compose method

void compose(Delta change, { TextSelection? selection, ChangeSource source = ChangeSource.remote, })

Composes change into document managed by this controller.

This method does not apply any adjustments or heuristic rules to provided change and it is caller's responsibility to ensure this change can be composed without errors.

If composing this change fails then this method throws ComposeError.

Implementation

void compose(Delta change,
    {TextSelection? selection, ChangeSource source = ChangeSource.remote}) {
  if (change.isNotEmpty) {
    document.compose(change, source);
  }
  if (selection != null) {
    _updateSelectionSilent(selection, source: source);
  } else {
    // Transform selection against the composed change and give priority to
    // current position (force: false).
    final base =
        change.transformPosition(_selection.baseOffset, force: false);
    final extent =
        change.transformPosition(_selection.extentOffset, force: false);
    selection = _selection.copyWith(baseOffset: base, extentOffset: extent);
    if (_selection != selection) {
      _updateSelectionSilent(selection, source: source);
    }
  }
  notifyListeners();
}