# Development Guidelines ## When to Use You can set your application to call the **ReminderRequest** class to create scheduled reminders for countdown timers, calendar events, and alarm clocks. When the created reminders are published, the timing and pop-up notification functions of your application will be taken over by the reminder agent in the background, even when your application is frozen or exits. ## Available APIs **reminderAgent** encapsulates the methods for publishing and canceling reminders. **Table 1** Major APIs in reminderAgent

API	Description
function publishReminder(reminderReq: ReminderRequest, callback: AsyncCallback<number>): void; function publishReminder(reminderReq: ReminderRequest): Promise<number>;	Publishes a scheduled reminder. The maximum number of valid notifications (excluding expired ones that will not pop up again) is 30 for one application and 2000 for the entire system.
function cancelReminder(reminderId: number, callback: AsyncCallback<void>): void; function cancelReminder(reminderId: number): Promise<void>;	Cancels a specified reminder. (The value of reminderId is obtained from the return value of publishReminder.)
function getValidReminders(callback: AsyncCallback<Array<ReminderRequest>>): void; function getValidReminders(): Promise<Array<ReminderRequest>>;	Obtains all valid reminders set by the current application.
function cancelAllReminders(callback: AsyncCallback<void>): void; function cancelAllReminders(): Promise<void>;	Cancels all reminders set by the current application.
function addNotificationSlot(slot: NotificationSlot, callback: AsyncCallback<void>): void; function addNotificationSlot(slot: NotificationSlot): Promise<void>;	Registers a NotificationSlot instance to be used by the reminder.
function removeNotificationSlot(slotType: notification.SlotType, callback: AsyncCallback<void>): void; function removeNotificationSlot(slotType: notification.SlotType): Promise<void>;	Removes a NotificationSlot instance of a specified type.

**ActionButtonType** enumerates types of buttons displayed in a reminder notification. **Table 2** ActionButtonType enumeration

Name	Description
ACTION_BUTTON_TYPE_CLOSE	Close button, which can be tapped to stop the reminder alert tone, close the reminder notification, and cancel the reminder snoozing.

**ReminderType** enumerates the reminder types. **Table 3** ReminderType enumeration

Name	Description
REMINDER_TYPE_TIMER	Countdown reminder.
REMINDER_TYPE_CALENDAR	Calendar reminder.
REMINDER_TYPE_ALARM	Alarm reminder.

**ActionButton** defines a button displayed in the reminder notification. **Table 4** ActionButton instance

Name	Type	Mandatory	Description
title	string	Yes	Text on the button.
type	ActionButtonType	Yes	Button type.

**WantAgent** sets the package and ability that are redirected to when the reminder notification is clicked. **Table 5** WantAgent instance

Name	Type	Mandatory	Description
pkgName	string	Yes	Name of the package redirected to when the reminder notification is clicked.
abilityName	string	Yes	Name of the ability redirected to when the reminder notification is clicked.

**MaxScreenWantAgent** sets the name of the target package and ability to start automatically when the reminder arrives and the device is not in use. If the device is in use, a notification will be displayed. **Table 6** MaxScreenWantAgent instance

Name	Type	Mandatory	Description
pkgName	string	Yes	Name of the package that is automatically started when the reminder arrives and the device is not in use.
abilityName	string	Yes	Name of the ability that is automatically started when the reminder arrives and the device is not in use.

**ReminderRequest** defines the reminder to publish. **Table 7** ReminderRequest instance

Name	Type	Mandatory	Description
reminderType	ReminderType	Yes	Type of the reminder.
actionButton	[ActionButton?, ActionButton?]	No	Action button displayed in the reminder notification.
wantAgent	WantAgent	No	Information about the ability that is redirected to when the notification is clicked.
maxScreenWantAgent	MaxScreenWantAgent	No	Information about the ability that is automatically started when the reminder arrives. If the device is in use, a notification will be displayed.
ringDuration	number	No	Ring duration.
snoozeTimes	number	No	Number of reminder snooze times.
timeInterval	number	No	Reminder snooze interval.
title	string	No	Reminder title.
content	string	No	Reminder content.
expiredContent	string	No	Extended content to be displayed when the reminder expires.
snoozeContent	string	No	Extended content to be displayed when the reminder is snoozing.
notificationId	number	No	Notification ID used by the reminder. For details, see the API reference of the NotificationRequest.setNotificationId(int id) method.
slotType	SlotType	No	Type of the slot used by the reminder

**ReminderRequestCalendar** extends **ReminderRequest** and defines a reminder for a calendar event. The earliest reminder time must be later than the current time. **Table 8** ReminderRequestCalendar instance

Name	Type	Mandatory	Description
dateTime	LocalDateTime	Yes	Reminder time.
repeatMonths	Array<number>	No	Months in which the reminder repeats.
repeatDays	Array<number>	No	Date on which the reminder repeats.

