clear method

void clear ()

Set the value to empty.

After calling this function, text will be the empty string and the selection will be invalid.

Calling this will notify all the listeners of this TextEditingController that they need to update (it calls notifyListeners). For this reason, this method should only be called between frames, e.g. in response to user actions, not during the build, layout, or paint phases.

Implementation 

void clear() {
  value = TextEditingValue.empty;
}