环信鸿蒙IM SDK实现附件消息发送与下载

环信HarmonyOS IM SDK 正式版已经发布，该版本全面覆盖即时通讯（IM）的核心功能，为用户提供了完整的IM全功能体验，同时支持从Android APK到 NEXT 的数据迁移，更好地满足企业在不同业务场景下的适配需求。

点此下载最新版环信 HarmonyOS IM SDK

环信鸿蒙IM SDK 除文本消息外，还支持发送附件类型消息，包括语音、图片、视频和文件消息。本文为大家介绍从系统获取系统图片，视频，语音文件，使用sdk进行发送与下载。

一、发送附件消息

1、发送图片消息

① 权限添加
在对应模块的module.json5配置中，添加requestPermissions节点和对应权限的配置：

{"name": "ohos.permission.READ_MEDIA","reason": "$string:app_name","usedScene": {"abilities": ["EntryAbility"]}
},
{"name": "ohos.permission.WRITE_MEDIA","reason": "$string:app_name","usedScene": {"abilities": ["EntryAbility"]}
}

② 权限检测

//检查权限
export  async function checkAppPermission(context:common.UIAbilityContext): Promise<boolean> {try {const READ_MEDIA_PERMISSION: Permissions = 'ohos.permission.READ_MEDIA' //媒体读取权限const WRITE_MEDIA_PERMISSION: Permissions = 'ohos.permission.WRITE_MEDIA' //媒体写入权限let permissionList: Permissions[] = []; //需要申请选项列表let readPermission = await checkPermissions(READ_MEDIA_PERMISSION)//检查是否有媒体读取权限!readPermission && permissionList.push(READ_MEDIA_PERMISSION)let writePermission = await checkPermissions(WRITE_MEDIA_PERMISSION)//检查是否有媒体写入权限!writePermission && permissionList.push(READ_MEDIA_PERMISSION)if (permissionList.length) {//申请权限let res: boolean = await applyPermission(context, permissionList)if (!res) {//用户未同意授权AlertDialog.show({title: "提示",message: "无权限读写用户外部存储中的媒体文件信息，请前往系统设置开启",alignment: DialogAlignment.Center,secondaryButton: {value: '关闭',action: () => {}}})
}
return res
}
return true}catch (e) {return Promise.reject(e)
}
}

检查用户权限：

//检查用户权限
//@params permissions:权限名称数组
export  async function checkPermissions(permissions: Permissions): Promise<boolean> {try {let grantStatus: abilityAccessCtrl.GrantStatus = await checkAccessToken(permissions);return grantStatus === abilityAccessCtrl.GrantStatus.PERMISSION_GRANTED}catch (e) {return Promise.reject(e)}
}

从相册中选择图片：

 //从相册选择let PhotoSelectOptions = new picker.PhotoSelectOptions();PhotoSelectOptions.MIMEType = picker.PhotoViewMIMETypes.IMAGE_TYPE;PhotoSelectOptions.maxSelectNumber = 1;let photoPicker = new picker.PhotoViewPicker();photoPicker.select(PhotoSelectOptions).then(async (PhotoSelectResult) => {if (PhotoSelectResult.photoUris.length) {//复制图片到缓存目录（缓存目录才有读写权限）let filePath = PhotoSelectResult.photoUris[0]if (filePath) {//这里获取到的filePath 就是图片的路径}}

发送方调用 createImageSendMessage 方法传入图片的本地资源标志符 URI、设置是否发送原图以及接收方的用户 ID （群聊或聊天室分别为群组 ID 或聊天室 ID）创建图片消息，然后调用 sendMessage 方法发送该消息。SDK 会将图片上传至环信服务器，服务器自动生成图片缩略图。

这里imageFilePathOrUri 为上面获取到的filePath
// `imageFilePathOrUri` 为图片本地路径或者Uri。
let message = ChatMessage.createImageSendMessage(toChatUsername, imageFilePathOrUri);
// 会话类型，包含 `Chat`、`GroupChat` 和 `ChatRoom`，表示单聊、群聊或聊天室，默认为单聊。
message.setChatType(ChatType.GroupChat);
// 发送消息
ChatClient.getInstance().chatManager()?.sendMessage(message);

