ACADOID® Apps — Calendar — Help
See the app page for videos and screenshots.
Terminology
Calendar consists of the following elements
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Layers |
| Layers contain events and tasks; there are active layers (for which events and tasks are shown) and passive layers (for which events and tasks are hidden).
Layers have a name and a color. Click to edit, long-click for options, drag to the left/to the right to activate/deactivate, and drag to the top to discard (only empty or fully synchronized layers can be discarded). |
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Events |
| Events are items which are assigned to a specific period.
Events have a name, a start and end time, they can have a recurrence frequency and a notification;
you can assign locations, attendees, descriptions, and attachments to events. Click to edit, long-click for options, drag up/down to reschedule, and drag to the top to discard. |
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Tasks |
| Tasks are items which are not assigned to a specific period.
Tasks have a name;
you can assign descriptions and attachments to tasks. Click to edit, drag up/down to reorder, and drag to the top to discard. |
Display
Layer icons
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Synchronization (click to change, see below) | |
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Color (click to change) | |
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Number of events and next event (information only) | |
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Next event is a recurrence | |
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Number of tasks (information only) |
Event icons
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Layer (click to change) | |
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Start time, end time, and duration (click to correct) | |
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Time is in the past | |
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Recurrence frequency and duration (click to change) | |
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Time is in the past | |
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Disable recurrence | |
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Enable recurrence | |
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Notifications (click to change, long-click to discard) | |
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Time is in the past | |
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Add notification | |
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Location | |
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Get directions | |
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Attendees (click to send email, long-click to discard) | |
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Add attendee | |
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Description | |
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Attachments (click to view, long-click to discard) | |
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Add attachment |
Task icons
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Layer (click to change) | |
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Description | |
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Attachments | |
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Add attachment |
Usage
Action icons
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Find in calendar |
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Synchronize layers |
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Synchronize layers (last attempt failed) |
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Synchronize layers (disabled) |
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Scroll and zoom to next event |
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Scroll and zoom to today |
Floating action icons
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Add layer |
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Add event |
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Add task |
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Paste event (instead of adding a new empty event) |
Layer option icons
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Scroll and zoom to next event of this layer |
Event option icons
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Move downward |
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Copy event |
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Cut event |
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Disable recurrence |
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Enable recurrence |
Holidays and birthdays
Calendar has the main religious holidays of several denominations and the public holidays of several countries built-in. Additional ‘user-defined holidays’ can be defined in JavaScript. The built-in holidays are defined in JavaScript as well, this JavaScript code can be copied to the field for ‘user-defined holidays’ and modified.
Birthdays can be defined in JavaScript.
The usage of JavaScript allows holidays and birthdays that do not have a fixed date in the Gregorian calendar.
Definitions
Besides the standard JavaScript commands, the following additional ones are available:
| (Number) Calendar.getYear() | returns the year in Gregorian calendar for which holidays need to be determined |
| (Number) Calendar.getWeekday(Number month, Number day) | returns the weekday (Sunday equals 1, Monday equals 2, ..., Saturday equals 7) for month month (1 to 12) and day (1 to 28, 29, 30, or 31, depending on month) |
| (Number) Calendar.getDayOfYear(Number month, Number day) | returns the day of the year for month month (1 to 12) and day (1 to 28, 29, 30, or 31, depending on month) |
| (Number) Calendar.getMonth(Number dayOfYear) | returns the month (January equals 1, ..., December equals 12) for day of year dayOfYear |
| (Number) Calendar.getDay(Number dayOfYear) | returns the day (1 to 28, 29, 30, or 31, depending on month) for day of year dayOfYear |
| (Number) Calendar.addHoliday(Number month, Number day, String name, Boolean flag) | adds a major (flag is true) or minor (flag is false) holiday with name name for month month (1 to 12) and day (1 to 28, 29, 30, or 31, depending on month); command only available for user-defined holidays |
| (Number) Calendar.addBirthday(Number month, Number day, String name) | adds a birthday with name name for month month (1 to 12) and day (1 to 28, 29, 30, or 31, depending on month); command only available for birthdays |
Note that that commenting has to be done using ‘/* comment */’ (commenting by ‘//’ does not work) and that your JavaScript code has to finish within 400 ms
Examples
A first simple example, add a major holiday ‘New year’ on January 1
| Calendar.addHoliday(1, 1, "New year", true); | add a major holiday ‘New year’ on January 1 |
A second more complex example, add a birthday on February 29 for leap years and March 1 for non-leap years
| days = Calendar.getDayOfYear(12, 31); | get the number of the last day of the year |
| if (days == 366) { | leap year? |
| Calendar.addBirthday(2, 29, "Bob"); | add Bob's birthday for leap year |
| } else { | |
| Calendar.addBirthday(3, 1, "Bob"); | add Bob's birthday one day later for non-leap years |
| } |
A third more complex example, add a major holiday ‘Martin Luther King Day’ on third Monday in January
| day = 3 * 7 - 6; | minimal day of month for third occurrence of a weekday |
