使用onBackPress对子窗口进行销毁

showSubWindow() {  
  // 1.创建应用子窗口。 
  if (windowStage_ == null) { 
    console.error('Failed to create the subwindow. Cause: windowStage_ is null');} 
  else { 
    windowStage_.createSubWindow("mySubWindow", (err: BusinessError, data) => { 
      sub_windowClass = data; 
      console.info('Succeeded in creating the subwindow. Data: ' + JSON.stringify(data)); 
      // 2.子窗口创建成功后，设置子窗口的位置、大小及相关属性等。 
      sub_windowClass.moveWindowTo(300, 300); 
      sub_windowClass.resize(500, 500); 
      //可触属性可使得子窗口获焦 
      // sub_windowClass.setWindowTouchable(true) 
        // 3.为子窗口加载对应的目标页面。16        sub_windowClass.setUIContent("pages/Page"); 
      (sub_windowClass as window.Window).showWindow(); 
    }) 
  } 
}

import window from '@ohos.window' 
@Entry 
@Component 
struct Page { 
  @State message: string = 'Hello World' 
  onBackPress() { 
    console.log("被触发了"); 
    window.findWindow("mySubWindow").destroyWindow(); 
    return true; 
  } 
  build() { 
    Row() { 
      Column() { 
        Text(this.message) 
          .fontSize(50) 
          .fontWeight(FontWeight.Bold) 
      } 
      .width('100%') 
    } 
    .height('100%') 
      .backgroundColor(Color.Blue) 
  } 
  }