clearSelection method
Clears the range of text.
Notice that JidoujishoSelectableText.onSelectionChanged won't be called.
Implementation
void clearSelection() {
if (_textSpanEditingController == null) {
return;
}
_textSpanEditingController!.value =
_textSpanEditingController!.value.copyWith(
selection: const TextSelection.collapsed(offset: -1),
);
}