open 'btt://set_number_variable?variableName=VSCodeEditorFocused&value=0'"
}

Commands

• Editor Focus Notifier: Show Current State - Display the current focus state
• Editor Focus Notifier: Force Reevaluate - Manually trigger state reevaluation

How It Works

The extension considers the editor to be focused when:

• VS Code window is focused, AND
• An active text editor exists

In all other cases (terminal focused, sidebar focused, window unfocused, etc.), the state is "non-editor".

Commands are executed only when the state actually changes, preventing unnecessary executions.

Output Channel

Check the "Editor Focus Notifier" output channel for debugging information about state transitions and command execution.

License

MIT

Repository

https://github.com/knu/vscode-editor-focus-notifier