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Angular 7 :Error with Angular routing **'router-outlet'** is not a known element: [duplicate]

This question already has answers here:
'router-outlet' is not a known element
(24 answers)
Closed 8 months ago.
I have tried to include all imports to the necessary files,But I have got the following error while compiling. How could I solve it?
I have generated four differnet commonents Menu,home,contact,and about.Additional to this thare are also Header component that will later help to contain the memu bar to switch between the differnt components.And also footer component.The app-routing.ts and routes.ts files are also attached with this file,which helps for routing purpose.
'router-outlet' is not a known element:
1. If 'router-outlet' is an Angular component, then verify that it is part of this module.
2. If 'router-outlet' is a Web Component then add 'CUSTOM_ELEMENTS_SCHEMA' to the
'#NgModule.schemas' of this component to suppress this message. ("<app-header></app-header>
[ERROR ->]<router-outlet></router-outlet>
<app-footer></app-footer>"): ng:///AppModule/AppComponent.html#1:0
at syntaxError (compiler.js:1021)
at TemplateParser.push../node_modules/#angular/compiler/fesm5 /compiler.js.TemplateParser.parse (compiler.js:14830)
at JitCompiler.push../node_modules/#angular/compiler/fesm5/compiler.js.JitCompiler._parseTemplate (compiler.js:24018)
at JitCompiler.push../node_modules/#angular/compiler/fesm5/compiler.js.JitCompiler._compileTemplate (compiler.js:24005)
at compiler.js:23948
at Set.forEach (<anonymous>)
at JitCompiler.push../node_modules/#angular/compiler/fesm5/compiler.js.JitCompiler._compileComponents (compiler.js:23948)
at compiler.js:23858
at Object.then (compiler.js:1012)
at JitCompiler.push../node_modules/#angular/compiler/fesm5/compiler.js.JitCompiler._compileModuleAndComponents (compiler.js:23857)
routes.ts file
import { Routes } from '#angular/router';
import { MenuComponent } from '../menu/menu.component';
import { DishdetailComponent } from '../dishdetail/dishdetail.component';
import { HomeComponent } from '../home/home.component';
import { AboutComponent } from '../about/about.component';
import { ContactComponent } from '../contact/contact.component';
export const routes: Routes = [
{ path: 'home', component: HomeComponent },
{ path: 'menu', component: MenuComponent },
{ path: '', redirectTo: '/home', pathMatch: 'full' }
];
app-routing.module.ts file
import { NgModule } from '#angular/core';
import { CommonModule } from '#angular/common';
import { RouterModule, Routes } from '#angular/router';
import { routes } from './routes';
#NgModule({
imports: [
CommonModule,
RouterModule.forRoot(routes)
],
exports: [ RouterModule ],
declarations: []
})
export class AppRoutingModule { }
app.module.ts file
import { BrowserModule } from '#angular/platform-browser';
import { NgModule } from '#angular/core';
import { BrowserAnimationsModule } from '#angular/platform-browser/animations';
import { MatToolbarModule } from '#angular/material/toolbar';
import {MatListModule} from '#angular/material/list';
import {MatGridListModule} from '#angular/material/grid-list';
import {MatCardModule} from "#angular/material/card";
import {MatButtonModule} from "#angular/material/Button";
import { FlexLayoutModule } from '#angular/flex-layout';
import 'hammerjs';
import { AppComponent } from './app.component';
import { MenuComponent } from './menu/menu.component';
import { FooterComponent} from './footer/footer.component';
import { HeaderComponent} from './header/header.component';
import { DishdetailComponent } from './dishdetail/dishdetail.component';
import { HomeComponent } from './home/home.component'
import { AboutComponent } from './about/about.component';
import { ContactComponent } from './contact/contact.component';
import {DishService} from './services/dish.service';
import {RouterModule} from '#angular/router';
import { AppRoutingModule } from './app-routing/app-routing.module';
#NgModule({
declarations: [
AppComponent,
MenuComponent,
DishdetailComponent,
HeaderComponent,
FooterComponent,
HomeComponent,
AboutComponent,
ContactComponent
],
imports: [
BrowserModule,
BrowserAnimationsModule,
FlexLayoutModule,
MatToolbarModule,
MatGridListModule,
MatCardModule,
MatButtonModule,
MatListModule,
AppRoutingModule,
RouterModule
],`
`providers: [
DishService
],`
`bootstrap: [AppComponent]`
`})`
export class AppModule { }
app.component.html file
<app-header></app-header>
<router-outlet></router-outlet>
<app-footer></app-footer>

