putBoolean method
Add a boolean attribute for the given key.
The attribute key should be a string composed of letters, numbers or underscores ([a-z0-9_]) and can't be longer than 30 characters.
Implementation
BatchEventAttributes putBoolean(String key, bool value) {
_attributes[key.toLowerCase()] = TypedAttribute(type: TypedAttributeType.boolean, value: value);
return this;
}