Angular Cannot reattach ActivatedRouteSnapshot with a different number of children

问题

Here is my routing in a nativescript-angular project:

const routes: Routes = [

    {
        path: "",
        redirectTo: "/tabs/default",
        pathMatch: "full"
    },
    {
        path: "tabs",
        loadChildren: "~/app/modules/tabs/tabs.module#TabsModule"
    },
    {
        path: "login",
        loadChildren: "~/app/modules/login/login.module#LoginModule"
    },
    {
        path: "register",
        loadChildren: "~/app/modules/register/register.module#RegisterModule"
    }

];

@NgModule({
    imports: [NativeScriptRouterModule.forRoot(routes, {
        preloadingStrategy: PreloadAllModules
    })],
    exports: [NativeScriptRouterModule]
})

The scenario which leads to the error: First the app starts with tabs route, then I go to the login page, after that I go to register and then again I go to tabs page (and clean the history). After that if I go to login page again and get back to previous one (tabs page), the error occurs.

The error:

JS: Error: Cannot reattach ActivatedRouteSnapshot with a different number of children
JS:     at setFutureSnapshotsOfActivatedRoutes (file:///data/data/org.nativescript.tns57/files/app/tns_modules/@angular/router/bundles/router.umd.js:1950:19) [angular]
JS:     at setFutureSnapshotsOfActivatedRoutes (file:///data/data/org.nativescript.tns57/files/app/tns_modules/@angular/router/bundles/router.umd.js:1954:13) [angular]
JS:     at createNode (file:///data/data/org.nativescript.tns57/files/app/tns_modules/@angular/router/bundles/router.umd.js:1935:17) [angular]
JS:     at file:///data/data/org.nativescript.tns57/files/app/tns_modules/@angular/router/bundles/router.umd.js:1975:20 [angular]
JS:     at Array.map (<anonymous>) [angular]
JS:     at createOrReuseChildren (file:///data/data/org.nativescript.tns57/files/app/tns_modules/@angular/router/bundles/router.umd.js:1958:30) [angular]
JS:     at createNode (file:///data/data/org...

Any idea?

回答1:

Try change the first route

{
    path: "",
    redirectTo: "tabs",
    pathMatch: "full"
}

and set your TabsModule like that

const routes: Routes = [    
    {
        path: "",
        redirectTo: "default",
        pathMatch: "full"
    },
    {
        path: "default",
        component: YourDefaultComponent
    }
    ...
];

UPDATE : If you get an same error, you can use AttachDetachReuseStrategy

import { ActivatedRouteSnapshot, RouteReuseStrategy, DetachedRouteHandle } from '@angular/router';

interface RouteStorageObject {
    snapshot: ActivatedRouteSnapshot;
    handle: DetachedRouteHandle;
}

export class CustomReuseStrategy implements RouteReuseStrategy {


    handlers: { [key: string]: RouteStorageObject } = {};

    retrieve(route: ActivatedRouteSnapshot): DetachedRouteHandle {
        if (!route.routeConfig) return null;
        if (route.routeConfig.loadChildren) return null;
        return this.handlers[route.routeConfig.path];
    }

    .....

}

then I make shouldDetach function also check for loadChildren to prevent RouteReuseStrategy save wrong ActivatedRouteSnapshot:

shouldDetach(route: ActivatedRouteSnapshot): boolean {
    if (!route.routeConfig || route.routeConfig.loadChildren) {
        return false;
    }
    return true;
}

Ofcourse, modify your AppModule

@NgModule({
    imports: [...],
    providers: [
        {provide: RouteReuseStrategy, useClass: CustomReuseStrategy}
    ],
    ....
)}
export class AppModule {
}

回答2:

Try updating to nativescript-angular to version 7.2.4 . The repo link that you posted is using version 7.2.3 that contains some issue with routing.

https://github.com/NativeScript/nativescript-angular/pull/1740

来源：https://stackoverflow.com/questions/56218581/angular-cannot-reattach-activatedroutesnapshot-with-a-different-number-of-childr

标签

angular

angular-router

nativescript-angular