v0.18.0

Added

Core

• ModalPlacement and ModalRequest::placement. An in-tree modal can be
  anchored by its top edge (ModalPlacement::Top { offset }) instead of
  centred, for a surface whose height changes while it is open. Backed by the
  new OverlayPlacement::TopCenter. OverlayPlacement::is_modal says which
  placements the tree treats as modal: Centered and TopCenter.
• EventContext::send_intent_from_focus. Sends an intent from whichever
  widget holds focus once the handler's other effects have been applied, a
  modal dismissal included, the way a keyboard shortcut is sent. A surface
  that closes and then runs a command reaches the actions registered around
  what the user was working in.

Changed

Core

• ModalRequest has a placement field. Code building a ModalRequest
  with a struct literal must add placement: ModalPlacement::Centered; the
  constructors set it.

Widgets

• A text field selects all of its text only when focus arrives by Tab.
  TextInputField, and TextInput, SearchField, PasswordField and
  SpinBox built on it, used to select all on any focus that was not a
  click: a dialog opening, a modal or popover closing, an application's
  request_focus, a screen reader's focus. Those now leave the text and
  the caret as they were. A focus the tree restores after a rebuild puts
  the caret at the end. InputDialog selects its default text when it
  opens; an application that wants the text selected on a focus of its own
  calls TextFieldHandle::select_all.
• CommandPalette has a new look. It opens near the top of the window
  and is as tall as its list, up to ten rows. Each row is one line,
  Category: Name, with the letters the query matched in bold, the
  command's description after it, and the shortcut drawn as a key. Rows grow
  with the global text scale. The arrow keys wrap
  at either end; Home and End move the search field's caret.
• A presented CommandPalette lists cut, copy, paste, undo, redo, select
  all and the editors' own commands, and runs them in the editor it was
  opened over. An embedded palette still leaves them out.
• New message command-palette-category in every widget locale, the
  category prefix of a palette row (File:).

Fixed

Core

• A rebuild that destroyed the focused widget put focus on the first
  focusable widget of the rebuilt subtree, whichever one the user was in,
  so typing after a form rebuilt went on in its first field. Focus now
  comes back to the widget at the same position.

Widgets

• Closing a dialog, popover or menu over a text field selected the
  field's text, so the next key replaced it.

• A CommandPalette with no match rebuilt itself every frame for as long
  as nothing matched, and drew its "No matching command" text outside the
  panel.

• Clicking a palette row ran nothing. It now runs the command.

• Typing in the palette moved the caret to the end after every key, and
  each key or arrow press also lost an input method's composition. The
  search field is no longer rebuilt as the query changes.

• A palette command reached only window-global actions. It now reaches
  an action registered on, or around, the widget the palette was opened
  over.

• The palette's keyboard scrolling assumed seven visible rows, and left
  the highlight out of view at other densities, at other text scales and
  after a scroll with the wheel.

• The highlighted palette row had no outline, so the highlight was
  colour only.

• A presented palette given its own on_dismiss stayed open after
  running a command. It now closes, and the hook still runs once.

Full Changelog: v0.17.2...v0.18.0