| weekday = Calendar.getWeekday(1, day); | get weekday for day in January |
| while (weekday != 2) { | while not Monday |
| day++; | next day |
| weekday = Calendar.getWeekday(1, day); | get weekday for day in January |
| } | day is now third Monday in January |
| Calendar.addHoliday(1, day, "Martin Luther King Day", true); | add a major holiday ‘Martin Luther King Day’ on third Monday in January |
A fourth more complex example, add moon phases as minor holidays (download code)
| year = Calendar.getYear(); | get year |
| days = Calendar.getDayOfYear(12, 31); | get number of days in year |
| newMoon = new Date(1970, 0, 7, 20, 35, 0); | known date of new moon |
| for (dayOfYear = 1; dayOfYear <= days; dayOfYear++) { | for all days of this year |
| month = Calendar.getMonth(dayOfYear); | get month of day in year |
| day = Calendar.getDay(dayOfYear); | get day of day in year |
| moon = new Date(year, month - 1, day, 20, 35, 0); | get date for day in year |
| diff = moon.getTime() - newMoon.getTime(); | get difference |
| phase = (diff / 1000) % 2551443; | get moon phase |
| switch (Math.floor(phase / (24 * 3600))) { | get moon phase in range 0 to 29 |
| case 0: | new moon |
| case 1: | |
| Calendar.addHoliday(month, day, "\uD83C\uDF11", false); | add ‘new moon’ symbol |
| dayOfYear += 5; | skip five days |
| break; | |
| case 7: | increasing moon |
| case 8: | |
| Calendar.addHoliday(month, day, "\uD83C\uDF12", false); | add ‘increasing moon’ symbol |
| dayOfYear += 5; | skip five days |
| break; | |
| case 15: | full moon |
| case 16: | |
| Calendar.addHoliday(month, day, "\uD83C\uDF15", false); | add ‘full moon’ symbol |
| dayOfYear += 5; | skip five days |
| break; | |
| case 22: | decreasing moon |
| case 23: | |
| Calendar.addHoliday(month, day, "\uD83C\uDF18", false); | add ‘decreasing moon’ symbol |
| dayOfYear += 5; | skip five days |
| break; | |
| } | |
| } |
Widgets
Calendar provides five different widgets
- a day widget which displays a day's view
- a week widget which displays a week's view
- a month widget which displays a month's view
- an events widget which displays the next events
- a tasks widget which displays the tasks
Synchronization
| device | internet | |||||||||
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| synchronization | synchronization | |||||||||
| by Calendar | by system | |||||||||
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| Calendar | calendar database |
cloud calendar |
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Calendar does not upload your data to any cloud calendar, nor does it download any data to your device. ‘Synchronization’ in the description above means that Calendar writes events and tasks to and reads events and tasks from the calendar database on your device. Being able to do that requires Calendar to have the WRITE_CALENDAR/READ_CALENDAR permission, see next section. Your data still remains on your device after Calendar performed this synchronization.
Whether or not the calendar database on your device is synchronized with a cloud calendar (and how the synchronization is performed) is determined by the system settings of your device.
The calendar database on your device consists of one or several parts, each uniquely identified by a user id (which is usually an email address). A layer of Calendar can either not be synchronized with any part of the calendar database (‘No synchronization’) or be synchronized with exactly one part of the calendar database identified by user id id (‘Synchronization with id’). Conversely, each part of the calendar database on your device can either not be synchronized with any layer of Calendar or can be synchronized with exactly one layer of Calendar. The synchronization property can only be chosen when creating a new layer and remains fixed afterwards until you discard the layer (in which case this part of the calendar database can be synchronized with a new layer).
Permissions
Calendar requests the following permissions
- WRITE_CALENDAR/READ_CALENDAR (colloquially
‘Calendar’) allows Calendar to access the calendar database on
your device (colloquially ‘your calendar’).
This permission is required if you wish to synchronize events and tasks in Calendar with the calendar database on your device, see previous section; if you do not grant this permission on devices running Android 6.0 or later, synchronization will not be possible. If you grant this permission, access to the calendar database occurs only if you synchronize. - READ_CONTACTS (colloquially ‘Contacts’) allows
Calendar to access the contacts database on your device (colloquially
‘your contacts’).
This permission is required on some devices as some contacts apps do not grant temporary read access to the contact's name and email address when you select a contact as an attendee. You can revoke this permission on most devices running Android 6.0 or later; Calendar will inform you if it cannot add an attendee without having this permission. If you grant this permission, read access to the contacts database occurs only if you add a contact as attendee, and only the contact's name and email address are read. - POST_NOTIFICATIONS (colloquially ‘Notifications’)
allows Calendar to post notifications in the notification drawer.
This permission is required on devices running Android 13 or later if you wish notifications for events to be displayed in the notification drawer; if you do not grant this permission on devices running Android 13 or later (or if you disable notifications from Calendar on devices running older Android versions), notifications for events will not be displayed in the notification drawer and hence there will be no accompanying ringtone or vibration. - USE_EXACT_ALARM allows Calendar to schedule notifications
at precise times.
This permission is required on devices running Android 13 or later to receive timely notifications for events. It is a special permission intended for apps such as Calendar that rely on exact alarms for their core functionality, and it cannot be revoked on devices running Android 13 or later. - SCHEDULE_EXACT_ALARM (colloquially ‘Alarms &
reminders’) allows Calendar to schedule notifications at precise
times.
This permission is required on devices running Android 12 if you wish to receive timely notifications for events, even if the device is sleeping; if you do not grant this permission on devices running Android 12, notifications for events may be delayed by 10 minutes or more, and may not be displayed at all if the device is sleeping. This permission was replaced by USE_EXACT_ALARM in Android 13, it is not requested on devices running Android 13 or later. - WRITE_EXTERNAL_STORAGE/READ_EXTERNAL_STORAGE
(colloquially ‘Storage’) allows Calendar to access the file
system.
This permission is required on devices running older Android versions, it is not requested on devices running Android 6.0 or later. - RECEIVE_BOOT_COMPLETED allows Calendar to receive a message
after boot is completed and to reschedule notifications (which get deleted
by a reboot).
This is a minor permission which cannot be revoked on devices running Android 6.0 or later. - WAKE_LOCK allows Calendar to post notifications even if the
device is sleeping.
This is a minor permission which cannot be revoked on devices running Android 6.0 or later. - VIBRATE allows Calendar to use vibration for notifications.
This permission is required on devices running older Android versions. It is a minor permission which cannot be revoked on devices running Android 6.0 or later.