Development Environment

The official IDE for HarmonyOS is DevEco Studio, which, like Android Studio, is built upon the open-source IntelliJ IDEA Community Edition from JetBrains. The user interface is nearly identical to what Android developer are already familiar with.
Currantly, DevEco Studio only supports Windows; Mac users will need a Windows virtual machine. Once installed, the SDK can be downloaded directly without any special network configuration—a smoother experience compared to Android development in some regions.

Build System and Virtual Devices

Gradle serves as the build tool, exactly as in Android projects.
For running and debugging apps, there is no local emulator provided. Instead, you must register a Huawei developer account and add a remote virtual device through the Virtual Machine Manager.

Project Structure

• entry directory – the default module, analogous to the app module in Android.
• entry/src/main/java – application source code, while src/test holds unit tests, just like Android.
• entry/src/main/resource – resource directory, equivalent to Android’s src/main/res.
• entry/src/main/config.json – project and entry configuration, comparable to AndroidManifest.xml. It declares the package name, required system permissions, and the entry-point pages.

Core Concepts

• Ability: Similar to an Android Activity. The default entry is MainAbility.
• AbilitySlice: Comparable to a Fragment; it manages the UI layout binding.
• AbilityPackage: Analogous to the Android Application class, representing the entire application.
• HVD (HarmonyOS Virtual Device): Like an AVD (Android Virtual Device), but accessed remotely.
• HAP (HarmonyOS Ability Package): The installation package extension, serving the same purpose as .apk files in Android.

Code Examples

MainAbility (Activity)

package com.example.myharmonyapp;

import com.example.myharmonyapp.slice.MainAbilitySlice;
import ohos.aafwk.ability.Ability;
import ohos.aafwk.content.Intent;

public class MainAbility extends Ability {
    @Override
    public void onStart(Intent intent) {
        super.onStart(intent);
        super.setMainRoute(MainAbilitySlice.class.getName());
    }
}

AbilitySlice (Fragment equivalent)

package com.example.myharmonyapp.slice;

import com.example.myharmonyapp.data.UiHolder;
import ohos.aafwk.ability.AbilitySlice;
import ohos.aafwk.content.Intent;

public class MainAbilitySlice extends AbilitySlice {
    private UiHolder uiHolder;

    @Override
    public void onStart(Intent intent) {
        uiHolder = new UiHolder(this);
        setUIContent(uiHolder.buildComponent());
    }

    @Override
    public void onActive() {
        super.onActive();
    }

    @Override
    public void onForeground(Intent intent) {
        super.onForeground(intent);
    }
}

Layout example: horizontal split

<?xml version="1.0" encoding="utf-8"?>
<DirectionalLayout
    xmlns:ohos="http://schemas.huawei.com/res/ohos"
    ohos:width="match_parent"
    ohos:height="56vp"
    ohos:orientation="horizontal">

    <Text
        ohos:id="$+id:left_label"
        ohos:width="match_content"
        ohos:height="match_content"
        ohos:weight="1"
        ohos:text_alignment="center"
        ohos:text_size="16fp"
        ohos:text="Left"
    />

    <Text
        ohos:id="$+id:right_label"
        ohos:width="match_content"
        ohos:height="match_content"
        ohos:weight="1"
        ohos:text_alignment="center"
        ohos:text_size="16fp"
        ohos:text="Right"
    />
</DirectionalLayout>

For Android developers, the learning curve for HarmonyOS is negligible. The API design shows clear Android influences, making the transition smooth. The platform offers a familiar structure and a friendly development experience.