名称	描述
on(type: 'selectionCompleted', callback: Callback<SelectionInfo>): void	订阅划词完成事件，使用callback回调函数。
getSelectionContent(): Promise<string>	获取选中文本的内容。
createPanel(ctx: Context, info: PanelInfo): Promise<Panel>	创建划词面板。
show(): Promise<void>	显示面板。
hide(): Promise<void>	隐藏面板。
startMoving(): Promise<void>	使当前划词面板可以随鼠标拖动。
moveToGlobalDisplay(x: number, y: number): Promise<void>	移动划词面板至屏幕指定位置。

上述接口为本文档用到的核心接口，如需了解划词服务的全量接口，请参考selectionInput.SelectionExtensionAbility接口文档获取接口详细描述。

开发步骤

完整的工程示例详见SelectionAppSample。

创建划词应用工程。

1.1 打开DevEco Studio，点击"File>New>Create Project"创建一个Empty Ability，设备类型勾选"PC/2in1"。

1.2 在工程对应的ets目录下，右键选择"New>Directory"，新建两个目录，分别命名为selectionextability、models。

1.3 在selectionextability目录下，新建SelectionExtAbility.ets文件；在models目录下，新建SelectionModel.ets文件；在目录pages下，新建两个page文件MainPanel.ets和MenuPanel.ets。目录如下：
```
/src/main/
├── ets/
│   ├── models
│   |   └── SelectionModel.ets     # 划词模块管理类
│   ├── pages
│   |   ├── MainPanel.ets                    # 主面板
│   |   └── MenuPanel.ets                    # 菜单面板
│   └── selectionextability
│       └── SelectionExtAbility.ets     # 划词扩展类
├── resources/base/profile/main_pages.json
├── module.json5                             # 配置文件
```

在SelectionModel.ets文件中，开发者可自定义划词模块管理类，用于统一管理划词内容、窗口等信息。并且实现一些get、set接口，便于信息的类间传递。

import { selectionManager, SelectionExtensionContext } from '@kit.BasicServicesKit';
import { hilog } from '@kit.PerformanceAnalysisKit';

export class SelectionModel {
  private selectionInfo: selectionManager.SelectionInfo | undefined;
  private selectionContent: string | undefined;
  private selectionPanel: selectionManager.Panel | undefined;
  private context: SelectionExtensionContext | undefined;
  private listener: (selectionInfo: selectionManager.SelectionInfo) => void;

  private constructor() {
    this.selectionInfo = undefined;
    this.selectionContent = undefined;
    this.selectionPanel = undefined;
    this.context = undefined;
    this.listener = (selectionInfo: selectionManager.SelectionInfo) => {
      hilog.info(0x0000, 'SelectionModel', `Received selection selectionInfo: ${selectionInfo}`);
    }
  }

  public static getInstance(): SelectionModel {
    if (globalThis.instance == null) {
      globalThis.instance = new SelectionModel();
    }
    return globalThis.instance;
  }

  public getSelectionInfo(): selectionManager.SelectionInfo | undefined {
    return this.selectionInfo;
  }

  public setSelectionInfo(selectionInfo: selectionManager.SelectionInfo) {
    this.selectionInfo = selectionInfo;
  }

  public getSelectionContent(): string | undefined {
    return this.selectionContent;
  }

  public setSelectionContent(selectionContent: string) {
    this.selectionContent = selectionContent;
  }

  public getSelectionPanel(): selectionManager.Panel | undefined {
    return this.selectionPanel;
  }

  public setSelectionPanel(selectionPanel: selectionManager.Panel | undefined) {
    this.selectionPanel = selectionPanel;
  }

  public getContext(): SelectionExtensionContext | undefined {
    return this.context;
  }

  public setContext(context: SelectionExtensionContext) {
    this.context = context;
  }

  public registerListener(listener: (selectionInfo: selectionManager.SelectionInfo) => void) {
    this.listener = listener;
  }
}