I see you are missing app-routing.module.ts inside the imports of AppModule
#NgModule({
imports: [
CommonModule,
routingModule
],
})
export class AppModule{ }

I noticed that in your app.module.ts file you have back ticks ``` in inappropriate places somewhere around providers & bootstrap array. I copied & pasted this from your own code so you can see it better:
...MatListModule,
AppRoutingModule,
RouterModule
],`
`providers: [
DishService
],`
`bootstrap: [AppComponent]`
`})`
export class AppModule { }
Do this:
Remove all the back ticks in the app.module.ts file like I have done below and restart your terminal. This should solve any problems you are having.
...MatListModule,
AppRoutingModule,
RouterModule
],
providers: [
DishService
],
bootstrap: [AppComponent]
})
export class AppModule { }
I copied and pasted your code and worked on the files you provided information about. With the back ticks removed, your code works fine here on my laptop. Here's the result in the gif below, route works properly & no errors in the console. Example with just home & menu components.
Final result:
I removed all other things that didn't relate to routing from your code so that it would be easier to detect errors. Here's my folder structure.
Folder structure:
And here are the contents of my files:
route.ts file:
import { Routes } from '#angular/router';
import { MenuComponent } from './menu/menu.component';
import { HomeComponent } from './menu/home.component';
export const routes: Routes = [
{ path: 'home', component: HomeComponent },
{ path: 'menu', component: MenuComponent },
{ path: '', redirectTo: '/home', pathMatch: 'full' }
];
app.module.ts file:
import { BrowserModule } from '#angular/platform-browser';
import { NgModule } from '#angular/core';
import { AppComponent } from './app.component';
import { MenuComponent } from './menu/menu.component';
import { HomeComponent } from './menu/home.component';
import { AppRoutingModule } from './app-routing.module';
import { RouterModule } from '#angular/router';
#NgModule({
declarations: [
AppComponent,
HomeComponent,
MenuComponent
],
imports: [
BrowserModule,
AppRoutingModule,
RouterModule
],
providers: [
],
bootstrap: [AppComponent]
})
export class AppModule { }
app.component.ts file:
import { Component } from '#angular/core';
#Component({
selector: 'app-root',
template: `
<router-outlet></router-outlet>
`
})
export class AppComponent {
}
app-routing.module.ts:
import { NgModule } from '#angular/core';
import { CommonModule } from '#angular/common';
import { RouterModule, Routes } from '#angular/router';
import { routes } from './routes';
#NgModule({
imports: [
CommonModule,
RouterModule.forRoot(routes)
],
exports: [ RouterModule ],
declarations: []
})
export class AppRoutingModule { }
menu.component.ts:
import { Component } from '#angular/core';
#Component({
template: '<h1>Menu Component</h1>'
})
export class MenuComponent {
}
home.component.ts:
import { Component } from '#angular/core';
#Component({
template: '<h1>Home Component</h1>'
})
export class HomeComponent {
}
Like I said, once I removed those unnecessary back ticks from the app.module.ts, your code worked fined with no errors.

I have started everything from scratch.Then my issue was fixed.I don't exactly know where is my problem.But,probably I have made routes file in separate folder.Making routes file in app-routing folder, fixed my issue.

Getting 'ngbCollapse' since it isn't a known property of 'div'. error after moving components into sub module