2、发送视频消息

① 缩略图获取

import picker from '@ohos.file.picker';
import {checkAppPermission} from '../../utils/permissions/CheckAccess'
import { common } from '@kit.AbilityKit';
import camerapicker from '@ohos.multimedia.cameraPicker';
import camera from '@ohos.multimedia.camera';
import { BusinessError } from '@ohos.base';
import { ChatMessage, } from 'easemob'
import  SendMessages from '../../presenter/SendMessage'
//全局公共样式
@Styles
function fillScreen() {.width('100%').backgroundColor(Color.White).borderRadius(20).padding(10)
}@CustomDialog
@Component
export struct AttachmentMessageDialog {@Prop conversationId: ResourceStr@Prop imgMsg: ChatMessage|undefined = undefinedchangeMessage = (imgMsg: ChatMessage|undefined)=> {}private controller: CustomDialogControllerprivate context = getContext(this) as common.UIAbilityContext; //UIAbilityContextbuild() {Column() {Row(){Image($r('app.media.ease_chat_takepic_pressed')).width(20).height(20)Text("相机").fontColor('#33b1ff')}.width('100%').padding({top:30,left:20,bottom:20}).onClick(async ()=>{this.camera()})Row(){}.width('100%').backgroundColor("#e7e9eb").height(1)Row(){Image($r('app.media.ease_chat_image_pressed')).width(20).height(20)Text("相册").fontColor('#33b1ff')}.width('100%').padding({top:20,left:20,bottom:20}).onClick(async () =>{this.photo()})Row(){}.width('100%').backgroundColor("#e7e9eb").height(1)Row(){Image($r('app.media.em_chat_video_pressed')).width(20).height(20)Text("视频").fontColor('#33b1ff')}.width('100%').padding({top:20,left:20,bottom:20}).onClick(async ()=>{ this.video()})Row(){}.width('100%').backgroundColor("#e7e9eb").height(1)Row(){Image($r('app.media.em_chat_card_normal')).width(20).height(20)Text("名片").fontColor('#33b1ff')}.width('100%').padding({top:20,left:20,bottom:20}).onClick( ()=>{})Row(){}.width('100%').backgroundColor("#e7e9eb").height(7)Row(){Text("取消").fontColor('#33b1ff')}.padding({top:20,left:20,bottom:20})}.width('100%')}private async photo(){//检查是否有读写外部媒体权限let res: boolean = await checkAppPermission(this.context)//无权限返回if (!res) return//从相册选择let PhotoSelectOptions = new picker.PhotoSelectOptions();PhotoSelectOptions.MIMEType = picker.PhotoViewMIMETypes.IMAGE_TYPE;PhotoSelectOptions.maxSelectNumber = 1;let photoPicker = new picker.PhotoViewPicker();photoPicker.select(PhotoSelectOptions).then(async (PhotoSelectResult) => {if (PhotoSelectResult.photoUris.length) {//复制图片到缓存目录（缓存目录才有读写权限）let filePath = PhotoSelectResult.photoUris[0]if (filePath) {SendMessages.sendImageMessage(this.conversationId+"", filePath).then((value)=>{this.changeMessage(value)})}}})}private async camera(){//检查是否有读写外部媒体权限let res: boolean = await checkAppPermission(this.context)//无权限返回if (!res) returntry {let pickerProfile: camerapicker.PickerProfile = {cameraPosition: camera.CameraPosition.CAMERA_POSITION_BACK};let pickerResult: camerapicker.PickerResult = await camerapicker.pick(this.context,[camerapicker.PickerMediaType.PHOTO, camerapicker.PickerMediaType.PHOTO], pickerProfile);if(pickerResult?.resultUri){}} catch (error) {let err = error as BusinessError;console.error(`the pick call failed. error code: ${err.code}`);}}private async video(){console.log(this.conversationId+"------")//检查是否有读写外部媒体权限let res: boolean = await checkAppPermission(this.context)//无权限返回if (!res) return//从相册选择let PhotoSelectOptions = new picker.PhotoSelectOptions();PhotoSelectOptions.MIMEType = picker.PhotoViewMIMETypes.VIDEO_TYPE;PhotoSelectOptions.maxSelectNumber = 1;let photoPicker = new picker.PhotoViewPicker();photoPicker.select(PhotoSelectOptions).then(async (PhotoSelectResult) => {if (PhotoSelectResult.photoUris.length) {//复制图片到缓存目录（缓存目录才有读写权限）let filePath = PhotoSelectResult.photoUris[0]if (filePath) {SendMessages.sendVideoMessage(this.conversationId+"", filePath,this.context).then((value)=>{this.changeMessage(value)})console.log("PhotoSelectOptions",filePath)}}})}
}

