Text and editing

Text primitives preserve renderer-independent content and coordinates while the native display owns transient selection, shaping, and interaction mechanics. For revisioned editable surfaces, see Editable text surfaces. Implementation details remain in Editable text internals.

Rich selectable text

rich_text/1 renders consumer-produced text and shaping runs without moving Markdown, HTML, syntax, or product policy into the native display. Elixir owns parsing and supplies plain UTF-8 text plus sorted, non-overlapping GPUI.Text.RichRun values:

alias GPUI.Text.{Position, Range, RichRun}

runs = [
  RichRun.new(
    Range.new(Position.new(0, 0), Position.new(0, 7)),
    font_weight: :bold,
    color: 0xF8FAFC
  ),
  RichRun.new(
    Range.new(Position.new(1, 0), Position.new(1, 12)),
    color: 0x60A5FA,
    underline: 0x60A5FA,
    link: "message://details"
  )
]

<UI.rich_text
  id="message-body"
  label="Message"
  text={assigns.text}
  runs={runs}
  phx-link="open_link"
  class="text-slate-300 leading-6"
/>

Run positions use zero-based {line, utf16_offset} coordinates and are converted to native UTF-8 shaping ranges without splitting surrogate pairs. Runs can set foreground/background color, font weight/style, solid or wavy underline, strikethrough, and an opaque bounded link value. Unstyled gaps inherit ordinary component text styles.

Selection is transient native state. Pointer dragging paints selection, the platform select-all and copy shortcuts operate on it, Escape clears it, and a pointer press outside the component discards it. Retained content keeps an unchanged selected byte range across ordinary rerenders and streaming appends; changing the selected bytes or removing the stateful component discards the selection.

A link requires phx-link and emits its opaque value as an ordinary :link event; the framework does not open URLs or interpret schemes. Linked rich text is one native Tab stop. Left/Up and Right/Down navigate links in document order, and Enter or Space uses the same typed event path as pointer activation. AccessKit currently exposes the continuous value as Role::Document with a synthetic Role::TextRun, character lengths, and directional selection facts. Per-link AccessKit actions remain unsupported because pinned GPUI does not provide public action listeners for synthetic child node IDs; the framework does not advertise synthetic clickable links it cannot activate truthfully.

Rich text is bounded to 1 MiB and 2,048 runs and is serialized normally for local, test, and remote displays.