Design of HarmonyOS Multi-Language Intelligent Input Method: Dynamic Switching of Subtypes and Real-Time Translation Function

{
  "module": {
    "extensionAbilities": [
      {
        "description": "InputMethodExtDemo",
        "icon": "Smedia:icon",
        "name": "InputMethodExtAbility",
        "srcEntry": "./ets/InputMethodExtensionAbility/InputMethodService.ts",
        "type": "inputMethod",
        "exported": true,
        "metadata": [
          {
            "name": "ohos.extension.input_method",
            "resource": "Sprofile:input_method_config"
          }
        ]
      }
    ]
  },
  "subtypes": [
    {
      "icon": "Smedia:icon",
      "id": "InputMethodExtAbility",
      "label": "$string:english",
      "locale": "en-US",
      "mode": "lower"
    },
    {
      "icon": "Smedia:icon",
      "id": "InputMethodExtAbility1",
      "label": "$string:chinese",
      "locale": "zh-CN",
      "mode": "lower"
    }
  ]
}

import { InputMethodSubtype, inputMethod } from '@kit.IMEKit';

export class KeyboardController {
  async switchCurrentInputMethodSubtype() {
    let subTypes = await inputMethod.getSetting().listCurrentInputMethodSubtype();
    let currentSubType = inputMethod.getCurrentInputMethodSubtype();
    for (let i = 0; i < subTypes.length; i++) {
      if (subTypes[i].id!== currentSubType.id) {
        await inputMethod.switchCurrentInputMethodSubtype(subTypes[i]);
      }
    }
  }
}

import { InputMethodSubtype, inputMethodEngine, inputMethod } from '@kit.IMEKit';

export class KeyboardController {
  async handleSubtypeChange() {
    let panel: inputMethodEngine.Panel;
    let inputMethodAbility: inputMethodEngine.InputMethodAbility = inputMethodEngine.getInputMethodAbility();
    inputMethodAbility.on('setSubtype', (inputMethodSubtype: InputMethodSubtype) => {
      if (inputMethodSubtype.id === 'InputMethodExtAbility') {
        panel.setUiContent('pages/Index');
      } else if (inputMethodSubtype.id === 'InputMethodExtAbility1') {
        panel.setUiContent('pages/Index1');
      }
    });
  }
}

async function translateText(text: string): Promise<string> {
  return new Promise((resolve, reject) => {
    // Here we simulate an asynchronous translation operation. In practical applications, a real translation API should be called.
    setTimeout(() => {
      resolve(`Translation result: ${text}`);
    }, 1000);
  });
}

import { FeatureAbility } from '@ohos.ability.featureAbility';

async function callTranslationService(text: string): Promise<string> {
  let want = {
    bundleName: 'com.example.translation',
    abilityName: 'TranslationServiceAbility'
  };
  try {
    let result = await FeatureAbility.callAbility(want, { text });
    return result;
  } catch (error) {
    console.error('Translation service call failed:', error);
    return '';
  }
}

callTranslationService('Hello').then((result) => {
  console.log('Translation result:', result);
  // Display the translation result on the input interface.
});

callTranslationService('Hello').catch((error) => {
  console.error('Translation failed:', error);
  // Display an error prompt to the user, such as popping up a dialog box to prompt "Translation failed. Please check the network connection."
});

// InputMethodService.ts
import { Want } from '@kit.AbilityKit';
import keyboardController from './model/KeyboardController';
import { InputMethodExtensionAbility } from '@kit.IMEKit';

export default class InputDemoService extends InputMethodExtensionAbility {
  onCreate(want: Want): void {
    keyboardController.onCreate(this.context);
  }

  onDestroy(): void {
    keyboardController.onDestroy();
  }
}

// KeyboardController.ts
import { display } from '@kit.ArkUT';
import { inputMethodEngine, InputMethodExtensionContext } from '@kit.IMEKit';

const inputMethodAbility: inputMethodEngine.InputMethodAbility = inputMethodEngine.getInputMethodAbility();

export class KeyboardController {
  private mContext: InputMethodExtensionContext | undefined = undefined;
  private panel: inputMethodEngine.Panel | undefined = undefined;
  private textInputClient: inputMethodEngine.InputClient | undefined = undefined;
  private keyboardController: inputMethodEngine.KeyboardController | undefined = undefined;

  constructor() {}

  public onCreate(context: InputMethodExtensionContext): void {
    this.mContext = context;
    this.initWindow();
    this.registerListener();
  }

  public onDestroy(): void {
    this.unRegisterListener();
    if (this.panel) {
      this.panel.hide();
      inputMethodAbility.destroyPanel(this.panel);
    }
    if (this.mContext) {
      this.mContext.destroy();
    }
  }

  public insertText(text: string): void {
    if (this.textInputClient) {
      this.textInputClient.insertText(text);
      // Trigger translation task
      this.translateText(text);
    }
  }

  public deleteForward(length: number): void {
    if (this.textInputClient) {
      this.textInputClient.deleteForward(length);
    }
  }

  private initWindow(): void {
    if (this.mContext === undefined) {
      return;
    }
    let dis = display.getDefaultDisplaySync();
    let dWidth = dis.width;
    let dHeight = dis.height;
    let keyHeightRate = 0.47;
    let keyHeight = dHeight * keyHeightRate;
    let nonBarPosition = dHeight - keyHeight;
    let panelInfo: inputMethodEngine.PanelInfo = {
      type: inputMethodEngine.PanelType.SOFT_KEYBOARD,
      flag: inputMethodEngine.PanelFlag.FLG_FIXED
    };
    inputMethodAbility.createPanel(this.mContext, panelInfo).then(async (inputPanel: inputMethodEngine.Panel) => {
      this.panel = inputPanel;
      if (this.panel) {
        await this.panel.resize(dWidth, keyHeight);
        await this.panel.moveTo(0, nonBarPosition);
        await this.panel.setUiContent('InputMethodExtensionAbility/pages/Index');
      }
    });
  }

  private registerListener(): void {
    this.registerInputListener();
  }

  private registerInputListener(): void {
    inputMethodAbility.on('inputStart', (kbController, textInputClient) => {
      this.textInputClient = textInputClient;
      this.keyboardController = kbController;
    });
    inputMethodAbility.on('inputStop', () => {
      this.onDestroy();
    });
  }

  private unRegisterListener(): void {
    inputMethodAbility.off('inputStart');
    inputMethodAbility.off('inputStop', () => {});
  }

  private async translateText(text: string): Promise<void> {
    try {
      let result = await callTranslationService(text);
      // Process and display the translation result
      console.log('Translation result:', result);
    } catch (error) {
      console.error('Translation failed:', error);
    }
  }
}

const keyboardController = new KeyboardController();
export default keyboardController;