②发送方调用 createVideoSendMessage 方法传入接收方的用户 ID（群聊或聊天室分别为群组 ID 或聊天室 ID）、视频文件的本地路径、视频时长以及缩略图的本地存储路径，然后调用 sendMessage 方法发送消息。SDK 会将视频文件上传至消息服务器。若需要视频缩略图，你需自行获取视频首帧的路径，将该路径传入 createVideoSendMessage 方法。
上面获取到视频首诊

// 在应用层获取视频首帧
let thumbPath = this.getThumbPath(videoPath);
let message = ChatMessage.createVideoSendMessage(toChatUsername, videoPath, videoLength, thumbPath);
if (!message) {return;
}
// 会话类型，包含 `Chat`、`GroupChat` 和 `ChatRoom`，表示单聊、群聊或聊天室，默认为单聊。
message.setChatType(ChatType.GroupChat);
// 发送消息
ChatClient.getInstance().chatManager()?.sendMessage(message);

3、发送语音消息

①音频录制

// 音频录制
import { media } from '@kit.MediaKit';
import { BusinessError, systemDateTime } from '@kit.BasicServicesKit';
import fs from '@ohos.file.fs';
class AudioRecorder {private avRecorder: media.AVRecorder | undefined = undefined;public maxAmplitude: number = 0;public audioPath = ""private avProfile: media.AVRecorderProfile = {audioBitrate: 100000, // 音频比特率audioChannels: 2, // 音频声道数audioCodec: media.CodecMimeType.AUDIO_AAC, // 音频编码格式，当前只支持aacaudioSampleRate: 48000, // 音频采样率fileFormat: media.ContainerFormatType.CFT_MPEG_4A, // 封装格式，当前只支持m4a};private avConfig: media.AVRecorderConfig = {audioSourceType: media.AudioSourceType.AUDIO_SOURCE_TYPE_MIC, // 音频输入源，这里设置为麦克风profile: this.avProfile,url: 'fd://35', // 参考应用文件访问与管理开发示例新建并读写一个文件};// 注册audioRecorder回调函数setAudioRecorderCallback(): void {if (this.avRecorder !== undefined) {// 状态机变化回调函数this.avRecorder.on('stateChange', (state: media.AVRecorderState, _: media.StateChangeReason) => {console.log(`AudioRecorder current state is ${state}`);})// 错误上报回调函数this.avRecorder.on('error', (err: BusinessError) => {console.error(`AudioRecorder failed, code is ${err.code}, message is ${err.message}`);})}}// 开始录制对应的流程async startRecordingProcess(): Promise<void> {if (this.avRecorder !== undefined) {await this.avRecorder.release();this.avRecorder = undefined;}// 1.创建录制实例this.avRecorder = await media.createAVRecorder();this.setAudioRecorderCallback();// 2.获取录制文件fd赋予avConfig里的url；参考FilePicker文档const context = getContext(this);const path = context.filesDir;let currentTimeMillis: number = new Date().getTime();const filepath = path + '/' + currentTimeMillis + '.wav';this.audioPath = filepathconst file = fs.openSync(filepath, fs.OpenMode.READ_WRITE | fs.OpenMode.CREATE);const fdNumber = file.fd;this.avConfig.url = 'fd://' + fdNumber;// 3.配置录制参数完成准备工作await this.avRecorder.prepare(this.avConfig);// 4.开始录制await this.avRecorder.start();}// 暂停录制对应的流程async pauseRecordingProcess(): Promise<void> {if (this.avRecorder !== undefined && this.avRecorder.state === 'started') { // 仅在started状态下调用pause为合理状态切换await this.avRecorder.pause();}}// 恢复录制对应的流程async resumeRecordingProcess(): Promise<void> {if (this.avRecorder !== undefined && this.avRecorder.state === 'paused') { // 仅在paused状态下调用resume为合理状态切换await this.avRecorder.resume();}}// 停止录制对应的流程async stopRecordingProcess(): Promise<void> {if (this.avRecorder !== undefined) {// 1. 停止录制if (this.avRecorder.state === 'started'|| this.avRecorder.state === 'paused') { // 仅在started或者paused状态下调用stop为合理状态切换await this.avRecorder.stop();}// 2.重置await this.avRecorder.reset();// 3.释放录制实例await this.avRecorder.release();this.avRecorder = undefined;}}
}let audioRecorder = new AudioRecorder()
export default audioRecorder as AudioRecorder

