1# Flip Clock 2 3### Introduction 4 5 This sample uses the Feature Ability (FA) model and related APIs to implement a simple flip clock app. Below shows the sample app. 6 7  8 9### Concepts 10 11**reminderAgent**: a class that provides APIs 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 when your application is frozen or exits. 12 13### Required Permissions 14 15ohos.permission.PUBLISH_AGENT_REMINDER (permission for the reminder agent) 16 17ohos.permission.RUNNING_LOCK (permission for the running lock) 18 19### Usage 20 211. There are four tab bars (**Clock**, **Alarm**, **Countdown**, and **Settings**) at the bottom of the home page of the sample app. The **Clock** tab page displays a flip clock. 22 232. On the **Alarm** tab page, you can touch **+** to create an alarm record. When the alarm time arrives, a notification will be displayed. 24 253. The **Countdown** tab page provides the countdown function. 26 274. The **Settings** tab page provides the following functions: full screen, screen brightness adjustment, and screen-on. 28 29### Constraints 30 311. This sample can only be run on standard-system devices. 32 332. This sample requires DevEco Studio 3.0 Beta4 (Build Version: 3.0.0.992, built on July 14, 2022) to compile and run. 34
