Developing a Smart Community Life Assistant Based on HarmonyOS Next

In the era of ubiquitous connectivity, HarmonyOS Next revolutionizes the development experience for lifestyle service applications. This article combines AppGallery Connect (AGC) services with ArkTS to guide you in building a comprehensive smart community assistant application, covering core scenarios like community services, smart home control, and neighborhood social features—making lifestyle app development simple and efficient.

1. Project Blueprint and Foundation Setup

Tech Stack:

HarmonyOS SDK 5.0
ArkTS Declarative UI
AGC Core Services: Cloud DB, Auth Service, Cloud Functions

Three-Step Initialization:

Create an AGC project and enable Cloud DB
Design community service data structures
Configure HarmonyOS app permissions

// CommunityService.ets - Data Model  
@Observed  
export class CommunityService {  
  @PrimaryKey id: string = '';      // Unique service ID  
  title: "string = '';               // Service title (e.g., \"Parcel Receiving\")  "
  description: "string = '';         // Service description  "
  icon: Resource = $r('app.media.default_icon'); // Service icon  
  contact: string = '';             // Contact number  
}

2. Community Information Service Implementation

Core Features:

Real-time property announcements
Community event calendar
Emergency alert system

// NoticeManager.ets - Announcement Module  
import { cloudDB } from '@kit.AGConnectCloudDBKit';  

export class NoticeManager {  
  private static cloudDBZone: cloudDB.CloudDBZone | null = null;  

  // Initialize Cloud DB  
  static async init() {  
    try {  
      const agcCloudDB = await cloudDB.getAGConnectCloudDB();  
      this.cloudDBZone = await agcCloudDB.openCloudDBZone(  
        new cloudDB.CloudDBZoneConfig('CommunityZone')  
      );  
    } catch (err) {  
      console.error('Cloud DB init failed', err.message);  
    }  
  }  

  // Get latest notice  
  static async getLatestNotice(): Promise<string> {  
    const query = cloudDB.CloudDBZoneQuery.where(CommunityNotice)  
      .orderByDesc('publishTime')  
      .limit(1);  

    const snapshot = await this.cloudDBZone.executeSnapshotQuery(query);  
    if (snapshot.hasNext()) {  
      return (await snapshot.next()).content;  
    }  
    return 'No announcements';  
  }  

  // Send emergency alert (Property management use)  
  static async sendEmergencyAlert(message: string) {  
    const alert = new CommunityNotice();  
    alert.id = generateUUID();  
    alert.content = `[URGENT] ${message}`;  
    await this.cloudDBZone?.upsertData([alert]);  
  }  
}

3. Smart Home Control Center

Scenario: Control smart devices via phone

// SmartHomeController.ets  
import { smarthome } from '@kit.ConnectedHomeKit';  

@Entry  
@Component  
struct HomeControlPanel {  
  @State lightsStatus: boolean = false;  
  @State temperature: number = 24;  

  // Load devices  
  private async loadDevices() {  
    const devices = await smarthome.getDeviceList();  
    devices.forEach(device => {  
      if (device.deviceType === 'LIGHT') {  
        this.lightsStatus = device.status === 'ON';  
      }  
    });  
  }  

  // Toggle lights  
  private async toggleLights() {  
    await smarthome.executeCommand({  
      deviceType: 'LIGHT',  
      command: this.lightsStatus ? 'TURN_OFF' : 'TURN_ON'  
    });  
    this.lightsStatus = !this.lightsStatus;  
  }  

  build() {  
    Column() {  
      // Light control card  
      ControlCard({  
        icon: $r('app.media.light_icon'),  
        title: 'Living Room Lights',  
        status: this.lightsStatus ? 'ON' : 'OFF',  
        onToggle: () => this.toggleLights()  
      })  

      // Temperature controller  
      TemperatureSlider({  
        currentTemp: this.temperature,  
        onTempChange: (newTemp) => { this.temperature = newTemp }  
      })  
    }  
    .onAppear(() => this.loadDevices())  
  }  
}  

// Temperature control component  
@Component  
struct TemperatureSlider {  
  @Link currentTemp: number;  
  build() {  
    Row() {  
      Image($r('app.media.temp_icon')).width(30)  
      Slider({ value: this.currentTemp, min: 16, max: 30 })  
        .onChange(v => this.currentTemp = v)  
      Text(`${this.currentTemp}°C`).fontSize(18)  
    }  
  }  
}

4. Neighborhood Social Features

Key Features:

Community chat rooms
Second-hand marketplace
Skill exchange platform

// NeighborChat.ets - Community Chat  
import { agconnect } from '@kit.AGConnectCoreKit';  

@Entry  
@Component  
struct CommunityChatRoom {  
  @State messages: ChatMessage[] = [];  
  @State newMessage: string = '';  
  private chatRoomId: string = 'community_main';  

