dispatchDiagramKeyBinding function

bool dispatchDiagramKeyBinding(DiagramController session, Iterable<DiagramKeyBinding> bindings, KeyEvent event, { String? elementId, String? slotId, bool editing = false, })

Implementation

bool dispatchDiagramKeyBinding(
  DiagramController session,
  Iterable<DiagramKeyBinding> bindings,
  KeyEvent event, {
  String? elementId,
  String? slotId,
  bool editing = false,
}) {
  if (event is! KeyDownEvent || event.logicalKey == LogicalKeyboardKey.escape) {
    return false;
  }
  final keyboard = HardwareKeyboard.instance;
  final command = defaultTargetPlatform == TargetPlatform.macOS
      ? keyboard.isMetaPressed
      : keyboard.isControlPressed;
  // Reject the other command modifier, so chords remain exact.
  if (defaultTargetPlatform == TargetPlatform.macOS
      ? keyboard.isControlPressed
      : keyboard.isMetaPressed) {
    return false;
  }
  final scope = editing
      ? DiagramKeyScope.text
      : session.selection is EmptySelection
      ? DiagramKeyScope.canvas
      : DiagramKeyScope.selection;
  elementId ??= switch (session.selection) {
    ElementSelection(:final elementIds) when elementIds.length == 1 =>
      elementIds.single,
    StorySelection(:final elementId) => elementId,
    ConnectorLabelSelection(:final connectorId) => connectorId,
    _ => null,
  };
  final type = switch (session.document.elementById(elementId ?? '')) {
    ShapeElement(:final type) => type,
    _ => null,
  };
  final textType = editing
      ? session.diagram.resolver.registry
            .textFor(
              session.document.elementById(elementId ?? ''),
              slotId: slotId,
            )
            .type
      : null;
  final pressed = {
    if (command) DiagramKeyModifier.command,
    if (keyboard.isAltPressed) DiagramKeyModifier.alt,
    if (keyboard.isShiftPressed) DiagramKeyModifier.shift,
  };
  final candidates =
      bindings
          .where(
            (b) =>
                b.key == event.logicalKey &&
                b.scope == scope &&
                setEquals(b.modifiers, pressed) &&
                (b.shapeType == null || b.shapeType == type) &&
                (b.textType == null || b.textType == textType) &&
                (b.slotId == null || b.slotId == slotId),
          )
          .toList()
        ..sort((a, b) => b._specificity.compareTo(a._specificity));
  if (candidates.isEmpty) return false;
  final binding = candidates.first;
  session.edits.perform(
    [?elementId],
    binding.verb,
    binding.args?.call(session, elementId) ?? const {},
  );
  // A matched binding owns its chord even when its verb is unavailable.
  return true;
}