rrule_picker 0.1.2

RRULE picker is a widget used to manipulate RRULEs in accordance to a subset of RFC 5545.

RRULE Picker

RRULE picker is a widget used to manipulate RRULEs in accordance to a subset of RFC 5545.

Features

• No external dependencies except for intl.

• Supports the following types or recurrence rules:

  • Daily, for example RRULE:FREQ=DAILY;INTERVAL=1.
  • Weekly, by selected days of each nth week, for example RRULE:FREQ=WEEKLY;INTERVAL=2;BYDAY=MO,TH,SU.
  • Monthly, by nth day of each nth month, for example RRULE:FREQ=MONTHLY;INTERVAL=3;BYMONTHDAY=4.
  • Monthly, by weekday of nth week of nth month, for example RRULE:FREQ=MONTHLY;INTERVAL=5;BYDAY=FR;BYSETPOS=-1.
  • Yearly, by nth day of nth month, for example RRULE:FREQ=YEARLY;BYMONTH=7;BYMONTHDAY=8.
  • Yearly, by weekday of nth week of nth month, for example RRULE:FREQ=YEARLY;BYMONTH=9;BYDAY=WE;BYSETPOS=4.

• Allows picking multiple excluded dates, for example EXDATE;VALUE=DATE:20561112,20591101,20840330,20870510.

• Translated to 36 languages.

• Uses flutter_localizations and intl for fluent translations.

Getting started

dart pub add rrule_picker

Usage

import 'package:flutter/material.dart';
import 'package:flutter_localizations/flutter_localizations.dart';
import 'package:rrule_picker/rrule_picker.dart';

void main() => runApp(const RRulePickerExampleApp());

class RRulePickerExampleApp extends StatelessWidget {
  const RRulePickerExampleApp({super.key});

  @override
  Widget build(BuildContext context) => MaterialApp(
    localizationsDelegates: [
      // YourAppLocalizations.delegate,
      RRulePickerLocalizations.delegate,
      GlobalMaterialLocalizations.delegate,
      GlobalCupertinoLocalizations.delegate,
      GlobalWidgetsLocalizations.delegate,
    ],
    supportedLocales: RRulePickerLocalizations.supportedLocales,  // YourAppLocalizations.supportedLocales,
    home: Scaffold(body:
      // YourAppWidget(child:
      RRulePicker(onRRuleChanged: (rrule) => print(rrule))),
      // );
  );
}

More elaborate example can be found in the demo web app's source code.

You can also check the interactive demo web app.

Additional information

• This package is still in development; compatibility may be broken from time to time.
• IMPORTANT: The parser uses regular expressions and does not sanitize the data before processing. It is your responsibility to make sure that the RRULEs are safe before passing them to RRulePicker or RRulePickerController.
• The RRULE parser does not care about entry ordering and is case-insensitive but otherwise is strict when parsing values.
• When parsing fails, the parser falls back to defaults of each FREQ.
• The widget always returns RRULE entries in upper-case whenever it's recommended by the RFC and sticks to RFC-recommended ordering of the entries.

Translations

Currently, most translations are machine-generated, followed by a human review based on intuition rather than language proficiency.

The following example shows how to customize localizations for a specific language:

import 'package:flutter/material.dart';
import 'package:rrule_picker/l10n/l10n_en.dart';

// Extend the generated English localization class
class CustomRRulePickerLocalizationsEn extends RRulePickerLocalizationsEn {
  @override
  String get rrulePickerDayOfMonth => 'Custom Day of Month Translation';
}

// Create a custom delegate that falls back to the default delegate
class CustomRRulePickerDelegate
    extends LocalizationsDelegate<RRulePickerLocalizations> {
  const CustomRRulePickerDelegate();

  @override
  bool isSupported(Locale locale) =>
      RRulePickerLocalizations.delegate.isSupported(locale);

  @override
  Future<RRulePickerLocalizations> load(Locale locale) async =>
      switch (locale.languageCode) {
        'en' => CustomRRulePickerLocalizationsEn(),
        _ => RRulePickerLocalizations.delegate.load(locale),
      };

  @override
  bool shouldReload(
      covariant LocalizationsDelegate<RRulePickerLocalizations> old,
      ) => false;
}

// Use it in your app
void main() {
  runApp(MaterialApp(
    localizationsDelegates: const [
      YourAppLocalizations.delegate,
      // Use your custom delegate INSTEAD of RRulePickerLocalizations.delegate
      CustomRRulePickerDelegate(),
      // ... flutter default delegates (GlobalMaterialLocalizations.delegate, etc.)
    ],
    supportedLocales: YourAppLocalizations.supportedLocales,
    home: const Scaffold(/*...*/),
  ));
}

You can also introduce complete translations for a missing language this way, but it would be much better (and very welcome) to contribute your translations to the project on Weblate.