Spike: Investigate Q25 Messages key handling for Enter, Alt+Enter, and Alt+Space

[smh786]

Summary

Investigate how physical keyboard events are currently handled in the Q25 Messages app when using the default keyboard setup.

Currently:

• Enter/Return inserts a new line in the message composer.
• Left Alt + Enter/Return changes the input language when a second language is configured.
• Long-pressing the spacebar also allows language switching.

We want to understand whether this behaviour comes from Gboard, Harpocrat, Android keylayout/keychar mapping, the Messages app, or the existing Q25 input helper/accessibility app.

The outcome of this spike should determine whether the input helper app can reliably implement “Send on Enter” behaviour, or whether changes are needed at the keyboard/IME/keylayout layer.

Goals

• Confirm which component currently handles:

  • Enter/Return
  • Left Alt + Enter/Return
  • Left Alt + Space
  • long-press Space

• Confirm whether the Q25 input helper/accessibility app can observe and override these key combinations before they are consumed by the keyboard/IME.

• Confirm whether the Messages app exposes a reliable send button/action that can be triggered by the helper.

• Confirm how to detect that the user is inside an active message chat composer rather than the conversation list or another screen.

Investigation tasks

• Add or enable temporary debug logging in the Q25 input helper for physical keyboard events.

• Log keycode, scan code, modifier state, focused package, focused class, focused text field, and accessibility node info where available.

• Test inside the Messages app with:

  • Enter/Return
  • Left Alt + Enter/Return
  • Left Alt + Space
  • long-press Space

• Test with one language configured and with two languages configured.

• Identify whether Left Alt + Enter/Return reaches the helper app.

• Identify whether the helper can suppress or override Left Alt + Enter/Return.

• Identify whether the send button is discoverable via accessibility node text, content description, view ID, or another stable selector.

• Document whether the fix should be implemented in:

  • the Q25 input helper/accessibility app,
  • Harpocrat/default keyboard,
  • Android keylayout/keychar files,
  • or a combination of these.

Acceptance criteria

• We have logs showing what key events are received by the helper for Enter, Left Alt + Enter, and Left Alt + Space.
• We know whether Left Alt + Enter is consumed by the IME before the helper can act on it.
• We know whether the Messages send button can be reliably found and triggered through accessibility.
• We know how to detect an active Messages chat composer screen.
• A short implementation recommendation is added to the issue or PR notes.
• No permanent behaviour changes are introduced as part of this spike unless they are behind debug-only code or removed before merge.