Error
compiler.js:215 Uncaught Error: Template parse errors:
Can't bind to 'ngbCollapse' since it isn't a known property of 'div'. ("][ngbCollapse]="isHidden">
I have a NavbarComponent and a FooterComponent that I want to move into the SharedModule, to keep the root app.module cleaner.
app.module
import { AdminComponent } from './admin/admin.component';
// import { NavbarComponent } from './navbar/navbar.component';
// import { FooterComponent } from './footer/footer.component';
// Modules
import { DashboardModule } from './dashboard/dashboard.module';
import { HomeModule } from './home/home.module';
#NgModule({
declarations: [
AppComponent,
LoginComponent,
RegisterComponent,
PasswordResetComponent,
ResetPasswordComponent,
AdminComponent,
// NavbarComponent,
// FooterComponent,
share.module
However, once I moved those components into here, and update their paths correctly ./ -> ../ the app breaks.
import { NgModule } from '#angular/core';
import { CommonModule } from '#angular/common';
import { NavbarComponent } from '../navbar/navbar.component';
import { FooterComponent } from '../footer/footer.component';
import { TermsComponent } from './terms.component';
import { PageNotFoundComponent } from './not-found.component';
import { PrivacyPolicyComponent } from './privacy-policy.component';
#NgModule({
imports: [
CommonModule
],
declarations: [
NavbarComponent,
FooterComponent,
TermsComponent,
PageNotFoundComponent,
PrivacyPolicyComponent
]
})
export class SharedModule { }
navbar.component.ts
import { Component, OnInit } from '#angular/core';
import { AuthService } from '../auth.service';
import { environment } from '../../environments/environment';
#Component({
selector: 'app-navbar',
templateUrl: './navbar.component.html',
styleUrls: ['./navbar.component.scss']
})
export class NavbarComponent implements OnInit {
isHidden = true;
oauthUrl = this.authService.generateOauthUrl();
constructor(public authService: AuthService) { }
ngOnInit() {
}
logout() {
sessionStorage.clear();
}
}
Then a couple of lines with the [ngbCollapse] in navbar.component.html
<div *ngIf="!authService.isLoggedIn()" class="collapse navbar-collapse" id="navbarSupportedContent" [ngbCollapse]="isHidden">
I think this has something to do with the relative paths, any ideas?

To use ng-bootstrap components and directives in Angular templates, you need to import the NgbModule. In your case, you should import it in the SharedModule. Also, in order to use the shared components in other parts of the application, you should export them from the SharedModule and import the SharedModule in the modules when the components are to be used.
shared.module.ts
...
import { NgbModule } from '#ng-bootstrap/ng-bootstrap';
#NgModule({
imports: [
CommonModule,
NgbModule
],
declarations: [
NavbarComponent,
FooterComponent,
TermsComponent,
PageNotFoundComponent,
PrivacyPolicyComponent
],
exports: [
NavbarComponent,
FooterComponent,
TermsComponent,
PageNotFoundComponent,
PrivacyPolicyComponent
]
})
export class SharedModule { }
app.module.ts
import { SharedModule } from './shared/shared.module';
...
#NgModule({
imports: [
SharedModule,
...
],
...
})
Note: if you want to use ng-bootstrap components and directives in templates outside of the SharedModule, you should add NgbModule to the exports of the SharedModule.

To work with ng-bootsrap you should add this dependency first :
ng add #ng-bootstrap/ng-bootstrap
source: https://ng-bootstrap.github.io/#/home
then imporst the module as follows :
import { NgbModule } from '#ng-bootstrap/ng-bootstrap';
#NgModule({
imports: [
CommonModule,
NgbModule
],
...

How to import custom modules in Angular 4?

I am trying to use one of the custom modules I have built and put it in another module
custom modules:
my-test.module.ts
import { NgModule } from '#angular/core';
import { CommonModule } from '#angular/common';
import { MyTestComponent } from './my-test.component';
#NgModule({
declarations: [
MyTestComponent
],
imports: [
CommonModule,
],
exports: [ MyTestComponent]
})
export class MyTestModule { }
Another module that I need to pull in
my-parent.module.ts
import {CommonModule} from '#angular/common';
import {NgModule} from '#angular/core';
import { MyParentComponent } from './my-parent.component';
import { MyTestModule } from '../my-test/my-test.module';
#NgModule({
'imports': [
CommonModule,
MyTestModule
],
'declarations': [
MyParentComponent
],
'exports': [
MyParentComponent
]
})
export class MyParentModule {}
my-parent.component.ts
import { Component, Inject, Injectable, OnInit } from '#angular/core';
import { MyTestComponent } from '../my-test/my-test.component'
#Component({
'selector': 'my-parent',
'template': `
test
`
})
#Injectable()
export class MyParentComponent implements OnInit {
public myTestComponent: MyTestComponent;
constructor() {}
ngOnInit() {
console.log(this.myTestComponent) <----show undefined here.
}
}
I am not sure how to import the my-test component into my-parent component.
What am I doing wrong? Thanks a lot!
Update
Slightly change my codes above to fit my case. It initial a MytestComponent in the beginning and this.myTestComponent shows undefined.

