Method to add events from your Android App to default Calendar application

Please pass required parameters to the below method in order add events to default Calendar in android . 

Add Calendar and Accounts permission to manifest. And Also ask for Calendar Runtime permission for 6.0.

 Accounts permission is normal permission so Runtime implementation for same is not required.

 1. Manifest File

<uses-permission android:name="android.permission.GET_ACCOUNTS"/>
<uses-permission android:name="android.permission.READ_CALENDAR"/>
<uses-permission android:name="android.permission.WRITE_CALENDAR"/>
    

2. Methods to add event to Calendar (Modify as per need)

//here you can pass a model class which will contains all your values instead of many parameters


private  void addEventToCalendar(Activity activity,String title,String startDateStr,String startTime,
String endDateStr,String endTime,String eventDescription) {
   
//Getting google accounts linked here 
 Account[] accounts = AccountManager.get(activity).getAccountsByType(
                "com.google");
        String accountName="";
        for (Account acc : accounts) {
            Log.d(">>>>>>>", "Name: " + acc.name + "-----Type: " + acc.type);
            accountName = acc.name;
        }
//Getting required calendar ID here
        long calID = getCalendarId(activity,accountName);
        long startMillis = 0;
        long endMillis = 0;
        Date startDate = null;
//Converting date/time as per need
        try {
            startDate = new SimpleDateFormat("yyyy-MM-dd hh:mmaa", Locale.ENGLISH).parse(startDateStr+" "+startTime);
        } catch (ParseException e1) {
            e1.printStackTrace();
        }
        startMillis = startDate.getTime();
        Date endDate = null;
        try {
            endDate = new SimpleDateFormat("yyyy-MM-dd hh:mmaa", Locale.ENGLISH).parse(endDateStr+" "+endTime);
        } catch (ParseException e) {
            e.printStackTrace();
        }
        endMillis = endDate.getTime();

//Creating  content values which will be used to enter data from a query into calendar content resolver

ContentResolver cr = activity.getContentResolver();
        ContentValues values = new ContentValues();
        values.put(CalendarContract.Events.DTSTART, startMillis);
        values.put(CalendarContract.Events.DTEND, endMillis);
        values.put(CalendarContract.Events.TITLE, title);
        values.put(CalendarContract.Events.DESCRIPTION,eventDescription);
        values.put(CalendarContract.Events.CALENDAR_ID, calID);
        values.put(CalendarContract.Events.EVENT_TIMEZONE, Calendar.getInstance().getTimeZone().getDisplayName());
        try
        {
// Executing query to enter event into the calendar here
            Uri uri = cr.insert(CalendarContract.Events.CONTENT_URI, values);
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
    }
 
 
  private static long getCalendarId(Activity activity,String MY_ACCOUNT_NAME) {
        String[] projection = new String[] { BaseColumns._ID };
        String selection = CalendarContract.Calendars.ACCOUNT_NAME + " = ?";
        String[] selArgs = new String[] { MY_ACCOUNT_NAME };
        Cursor cursor = activity.getContentResolver().query(
                CalendarContract.Calendars.CONTENT_URI, projection, selection, selArgs, null);
        if (cursor.moveToFirst()) {
            return cursor.getLong(0);
        }
        return -1;
    }

References : http://developer.android.com/index.html