Building applications for OpenHarmony with Rust

openharmony-ability is a crate to manage OpenHarmony application's activity with rust, be similar to android-activity. This project is in progress, and the API is not stable. yet!

OpenHarmony Ability

This project is in progress, and the API is not stable.

openharmony-ability is a crate to manage OpenHarmony application's activity with rust, be similar to android-activity.

Architecture

The architecture of OpenHarmony is similar to Node.js, where we need to manage the application's lifecycle via callbacks. Hence, there are a few key points to keep in mind.

1. Don't block the main thread as it can lead to application freezing and crashing.

2. openharmony-ability's run_loop doesn't retain the resource and ownership, so if you create a new resource, you should leak it to prevent NULL pointer.

We provide some packages or crates to help you develop OpenHarmony application with Rust.

ArkTS

We need a entry-point to start the application, and we use ArkTS to manage the application's lifecycle.

• @ohos-rs/ability
  All of ability need to extend RustAbility and all lifecycle need to call super.xx to make sure the ability can work normally.

Rust

• openharmony-ability
  Basic crate to manage the application's lifecycle.

• openharmony-ability-derive
  Macro to generate the ability's implementation.

Usage

1. use ohrs to init project and add openharmony-ability dependencies.

ohrs init hello

cargo add openharmony-ability
cargo add openharmony-ability-derive

1. Add the follow code to lib.rs.

use ohos_hilog_binding::hilog_info;
use openharmony_ability::App;
use openharmony_ability_derive::ability;

#[ability]
fn openharmony_app(app: App) {
    app.run_loop(|types| {
        hilog_info!(format!("ohos-rs macro: {:?}", types.as_str()).as_str());
    });
}

Note: ohos_hilog_binding is a optional dependency and you can add or remove it.

1. Add @ohos-rs/ability to your OpenHarmony/HarmonyNext project.

ohpm install @ohos-rs/ability

1. change the EntryAbility.ets file to the follow code:

import { RustAbility } from "@ohos-rs/ability";
import Want from "@ohos.app.ability.Want";
import { AbilityConstant } from "@kit.AbilityKit";

export default class EntryAbility extends RustAbility {
  public moduleName: string = "example";

  async onCreate(
    want: Want,
    launchParam: AbilityConstant.LaunchParam
  ): Promise<void> {
    // Note: you should call super.onCreate to make sure the ability can work normally.
    super.onCreate(want, launchParam);
  }
}

1. Change the moduleName to your rust project name. For example, we need to change it with hello in this project.

2. Build your rust project and copy the dynamic library to (Open-)Harmony(Next) project.

3. Now, you can enjoy it.

Here is the end result sample here!

Source code is available for exploration