设置隐私模式不是一定要在@entry装饰的自定义组件。可参考如下代码：

import { uiObserver, window } from '@kit.ArkUI';
import { BusinessError } from '@kit.BasicServicesKit';

// 该示例演示NavDestination的生命周期时序。
@Component
struct PageOneComponent {
  private stack: NavPathStack | null = null;
  @State eventStr: string = "";
  @State message:string = ''
  @State isPrivacyMode: boolean = true;

  /**
   * 设置窗口隐私的方法
   */
  setPrivacyMode(){
    try {
      window.getLastWindow(getContext(), (err: BusinessError, data) => {
        const errCode = err.code;
        if (errCode) {
          return;
        }
        let promise = data.setWindowPrivacyMode(this.isPrivacyMode);
        promise.then(() => {
          this.message = "隐私模式";
          console.log('已成功将窗口设置为隐私模式.');
        }).catch((err: BusinessError) => {
          console.error('Failed to set the window to privacy mode. Cause: ' + JSON.stringify(err));
        });
      })

    } catch (exception) {
      console.error('Failed to set the window to privacy mode. Cause:' + JSON.stringify(exception));
    }
  }

  build() {
    NavDestination() {
      Column({space:10}) {
        Text("event: " + this.eventStr)
        Button('pushPath', { stateEffect: true, type: ButtonType.Capsule })
          .width('80%')
          .height(40)
          .margin(20)
          .onClick(() => {
            if (this.stack) {
              this.stack.pushPath({ name: "pageOne" });
            }
          })
        Button('pop', { stateEffect: true, type: ButtonType.Capsule })
          .width('80%')
          .height(40)
          .margin(20)
          .onClick(() => {
            this.stack?.pop()
          })

        Button('设置隐私').onClick(()=>{
          this.setPrivacyMode()
        })
      }
      .width('100%')
      .height('100%')
    }
    .title('pageOne')
    .onAppear(() => {
      this.eventStr += "<onAppear>";
    })
    .onDisAppear(() => {
      this.eventStr += "<onDisAppear>";
    })
    .onShown(() => {
      this.eventStr += "<onShown>";
    })
    .onHidden(() => {
      this.eventStr += "<onHidden>";
    })
    .onWillAppear(() => {
      this.eventStr += "<onWillAppear>";
    })
    .onWillDisappear(() => {
      this.eventStr += "<onWillDisappear>";
    })
    .onWillShow(() => {
      this.eventStr += "<onWillShow>";
    })
    .onWillHide(() => {
      this.eventStr += "<onWillHide>";
    })
    // onReady会在onAppear之前调用
    .onReady((ctx: NavDestinationContext) => {
      try {
        this.eventStr += "<onReady>";
        this.stack = ctx.pathStack;
      } catch (e) {
        console.log(`testTag onReady catch exception: ${JSON.stringify(e)}`)
      }
    })
  }
}

@Entry
@Component
struct NavigationExample3 {
  private stack: NavPathStack = new NavPathStack();

  aboutToAppear(): void {
    console.log("aboutToAppear")
  }

  @Builder
  PageMap(name: string) {
    if (name === 'pageOne') {
      PageOneComponent()
    }
  }

  build() {
    Navigation(this.stack) {
      Stack({ alignContent: Alignment.Center }) {
        Button('pushPath', { stateEffect: true, type: ButtonType.Capsule })
          .width('80%')
          .height(40)
          .margin(20)
          .onClick(() => {
            this.stack.pushPath({ name: "pageOne" })
          })
      }
      .width('100%')
      .height('100%')
    }
    .width('100%')
    .height('100%')
    .navDestination(this.PageMap)
    .title('Navigation')
  }
}