②发送方调用 createVoiceSendMessage 方法传入接收方的用户 ID（群聊或聊天室分别为群组 ID 或聊天室 ID）、语音文件的路径和语音时长创建语音消息，然后调用 sendMessage 方法发送消息。SDK 会将语音文件上传至环信服务器

// `filePathOrUri` 为语音文件的本地路径或者文件的 URI，`duration` 为语音时长（单位为秒）。
let message = ChatMessage.createVoiceSendMessage(to, filePathOrUri, duration);
if (!message) {return;
}
// 设置会话类型，即`ChatMessage` 类的 `ChatType` 属性，包含 `Chat`、`GroupChat` 和 `ChatRoom`，表示单聊、群聊或聊天室，默认为单聊。
message.setChatType(ChatType.GroupChat);
// 发送消息
ChatClient.getInstance().chatManager()?.sendMessage(message);

二、接收附件消息

1、接收语音文件
接收方收到 onMessageReceived 回调，调用 getRemoteUrl 或 getLocalPath 方法获取语音文件的服务器地址或本地路径，从而获取语音文件。

let voiceBody = message.getBody() as VoiceMessageBody;
// 获取语音文件在服务器的地址。
let voiceRemoteUrl = voiceBody.getRemoteUrl();
// 本地语音文件的本地路径。
let voiceLocalPath = voiceBody.getLocalPath();

2、接收图片消息
接收方收到图片消息，自动下载图片缩略图。
SDK 默认自动下载缩略图，即 ChatOptions.setAutoDownloadThumbnail 设置为 true。若设置为手动下载缩略图，即 ChatOptions.setAutoDownloadThumbnail 设置为 false ，需调用 ChatClient.getInstance().chatManager()?.downloadThumbnail(message) 下载。
接收方收到 onMessageReceived 回调，调用 downloadAttachment 下载原图。

let msgListener: ChatMessageListener = {onMessageReceived: (messages: ChatMessage[]): void => {messages.forEach( message => {if (message.getType() === ContentType.IMAGE) {let callback: ChatCallback = {onSuccess: (): void => {// 附件下载成功},onError: (code: number, error: string): void => {// 附件下载失败},onProgress: (progress: number): void => {// 附件下载进度}}message.setMessageStatusCallback(callback);// 下载附件ChatClient.getInstance().chatManager()?.downloadAttachment(message);}})}
}

3、接收视频消息
接收方收到视频消息时，自动下载视频缩略图。
SDK 默认自动下载缩略图，即 ChatOptions.setAutoDownloadThumbnail 设置为 true 。若设置为手动下载缩略图，即 ChatOptions.setAutoDownloadThumbnail 设置为 false，需调用 ChatClient.getInstance().chatManager()?.downloadThumbnail(message) 下载。
接收方收到 onMessageReceived 回调，可以调用 ChatClient.getInstance().chatManager()?.downloadAttachment(message) 方法下载视频原文件

let msgListener: ChatMessageListener = {onMessageReceived: (messages: ChatMessage[]): void => {messages.forEach( message => {if (message.getType() === ContentType.VIDEO) {let callback: ChatCallback = {onSuccess: (): void => {// 附件下载成功},onError: (code: number, error: string): void => {// 附件下载失败},onProgress: (progress: number): void => {// 附件下载进度}}message.setMessageStatusCallback(callback);// 下载附件ChatClient.getInstance().chatManager()?.downloadAttachment(message);}})}
}

获取视频缩略图和视频原文件。

let body = message.getBody() as VideoMessageBody;
// 从服务器端获取视频文件。
let imgRemoteUrl = body.getRemoteUrl();
// 从服务器获取视频缩略图文件。
let thumbnailUrl = body.getThumbnailRemoteUrl();
// 从本地获取视频文件文件。
let localPath = body.getLocalPath();
// 从本地获取视频缩略图文件。
let localThumbPath = body.getThumbnailLocalPath();