在SelectionExtAbility.ets文件中，开发者可实现扩展能力类。该类需要继承SelectionExtensionAbility，用于划词扩展生命周期的管理。

import { selectionManager, SelectionExtensionAbility} from '@kit.BasicServicesKit';
import { Want } from '@kit.AbilityKit';
import { rpc } from '@kit.IPCKit';

class SelectionAbilityStub extends rpc.RemoteObject {
  constructor(des: string) {
    super(des);
  }

  onRemoteMessageRequest(
    code: number,
    data: rpc.MessageSequence,
    reply: rpc.MessageSequence,
    options: rpc.MessageOption
  ): boolean | Promise<boolean> {
    return true;
  }
}

class SelectionExtAbility extends SelectionExtensionAbility {
  private panel_: selectionManager.Panel | undefined = undefined;

  onConnect(want: Want): rpc.RemoteObject {
    // 当SelectionExtensionAbility实例完成创建时，系统会触发该回调。开发者可在该回调中执行初始化逻辑（如定义变量、加载资源、监听划词事件等）。
    return new SelectionAbilityStub('remote');
  }

  onDisconnect(): void {
    // 当SelectionExtensionAbility实例被销毁（例如用户关闭划词开关或切换划词应用）时，系统触发该回调。开发者可以在该生命周期中执行资源清理、数据保存等相关操作。
    selectionManager.destroyPanel(this.panel_);
  }
}

export default SelectionExtAbility;

上述代码中，划词扩展被拉起时会触发onConnect回调，可以在该回调中监听划词事件，完成划词窗口的创建、窗口内容的设定、窗口的移动、窗口的显示和隐藏等操作；当划词扩展退出时会触发onDisconnect回调，可以在该回调中完成窗口销毁的操作。详细内容可参见下面第4步。

在划词扩展被拉起时，可以提前创建划词窗口（但不调用show接口），以缩短用户在第一次划词时的响应延迟。同时，可以在onConnect中监听划词事件，执行后续的弹窗操作。通过监听selectionCompleted获取SelectionInfo其中包含了划词操作的起始和结束坐标等信息。通过调用getSelectionContent接口获取划词内容。

import { selectionManager, PanelInfo, PanelType, SelectionExtensionAbility } from '@kit.BasicServicesKit';
import { SelectionModel } from '../models/SelectionModel';
import { Want } from '@kit.AbilityKit';
import { rpc } from '@kit.IPCKit';
import { hilog } from '@kit.PerformanceAnalysisKit';

class SelectionAbilityStub extends rpc.RemoteObject {
  constructor(des: string) {
    super(des);
  }

  onRemoteMessageRequest(
    code: number,
    data: rpc.MessageSequence,
    reply: rpc.MessageSequence,
    options: rpc.MessageOption
  ): boolean | Promise<boolean> {
    return true;
  }
}

class SelectionExtAbility extends SelectionExtensionAbility {
  private panel_: selectionManager.Panel | undefined = undefined;

  onConnect(want: Want): rpc.RemoteObject {
    SelectionModel.getInstance().setContext(this.context);
    selectionManager.on('selectionCompleted', async (info: selectionManager.SelectionInfo) => {
      if (this.panel_ == undefined) {
        await this.createSelectionPanel();
      }
      this.onSelected(info);
    });
    return new SelectionAbilityStub('remote');
  }

  onDisconnect(): void {
    selectionManager.destroyPanel(this.panel_);
  }

  async createSelectionPanel() {
    let panelInfo: PanelInfo = {
      panelType: PanelType.MENU_PANEL,
      x: 0,
      y: 0,
      width: 500,
      height: 300
    }
    try {
      let panel: selectionManager.Panel = await selectionManager.createPanel(this.context, panelInfo);    // 创建菜单面板
      this.panel_ = panel;
      try {
        panel.on('hidden', () => {    // 监听弹窗隐藏（窗口失焦时会触发隐藏）
          hilog.info(0x0000, 'SelectionExtensionAbility', 'panel has hidden.');
        })
      } catch (error) {
        hilog.error(0x0000, 'SelectionExtensionAbility', 'Failed to listen panel hidden');
      }
      try {
        await panel.setUiContent('pages/MenuPanel')   // 设置菜单面板样式
        hilog.info(0x0000, 'SelectionExtensionAbility', 'Succeed to setUiContent [pages/MenuPanel].');
      } catch (error) {
        hilog.error(0x0000, 'SelectionExtensionAbility', `Failed to setUiContent, error: ${JSON.stringify(error)}`);
      }
    } catch(error) {
      hilog.error(0x0000, 'SelectionExtensionAbility', `Failed to createPanel, error: ${JSON.stringify(error)}`);
    }
  }

