SharePoint Calendar Rollup is designed to substantially expand and enhance the functionality of the default Microsoft SharePoint calendar by a wide range of features and capabilities.
1. Adding a Calendar
On top right of SharePoint Calendar Rollup Web Part, there’s a dropdown menu, select Add Calendar

Choose which calendar (SharePoint List, Exchange Calendar, Google Calendar and External Content Type) you would like to import to your SharePoint Calendar Rollup web part.
1.1. Calendar Settings
Type the title of the calendar;
Enabled - displays the data on SharePoint Calendar Web Part.
Read Only - does not let SharePoint users edit data.
To make your calendar easy to differentiate, color-code your calendar by ticking the Custom color.

1.2. Data source configuration
There are four different sources, namely, SharePoint List or Library, Exchange Calendar, Google Calendar and External Content Type and each has its own settings.
a. SharePoint List or Library

b. Exchange Calendar

c. Google Account

d. External content type

1.3. Tooltip Settings
Choose columns to be displayed on calendar when an item is clicked.

2. Calendar Rollup General Settings
On this page, you will see information about your Calendar Rollup Web Part, General Settings and calendars that are included in the rollup. You may also add a new calendar by clicking the link on the lower left of the list.

2.1 Basic Settings

Default View – set to show the default view on your Calendar Rollup web part – by month, week or day.
Show calendar filter – enabling this lets users view and filter what calendars would be displayed on the rollup.

Show print – next to the calendar filter is the print button, activate this if you wish to show the print button on the Calendar Rollup web part.
Show tooltip for event bar – when activated, hovering the mouse over an event shows a summarized detail of the event.

2.2. Permission Settings
You could set other users to edit your calendar. Selecting SharePoint Default check box will maintain the same permission settings with SharePoint, while the another check box allows you to set particular users or groups to edit your calendar.

3. Navigating your Calendar
There are several options and features in your Rollup Calendar front page.
a. To access the web part settings, hover over to the top corner right of the web part and click the arrow button.

Edit Web Part – lets you personalize how your Calendar Rollup would look.

b. There are several buttons on the top right corner of the web part.

Expand/Collapse Calendar Events – clicking between these buttons shows or hides all the events in the calendar.

You may also click the text below the list to expand or collapse a specific date.

You may also click the text below the list to expand or collapse a specific date.
Toggle between Day, Week or Month view.
Calendars – filter to view different calendars available
Print – print the calendar
Refresh – refresh the page to update calendar
Note: The last three buttons can be shown or hid in your web part, go to Basic Settings for this option.
c. We make it easier for users to drag and drop calendar events as well as drag the event to change the time. Also, drag to cover the days without creating another event.
Note: Moving an event to different dates only works with Month and Week view.

The two square white tabs indicate that the event is available for dragging.

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