1- in my-parent.component.html add <test component selector> </ test component selector #test>
2- in the parent ts file add :
#ViewChild('test') test: MyTestComponent;
then you will be able to access all the methods and parameters in MyTestComponent

Angular2 (CLI): separate common components and logic-components

In angular 1.4 i was using ng6 boilerplate and it was generating an awesome structure, like:
app
common
components
services
etc...
Now i'm trying to learn angular2 with typescript. I'm using Angular CLI.
And i wanna port some of structure from angular 1.4: i mean to separate, for example, select-component from customer-component etc.
And i created such structure:
components - is a module, customer is a module, list - is a component.
How in my app.component.html i can use list-component? Like:
<app-customer-list></app-customer-list>
I have troubles with importing modules & components.
I do it in a such way:
**app.module.ts**
import { BrowserModule } from '#angular/platform-browser';
import { NgModule } from '#angular/core';
import { FormsModule } from '#angular/forms';
import { HttpModule } from '#angular/http';
import { AppComponent } from './app.component';
import { ComponentsModule } from './components/components.module';
#NgModule({
declarations: [
AppComponent
],
imports: [
BrowserModule,
FormsModule,
HttpModule,
ComponentsModule
],
providers: [],
bootstrap: [AppComponent]
})
export class AppModule { }
--
**components.module.ts**
import { NgModule } from '#angular/core';
import { CustomerModule } from './customer/customer.module';
#NgModule({
imports: [
CustomerModule
],
declarations: []
})
export class ComponentsModule { }
--
**customer.module.ts**
import { NgModule } from '#angular/core';
import { CommonModule } from '#angular/common';
import { CustomerComponent } from './customer.component';
import { ListComponent } from './list/list.component';
#NgModule({
imports: [
CommonModule
]
declarations: [CustomerComponent, ListComponent]
})
export class CustomerModule { }
--
**list.component.ts**
import { Component, OnInit } from '#angular/core';
#Component({
selector: 'app-customer-list',
templateUrl: './list.component.html',
styleUrls: ['./list.component.css']
})
export class ListComponent implements OnInit {
constructor() { }
ngOnInit() {
}
}
What i do wrong? How can i correctly import them?

You are forgetting to export your components/modules in those modules that you are sharing with other modules:
**customer.module.ts**
import { NgModule } from '#angular/core';
import { CommonModule } from '#angular/common';
import { CustomerComponent } from './customer.component';
import { ListComponent } from './list/list.component';
#NgModule({
imports: [
CommonModule
]
declarations: [CustomerComponent, ListComponent],
exports: [CustomerComponent, ListComponent]
})
export class CustomerModule { }
**components.module.ts**
import { NgModule } from '#angular/core';
import { CustomerModule } from './customer/customer.module';
#NgModule({
imports: [
CustomerModule
],
exports: [CustomerModule]
declarations: []
})

AngularJS 2 calling a directive inside another one

I'm trying to follow the angualrJS 2.0 tutorial on calling another component inside another one. However I'm getting an error saying that it is not a known element on the <main-footer></main-footer> selector. What am i doing wrong?
//app.component.ts
import { Component } from '#angular/core';
import { ROUTER_DIRECTIVES } from '#angular/router';
import { FooterComponent } from './footer.component';
#Component({
selector: 'my-app',
// use templateurl for template files
template: `
<h1>My First Angular App 22</h1>
<main-footer></main-footer>
`,
directives: [FooterComponent]
})
export class AppComponent {
}
// footer.component.ts
import { Component } from '#angular/core';
#Component({
selector: 'main-footer',
template: `
<h2>The footer</h2>
`,
})
export class FooterComponent{
}
EDIT
So I got it working, by declaring and importing the file in app.module.ts as well as the app.component.ts file Thanks to the help from #Chang I did not see this in the tutorials on AngualrJS 2.0
// app.module.ts
import { NgModule } from '#angular/core';
import { BrowserModule } from '#angular/platform-browser';
import { AppComponent } from './app.component';
import { FooterComponent } from './footer.component';
#NgModule({
imports: [ BrowserModule ],
declarations: [ AppComponent, FooterComponent],
bootstrap: [ AppComponent ]
})
export class AppModule { }

can try to declare "FooterComponent" in your app.modules ?
#NgModule({
imports: [
BrowserModule,
FormsModule,
HttpModule,
InMemoryWebApiModule.forRoot(InMemoryDataService),
routing
],
declarations: [
AppComponent,
FooterComponent
],
providers: [
],
bootstrap: [ AppComponent ]
})
export class AppModule {
}