onMoveCursorBackwardByCharacter property Null safety

MoveCursorHandler? onMoveCursorBackwardByCharacter

The handler for SemanticsAction.moveCursorBackwardByCharacter.

This handler is invoked when the user wants to move the cursor in a text field backward by one character.

TalkBack users can trigger this by pressing the volume down key while the input focus is in a text field.

Implementation

MoveCursorHandler? get onMoveCursorBackwardByCharacter => _onMoveCursorBackwardByCharacter;
void onMoveCursorBackwardByCharacter=(MoveCursorHandler? handler)

Implementation

set onMoveCursorBackwardByCharacter(MoveCursorHandler? handler) {
  if (_onMoveCursorBackwardByCharacter == handler)
    return;
  final bool hadValue = _onMoveCursorBackwardByCharacter != null;
  _onMoveCursorBackwardByCharacter = handler;
  if ((handler != null) != hadValue)
    markNeedsSemanticsUpdate();
}