  async onSelected(info: selectionManager.SelectionInfo) {
    SelectionModel.getInstance().setSelectionInfo(info);
    try {
      let content = await selectionManager.getSelectionContent();   // 获取划词内容
      SelectionModel.getInstance().setSelectionContent(content);
    } catch (error) {
      hilog.error(0x0000, 'SelectionExtensionAbility', `Failed to get selection content: ${JSON.stringify(error)}`);
      return;
    }
    if (!this.panel_) {
      hilog.info(0x0000, 'SelectionExtensionAbility', 'Panel is not created yet.');
      return;
    }
    try {
      await this.panel_.moveToGlobalDisplay(info.startDisplayX, info.startDisplayY)    // 将弹窗移动到用户鼠标划词的起始点
      hilog.info(0x0000, 'SelectionExtensionAbility', 'Move succeed.');
    } catch (error) {
      hilog.error(0x0000, 'SelectionExtensionAbility', `Failed to move, error: ${JSON.stringify(error)}`);
      return;
    }

    try {
      await this.panel_.show()    // 显示弹窗
      hilog.info(0x0000, 'SelectionExtensionAbility', 'Show succeed.');
    } catch (error) {
      hilog.error(0x0000, 'SelectionExtensionAbility', `Failed to show panel, error: ${JSON.stringify(error)}`);
      return;
    }
  }
}

export default SelectionExtAbility;

在MenuPanel.ets文件中，开发者可根据业务内容自主实现菜单面板的显示效果，例如提供翻译、查询、扩写等按钮。并且可以通过绑定点击事件，弹出不同的主面板，以展示不同的内容。本示例仅提供了一个简单的点击按钮，用于展示如何弹出主面板。

import { SelectionModel } from '../models/SelectionModel';
import { selectionManager, PanelInfo, BusinessError, PanelType, SelectionExtensionContext } from '@kit.BasicServicesKit';
import { hilog } from '@kit.PerformanceAnalysisKit';
import { Want } from '@kit.AbilityKit';

@Entry
@Component
struct MenuPanel {
  @State message: string = 'MenuPanel';
  selectionInfo: selectionManager.SelectionInfo | undefined = undefined;

  CreateMainPanel() {
    this.selectionInfo = SelectionModel.getInstance().getSelectionInfo();
    let existingPanel = SelectionModel.getInstance().getSelectionPanel();
    if (existingPanel !== undefined) {
      try {
        existingPanel.show();
      } catch (error) {
        SelectionModel.getInstance().setSelectionPanel(undefined);
      }
      return;
    }
    let panelInfo: PanelInfo = {
      panelType: PanelType.MAIN_PANEL,
      x: 0,
      y: 0,
      width: 1500,
      height: 1000
    }
    selectionManager.createPanel(SelectionModel.getInstance().getContext(), panelInfo)
      .then(async (panel: selectionManager.Panel) => {
        SelectionModel.getInstance().setSelectionPanel(panel);
        hilog.info(0x0000, 'SelectionExtensionAbility', 'Succeed to create main panel');
        if (this.selectionInfo !== undefined) {
          panel.moveToGlobalDisplay(this.selectionInfo.startDisplayX + 100, this.selectionInfo.startDisplayY + 100);
        }
        try {
          panel.on('destroyed', () => {
            hilog.info(0x0000, 'SelectionExtensionAbility', 'panel has destroyed');
            SelectionModel.getInstance().setSelectionPanel(undefined);
          })
        } catch (error) {
          hilog.error(0x0000, 'SelectionExtensionAbility', 'Failed to listen window destroy');
        }
        try {
          await panel.setUiContent('pages/MainPanel');
          hilog.info(0x0000, 'SelectionExtensionAbility', 'Succeed to setUiContent [pages/MainPanel].');
        } catch (error) {
          hilog.error(0x0000, 'SelectionExtensionAbility', `Failed to setUiContent of main panel, error: [${JSON.stringify(error)}]`);
          return;
        }

