HarmonyOS 关于NavPathStack疑问

1.根页面的监听，可以通过导航栏显示状态来判断

https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/ts-basic-components-navigation-V5#onnavbarstatechange9

.onNavBarStateChange((flag) => {
  if (flag) {
    console.log('NavBAR', 'Navigation Index change,now is show')
  } else {
    console.log('NavBAR', 'Navigation Index change,now is hide')
  }
})
1.
2.
3.
4.
5.
6.
7.

2.在根页面可以将pageInfos通过AppStorage存起来,在utils取出来使用

根页面

import navigationLisenerUtils from '../../utils/NavigationLisenerUtils'

pageInfos: NavPathStack = new NavPathStack()
isUseInterception: boolean = false;
aboutToAppear(): void {
  AppStorage.setOrCreate(""pageInfos"",this.pageInfos)
}

Button('use interception', { stateEffect: true, type: ButtonType.Capsule })
  .width('80%')
  .height(40)
  .margin(20)
  .onClick(() => {
    /*this.isUseInterception = !this.isUseInterception;
    if (this.isUseInterception) {
      this.registerInterception();
    } else {
      this.pageInfos.setInterception(undefined);
    }*/
    this.isUseInterception = !this.isUseInterception;
    console.error(""this.isUseInterception:""+this.isUseInterception);
    if (this.isUseInterception) {
      // this.registerInterception();
      navigationLisenerUtils.registerInterception(this.isUseInterception);
      console.error(""action"");
    } else {
      this.pageInfos.setInterception(undefined);
    }
  })
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.

utils

export class NavigationLisenerUtils{
  // isUseInterception: boolean = false;
  registerInterception(isUseInterception: boolean) {
    let pageInfos = AppStorage.get(""pageInfos"") as NavPathStack
    pageInfos.setInterception({
      willShow: (from: NavDestinationContext | ""navBar"", to: NavDestinationContext | ""navBar"",
      operation: NavigationOperation, animated: boolean) => {
        if (!isUseInterception) {
          return;
        }
        if (typeof to === ""string"") {
          console.log(""target page is navigation home"");
          return;
        }
        // redirect target page.Change pageTwo to pageOne.
        let target: NavDestinationContext = to as NavDestinationContext;
        if (target.pathInfo.name === 'pageTwo') {
          target.pathStack.pop();
          target.pathStack.pushPathByName('pageOne', null);
        }
      },
    didShow: (from: NavDestinationContext | ""navBar"", to: NavDestinationContext | ""navBar"",
    operation: NavigationOperation, isAnimated: boolean) => {
      if (!isUseInterception) {
        return;
      }
      if (typeof from === ""string"") {
        console.log(""current transition is from navigation home"");
      } else {
        console.log(`current transition is from  ${(from as NavDestinationContext).pathInfo.name}`)
      }
      if (typeof to === ""string"") {
        console.log(""current transition to is navBar"");
      } else {
        console.log(`current transition is to ${(to as NavDestinationContext).pathInfo.name}`);
      }
      },
      modeChange: (mode: NavigationMode) => {
        if (!isUseInterception) {
          return;
        }
        console.log(`current navigation mode is ${mode}`);
      }
    })
  }
}
let navigationLisenerUtils = new NavigationLisenerUtils()
export default navigationLisenerUtils as NavigationLisenerUtils
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.