**ReminderRequestAlarm** extends **ReminderRequest** and defines a reminder for the alarm clock. **Table 9** ReminderRequestAlarm instance

Name	Type	Mandatory	Description
hour	number	Yes	Hour portion of the reminder time.
minute	number	Yes	Minute portion of the reminder time.
daysOfWeek	Array<number>	No	Days of a week when the reminder repeats.

**ReminderRequestTimer** extends **ReminderRequest** and defines a reminder for a scheduled timer. **Table 10** ReminderRequestTimer instance

Name	Type	Mandatory	Description
triggerTimeInSeconds	number	Yes	Number of seconds in the countdown timer.

**LocalDateTime** defines a **LocalDateTime** instance. **Table 11** LocalDateTime instance

Name	Type	Mandatory	Description
year	number	Yes	Year.
month	number	Yes	Month.
day	number	Yes	Date.
hour	number	Yes	Hour.
minute	number	Yes	Minute.
second	number	No	Second.

## How to Develop >![](../public_sys-resources/icon-note.gif) **NOTE:** >To publish a reminder, your application needs to apply for the **ohos.permission.PUBLISH\_AGENT\_REMINDER** permission. Publish a 10-second countdown reminder. 1. Define a countdown timer instance. ``` import reminderAgent from '@ohos.reminderAgent'; import notification from '@ohos.notification'; export default { timer: { reminderType: reminderAgent.ReminderType.REMINDER_TYPE_TIMER, triggerTimeInSeconds: 10, actionButton: [ { title: "close", type: reminderAgent.ActionButtonType.ACTION_BUTTON_TYPE_CLOSE } ], wantAgent: { pkgName: "com.huawei.phone", abilityName: "com.huawei.phone.MainAbility" }, maxScreenWantAgent: { pkgName: "com.huawei.phone", abilityName: "com.huawei.phone.MainAbility" }, title: "this is title", content: "this is content", expiredContent: "this reminder has expired", notificationId: 100, slotType: notification.SlotType.SOCIAL_COMMUNICATION } } ``` 2. Publish the reminder. ``` startTimer() { reminderAgent.publishReminder(this.timer, (err, reminderId) =>{ this.printInfo(JSON.stringify(err)); this.printInfo("reminderId:" + reminderId); }); } ``` HTML page code: ```

``` Sample code for defining a calendar reminder instance: ``` calendar: { reminderType: reminderAgent.ReminderType.REMINDER_TYPE_CALENDAR, dateTime: { year: 2050, month: 7, day: 30, hour: 11, minute: 14, second: 30 }, repeatMonths: [0], repeatDays: [0], actionButton: [ { title: "close", type: reminderAgent.ActionButtonType.ACTION_BUTTON_TYPE_CLOSE }, { title: "snooze", type: reminderAgent.ActionButtonType.ACTION_BUTTON_TYPE_SNOOZE }, ], wantAgent: { pkgName: "com.huawei.phone", abilityName: "com.huawei.phone.MainAbility" }, maxScreenWantAgent: { pkgName: "com.huawei.phone", abilityName: "com.huawei.phone.MainAbility" }, ringDuration: 5, snoozeTimes: 2, timeInterval: 5, title: "this is title", content: "this is content", expiredContent: "this reminder has expired", snoozeContent: "remind later", notificationId: 100, slotType: notification.SlotType.SOCIAL_COMMUNICATION } ``` Sample code for defining an alarm reminder instance: ``` alarm: { reminderType: reminderAgent.ReminderType.REMINDER_TYPE_ALARM, hour: 11, minute: 14, daysOfWeek: [0], actionButton: [ { title: "close", type: reminderAgent.ActionButtonType.ACTION_BUTTON_TYPE_CLOSE }, { title: "snooze", type: reminderAgent.ActionButtonType.ACTION_BUTTON_TYPE_SNOOZE }, ], wantAgent: { pkgName: "com.huawei.phone", abilityName: "com.huawei.phone.MainAbility" }, maxScreenWantAgent: { pkgName: "com.huawei.phone", abilityName: "com.huawei.phone.MainAbility" }, ringDuration: 5, snoozeTimes: 2, timeInterval: 5, title: "this is title", content: "this is content", expiredContent: "this reminder has expired", snoozeContent: "remind later", notificationId: 100, slotType: notification.SlotType.SOCIAL_COMMUNICATION } ```