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A scheduled toast is created using Windows.UI.Notifications.ScheduledToast-Notification
instead of the usual ToastNotification as we’ve been using. There are two forms of scheduled
notification, as indicated by its pair of constructors:
• ScheduledToastNotification(content, deliveryTime) Creates a one-time scheduled toast
with the toast’s XmlDocument in content and the UTC DateTime when it should appear in
deliveryTime.
• ScheduledToastNotification(content, deliveryTime, snoozeInterval, maximumSnoozeCount)
Creates a recurring scheduled toast whose content will appear at deliveryTime. If the toast is
dismissed either explicitly or by letting it disappear on its own, it will continue to appear a total
of maximumSnoozeCount times at intervals defined by the number of milliseconds in
snoozeInterval. The snoozeInterval must be set between 60 seconds and 60 minutes; for
longer intervals it’s best to just schedule separate toasts altogether.
A ScheduledToastNotification also has an id property, a maximum 16-character string that’s used
to identify that toast. If you schedule a toast with the same id as an existing one, the new one will
replace the old.
In all cases, the toast is scheduled by calling the ToastUpdater.addToSchedule method passing in the
notification object. Here’s the process in code, as found Scenario 1 of the Scheduled notifications
sample (js/scenario1.js), where toastDOM is the XmlDocument containing the content and dueTime is
determined by a UI control in the sample. First, for a one-time notification:
var Notifications = Windows.UI.Notifications;
toast = new Notifications.ScheduledToastNotification(toastDOM, dueTime);
Notifications.ToastNotificationManager.createToastNotifier().addToSchedule(toast);
Second, for a notification that will repeat five times at 60-second intervals (the option that’s exercised
if you check the Repeat checkbox in the sample’s UI):
var Notifications = Windows.UI.Notifications;
toast = new Notifications.ScheduledToastNotification(toastDOM, dueTime, 60 * 1000, 5);
Notifications.ToastNotificationManager.createToastNotifier().addToSchedule(toast);
To enumerate currently scheduled toasts, call ToastNotifier.getScheduledToast-Notifications.
This returns a vector of ScheduledToastNotification objects, any of which can be canceled through
ToastNotifier.removeFromSchedule. These methods are demonstrated in Scenario 2 of the Scheduled
notifications sample that I will leave you to examine more closely. Also, there are some debugging tips
on the Guidelines and checklist for scheduled notifications topic in the documentation, mostly to note
that the system has a limit of 4096 total notifications and to make sure you’ve set Toast Capable in the
manifest to Yes.
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