  // Send message  
  private async sendMessage() {  
    const user = agconnect.auth().currentUser;  
    await cloud.function('sendChatMessage').call({  
      roomId: this.chatRoomId,  
      message: {  
        sender: user?.displayName || 'Anonymous Neighbor',  
        content: this.newMessage  
      }  
    });  
    this.newMessage = '';  
  }  

  // Real-time message listener  
  onInit() {  
    cloud.function('subscribeToChat').call({ roomId: this.chatRoomId })  
      .on('message', (event) => {  
        this.messages = [...this.messages, event.data];  
      });  
  }  

  build() {  
    Column() {  
      // Message list  
      List({ space: 10 }) {  
        ForEach(this.messages, (msg) => {  
          ListItem() { ChatBubble({ message: msg }) }  
        })  
      }  
      .layoutWeight(1)  

      // Input area  
      Row() {  
        TextInput({ text: this.newMessage })  
          .onChange(v => this.newMessage = v)  
          .layoutWeight(1)  
        Button('Send').onClick(() => this.sendMessage())  
      }  
    }  
  }  
}

5. Convenient Payment System

Features:

Utility bill queries
Online payments
Payment history

// PaymentService.ets  
import { pay } from '@kit.PaymentKit';  

export class PaymentManager {  
  // Retrieve pending bills  
  static async getPendingBills(userId: string): Promise<UtilityBill[]> {  
    const query = cloudDB.CloudDBZoneQuery.where(UtilityBill)  
      .equalTo('userId', userId)  
      .equalTo('isPaid', false);  

    const snapshot = await this.cloudDBZone.executeSnapshotQuery(query);  
    return await snapshot.getAllObjects();  
  }  

  // Pay bill  
  static async payBill(billId: string) {  
    const bill = await this.getBillById(billId);  
    const result = await pay.requestPayment({  
      amount: bill.amount,  
      description: `${bill.type} bill`  
    });  

    if (result.code === 0) {  
      await this.markBillAsPaid(billId);  
      return true;  
    }  
    return false;  
  }  

  // Mark bill as paid  
  private static async markBillAsPaid(billId: string) {  
    const bill = await this.getBillById(billId);  
    bill.isPaid = true;  
    await this.cloudDBZone.upsertData([bill]);  
  }  
}

6. Seamless Multi-Device Experience

Cross-Device Scenario:

View parcels on watch → Pay fees on phone → Check events on tablet

// Distributed Express Info Sync  
import { distributedKVStore } from '@kit.DistributedDataManagerKit';  

// Phone (Send parcel info)  
async function saveExpressInfo(info: ExpressInfo) {  
  const kvManager = await distributedKVStore.createKVManager();  
  const store = await kvManager.getKVStore('express_store');  
  await store.put('latest_express', JSON.stringify(info));  
}  

// Watch (Receive parcel info)  
@Entry  
@Component  
struct WatchExpressView {  
  @State expressInfo: ExpressInfo | null = null;  

  onInit() {  
    distributedKVStore.createKVManager()  
      .getKVStore('express_store')  
      .on('dataChange', 'latest_express', (data) => {  
        this.expressInfo = JSON.parse(data.value);  
      });  
  }  

  build() {  
    Column() {  
      if (this.expressInfo) {  
        Text(`Courier: ${this.expressInfo.company}`)  
        Text(`Status: ${this.expressInfo.status}`)  
      }  
    }  
  }  
}

7. Privacy and Security

Key Measures:

Data Minimization

   async function requestNecessaryPermissions() {  
     const permissions: Array<Permissions> = [  
       'ohos.permission.READ_CONTACTS', // Neighborhood contacts  
       'ohos.permission.LOCATION'      // Community services  
     ];  
     const result = await abilityAccessCtrl  
       .createAtManager()  
       .requestPermissionsFromUser(getContext(), permissions);  
     return result.permissions.every(p => p.granted);  
   }

End-to-Cloud Encryption

   <!-- security_config.xml -->  
   <security-config>  
     <domain-config cleartextTrafficPermitted="false">  
       <domain>community-api.example.com</domain>  
       <trust-anchors>  
         <certificates src="@raw/security_cert"/>  
       </trust-anchors>  
     </domain-config>  
   </security-config>

Data Masking

   function maskPhoneNumber(phone: string): string {  
     return phone.replace(/(\d{3})\d{4}(\d{4})/, '$1****$2');  
   }

8. Expansion Scenarios

Community AI Assistant

   import { ai } from '@kit.AIKit';  
   const assistant = ai.createConversationAssistant();  
   assistant.on('response', (event) => {  
     showResponse(event.text);  
   });

Smart Waste Sorting

   camera.takePhoto().then(photo => {  
     ai.imageRecognition(photo).then(result => {  
       showGarbageCategory(result.objectName);  
     });  
   });

Shared Tool Reservation

   async function reserveTool(toolId: string) {  
     const result = await booking.createReservation({  
       itemId: toolId,  
       timeSlot: '2023-11-15 14:00'  
     });  
     return result.status === 'CONFIRMED';  
   }