HarmonyOS开发实例：【任务延时调度】

介绍

本示例使用[@ohos.WorkSchedulerExtensionAbility] 、[@ohos.net.http]、[@ohos.notification] 、[@ohos.bundle]、[@ohos.fileio] 等接口，实现了设置后台任务、下载更新包、保存更新包、发送通知、安装更新包实现升级的功能。

效果预览

使用说明

安装本应用之前，先编译好未签名的应用包，然后在终端执行工程里的脚本，目录为：WorkScheduler/signTool/b_sign_hap_release.bat；
未连接wifi状态下进入应用；
进入首页后连接wifi；
后台判断版本号后会下载新的升级包，并在页面中给出弹窗询问是否安装，点击“确定”按钮；
应用会安装已经下载的升级包，实现版本更新，安装后会回到设备桌面，此时点击应用图标，可以看到版本已经是新版本了。
运行自动化测试用例时，必须使用命令行装包，不能使用ide自动装包，安装自动化测试包之前，先编译好未签名的测试包，然后在终端执行工程里的脚本，目录为：WorkScheduler/signTool/a_sign_hap_release.bat；
运行自动化测试应用时需要使用如下命令：

hdc shell aa test -b ohos.samples.workschedulerextensionability -m entry_test -s unittest OpenHarmonyTestRunner -s class ActsAbilityTest -s timeout 150000

代码解读

entry/src/main/ets/
|---Application
|   |---MyAbilityStage.ets                  // 入口文件
|---feature
|   |---WorkSchedulerSystem.ets             // 封装各个功能接口
|---MainAbility
|   |---MainAbility.ets                     // 请求权限
|---pages
|   |---Index.ets                           // 首页
|---util
|   |---Logger.ets                          // 日志文件
|---WorkSchedulerAbility
|   |---WorkSchedulerAbility.ets            // 延时任务触发后的回调

搜狗高速浏览器截图20240326151547.png

具体实现

鸿蒙next开发知识更新在：gitee.com/li-shizhen-skin/harmony-os/blob/master/README.md

设置延时任务、下载更新包、保存更新包、发送通知、安装更新包的功能接口都封装在WorkSchedulerSystem中，源码参考：[WorkSchedulerSystem.ets]

/** Copyright (c) 2023-2024 Huawei Device Co., Ltd.* Licensed under the Apache License, Version 2.0 (the "License");* you may not use this file except in compliance with the License.* You may obtain a copy of the License at**     http://www.apache.org/licenses/LICENSE-2.0** Unless required by applicable law or agreed to in writing, software* distributed under the License is distributed on an "AS IS" BASIS,* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.* See the License for the specific language governing permissions and* limitations under the License.*/import fs from '@ohos.file.fs';import notificationManager from '@ohos.notificationManager';import Notification from '@ohos.notification';import bundle from '@ohos.bundle.installer';import account from '@ohos.account.osAccount';import workScheduler from '@ohos.resourceschedule.workScheduler';import http from '@ohos.net.http';import { Logger } from '../utils/Logger';const FILE_NAME = '/UpdateWorkScheduler.hap';const BUNDLE_NAMES = ['ohos.samples.workschedulerextensionability'];const INSTALL_PARAMETER = 1;export namespace WorkSchedulerSystem {/*** Store the file to the specified directory.** @param pathDir Path to save the file.* @param content The contents of the file to be saved.*/export function saveFile(pathDir: string, content: ArrayBuffer): void {try {let filePath = pathDir + FILE_NAME;let fd = fs.openSync(filePath, 0o2 | 0o100).fd;fs.writeSync(fd, content);fs.closeSync(fd);} catch (err) {Logger.error(`saveFile failed, code is ${err.code}, message is ${err.message}`);}}/*** Sending a Notification.** @param bundleName Check the name of the application that has permission.* @permission ohos.permission.NOTIFICATION_CONTROLLER*/export async function handleNotification(bundleName: string): Promise<void> {await notificationManager.requestEnableNotification();Notification.subscribe({onConsume: (data) => {if (data.request.content.normal.text === 'isReady') {AppStorage.SetOrCreate('isShowDialog', true);}}}, {bundleNames: BUNDLE_NAMES})}/*** Publishes a notification of the specified content.** @param title Title of Notice.* @param text Content of Notification Text.* @param additionalText Additional text.* @permission ohos.permission.NOTIFICATION_CONTROLLER*/export function publishNotification(title: string, text: string, additionalText: string): void {notificationManager.publish({content: {contentType: Notification.ContentType.NOTIFICATION_CONTENT_BASIC_TEXT,normal: {title,text,additionalText}}})}/*** Install the application package in the specified path.** @param filePath An array of paths to hold the installation package.* @permission ohos.permission.INSTALL_BUNDLE*/export async function installBundle(filePath: Array<string>): Promise<void> {try {let bundleInstall = await bundle.getBundleInstaller();let userId = await account.getAccountManager().getOsAccountLocalIdFromProcess();bundleInstall.install(filePath, {userId: userId,installFlag: INSTALL_PARAMETER,isKeepData: false}, (status, statusMessage) => {Logger.info(`installBundle filepath is ${filePath}`);Logger.info(`installBundle code is ${status.code}, message is ${JSON.stringify(statusMessage)}`);})} catch (err) {Logger.error(`installBundle failed, code is ${err.code}, message is ${err.message}`);}}/*** Register the delayed task and pass the parameters.** @param version Current application version.* @param bundleName The name of the application package for which the task needs to be registered.* @param filePath Storage address of the application package.*/export async function startUpdateSample(version: string, bundleName: string, filePath: string): Promise<void> {try {let workInfo = {workId: 1,bundleName: bundleName,abilityName: 'WorkSchedulerAbility',networkType: workScheduler.NetworkType.NETWORK_TYPE_WIFI,parameters: {version: version,filePath: filePath}};workScheduler.startWork(workInfo);}catch (err) {Logger.error(`startWork failed, code is ${err.code}, message is ${err.message}`);}}/*** Register the delayed task and pass the parameters.** @param url Url of the application package.* @permission ohos.permission.INTERNET*/export async function getNewHap(url: string): Promise<http.HttpResponse> {try {return await http.createHttp().request(url,{expectDataType: http.HttpDataType.ARRAY_BUFFER});} catch (err) {Logger.error(`get result failed, code is ${err.code}, message is ${err.message}`);}}}

设置延时任务：在运行示例时会在[MainAbility.ets] 通过WorkSchedulerSystem.startUpdateSample()方法调用workScheduler.startWork()建立任务；
下载更新包：当任务条件满足后，会在[WorkSchedulerAbility.ets]通过WorkSchedulerSystem.getNewHap()方法调用http.createHttp().request()接口下载需要的文件；
保存更新包：通过WorkSchedulerSystem.saveFile()来实现，受限调用fileio.openSync()创建文件，然后调用fileio.writeSync()将下载的内容写入指定文件内；
发送通知：在[WorkSchedulerAbility.ets] 中通过WorkSchedulerSystem.publishNotification()方法，调用Notification.publish()接口发送指定内容的信息；
接收通知：在[MainAbility.ets]中通过WorkSchedulerSystem.handleNotification()方法调用Notification.subscribe()接口获取信息，根据信息内容决定是否提示用户升级；
安装更新包：在[WorkSchedulerAbility.ets] 通过WorkSchedulerSystem.installBundle()方法实现，首先调用bundle.getBundleInstaller()获取Installer对象，然后调用bundleInstall.install()接口实现装包，完成升级。

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