toPlainText method
Generates a plain text string by concatenating the text of all EasyText elements in the list.
This method is called lazily when the text getter is accessed and
the cache is null.
Returns an empty string if the list contains no elements.
Implementation
String toPlainText() {
if (isEmpty) return '';
return map<String>(
(EasyText n) => '${n.text}',
).join();
}