        try {
          await panel.show();
          hilog.info(0x0000, 'SelectionExtensionAbility', 'Succeed to show main panel.');
        } catch (error) {
          hilog.error(0x0000, 'SelectionExtensionAbility', `Failed to show main panel, error: [${JSON.stringify(error)}]`);
        }
      })
      .catch((error: BusinessError) => {
        hilog.error(0x0000, 'SelectionExtensionAbility', `Failed to createPanel, error: [${JSON.stringify(error)}]`);
        return;
      });
  }

  startEntryAbility() {   // 拉起应用
    let wantAbility: Want = {
      bundleName: 'com.selection.selectionapplication',   // 应用的bundleName
      abilityName: 'EntryAbility',    // 应用的abilityName
    };
    let context: SelectionExtensionContext | undefined = SelectionModel.getInstance().getContext();
    if (context !== undefined) {
      context.startAbility(wantAbility)
        .then(() => {
          hilog.info(0x0000, 'SelectionExtensionAbility', `startAbility success, want: ${wantAbility.abilityName}`);
        })
        .catch((error: BusinessError) => {
          hilog.error(0x0000, 'SelectionExtensionAbility', `startAbility failed, error: ${JSON.stringify(error)}`);
        })
    }
  }

  build() {
    Column() {
      Button('click to show MAIN_PANEL')
        .onClick(() => {
          this.CreateMainPanel();
        })
      Button('start EntryAbility')
        .onClick(() => {
          this.startEntryAbility();
        })
    }
    .backgroundColor('#AAFFFF')
    .height('100%')
    .width('100%')
  }
}

在MainPanel.ets文件中，开发者可根据业务场景，自行实现主面板的显示效果。本示例仅提供了一个简单的展示划词内容的主面板，具体的业务侧功能需要开发者自行实现。

import { SelectionModel } from '../models/SelectionModel';
import { selectionManager } from '@kit.BasicServicesKit';
@Entry
@Component
struct MainPanel {
  @State message: string = 'MainPanel';

  aboutToAppear(): void {
    let content: string | undefined = SelectionModel.getInstance().getSelectionContent();
    if (content !== undefined) {
      this.message = content;
    }
  }

  build() {
    RelativeContainer() {
      Text(this.message)
        .id('MainPanelHelloWorld')
        .fontSize(8)
        .alignRules({
          center: { anchor: '__container__', align: VerticalAlign.Center },
          middle: { anchor: '__container__', align: HorizontalAlign.Center }
        })
    }
    .onTouch((event: TouchEvent) => {
      if (event.type === TouchType.Down) {
        let selectionPanel: selectionManager.Panel | undefined = SelectionModel.getInstance().getSelectionPanel();
        if (selectionPanel !== undefined) {
          selectionPanel.startMoving();   // 调用selectionManager提供的startMoving接口可实现划词面板随鼠标拖动
        }
      }
    })
    .backgroundColor('#AAA000')
    .height('100%')
    .width('100%')
  }
}

配置main_pages.json文件。

在..\resources\base\profile\main_pages.json文件中的src字段中添加新增的MainPanel和MenuPanel页面。
```
"src": [
    "pages/MainPanel",
    "pages/MenuPanel"
]
```

配置module.json5文件。

在extensionAbilities字段中配置划词扩展类文件路径。

"extensionAbilities": [
  {
    "name": "SelectionExtAbility",
    "srcEntry": "./ets/selectionextability/SelectionExtAbility.ets",
    "type": "selection",
    "exported": false,
  }
]

配置签名。

点击DevEco Studio右上角的"Project Structure"按钮，点击"Signing Configs"按钮，按操作登录华为账号后会自动生成签名。

调测验证

连接设备后，点击DevEco Studio右上角的绿色三角形"Run entry"按钮，编译器会执行编译并自动将应用安装到设备中。
设置划词服务的系统参数。

2.1 进入设置-->系统-->智慧划词界面打开智慧划词开关。

2.2 选择当前应用为划词应用。

2.3 选择划词触发方式为“点击ctrl键显示”。
通过日志观察划词服务拉起划词扩展能力的过程。

使用DevEco Studio的Hilog窗口查看日志。
使用鼠标左键双击、三击或拖动选中文本后，键盘点击ctrl键，观察菜单面板的弹出。点击菜单面板上的按钮，观察主面板的弹出。

目录

实现一个划词扩展能力

接口说明

开发步骤

调测验证