如何在 flutter 中使用设备日历获取事件

Question

I am currently developing a flutter application and would like to display events from the user's device calendar. I have imported the device_calendar API from pub.dev. Here is the code I have so far.

import 'dart:collection';

import 'package:device_calendar/device_calendar.dart';

List<Calendar> calendars;
List<UnmodifiableListView<Event>> calEventsList;

DeviceCalendarPlugin _deviceCalendarPlugin = new DeviceCalendarPlugin();

getUsersCalendar() async{
  try{
    var permissionGranted = await _deviceCalendarPlugin.hasPermissions();
    if(permissionGranted.isSuccess && !permissionGranted.data){

    permissionGranted = await _deviceCalendarPlugin.requestPermissions();

    if(!permissionGranted.isSuccess || !permissionGranted.data){
     return;
   }
  }

 final startDate = DateTime.now().add(Duration(days: -1));
 final endDate = DateTime.now().add(Duration(days: 1));

 final calResult = await _deviceCalendarPlugin.retrieveCalendars();
 calendars = calResult?.data;
 for(int i = 0; i < calendars.length; i++){
  final calEvents = await _deviceCalendarPlugin.retrieveEvents(calendars[i].id, RetrieveEventsParams(startDate: startDate, endDate: endDate));
  calEventsList.add(calEvents.data);
}}
catch(e){
print(e);
}}

After I import this in the main file and do a console print, I get null as the output. Any help would be really appreciated. Thank You in advance.

Answer 1

One tested working calendar is this example code:

https://github.com/builttoroam/device_calendar/blob/master/device_calendar/example/lib/presentation/pages/calendars.dart

I've integrated it copy-and-paste as a app-in-app for a MVP. As far as I remember I also added some uses-permission and then it just worked.

Answer 2

Are you logged into an account... to do so, follow the following instructions

iOS:

1. open the settings app
2. click the button which shows sign in to your iCloud account

android: Sign into account on android