I'm currently working with the latest Ionic and I'm having a hard time trying to get a CLI generates component to work.
I start with a blank proyect and then create a new component with:
ionic generate component my-component
The command runs fine and creates the following files:
CREATE src/app/my-component/my-component.component.html (31 bytes)
CREATE src/app/my-component/my-component.component.spec.ts (664 bytes)
CREATE src/app/my-component/my-component.component.ts (293 bytes)
CREATE src/app/my-component/my-component.component.scss (0 bytes)
Then I proceed to use the new component in my main page like this:
<ion-content padding>
<my-component></my-component>
</ion-content>
The app.module.ts file is updated like this:
import { NgModule } from '#angular/core';
import { BrowserModule } from '#angular/platform-browser';
import { RouterModule, RouteReuseStrategy, Routes } from '#angular/router';
import { IonicModule, IonicRouteStrategy } from '#ionic/angular';
import { SplashScreen } from '#ionic-native/splash-screen/ngx';
import { StatusBar } from '#ionic-native/status-bar/ngx';
import { AppComponent } from './app.component';
import { AppRoutingModule } from './app-routing.module';
import { MyComponentComponent } from './my-component/my-component.component';
#NgModule({
declarations: [AppComponent, MyComponentComponent],
entryComponents: [],
imports: [BrowserModule, IonicModule.forRoot(), AppRoutingModule],
providers: [
StatusBar,
SplashScreen,
{ provide: RouteReuseStrategy, useClass: IonicRouteStrategy }
],
bootstrap: [AppComponent]
})
export class AppModule {}
When running the app in ionic lab I get the followin error:
ERROR Error: Uncaught (in promise): Error: Template parse errors:
'my-component' is not a known element
This is my system info:
ionic (Ionic CLI) : 4.2.1
Ionic Framework : #ionic/angular 4.0.0-beta.12
#angular-devkit/build-angular : 0.7.5
#angular-devkit/schematics : 0.7.5
#angular/cli : 6.1.5
#ionic/angular-toolkit : 1.0.0
Any ideas why is this happening? I worked before with Ionic 3 and never get this problem.
update:
This is my default my-component.component.ts file:
import { Component, OnInit } from '#angular/core';
#Component({
selector: 'app-my-component',
templateUrl: './my-component.component.html',
styleUrls: ['./my-component.component.scss']
})
export class MyComponentComponent implements OnInit {
constructor() { }
ngOnInit() {
}
}
In order to use a custom component inside another component you have to include it in exports array.
#NgModule({
....
declarations: [AppComponent, MyComponentComponent],
entryComponents: [],
exports:[MyComponentComponent]
....
})
export class AppModule {}
You can either do this way or you can make all your custom components inside another customModule and then import that module in app.component.ts page.
The name you are referring to the component is wrong. selector for your MyComponentComponent class is app-my-component, so you have to use <app-my-component></app-my-component> instead of <my-component></my-component>.
Related
This is my standalone component
import { Component } from '#angular/core';
import { CommonModule } from '#angular/common';
#Component({
selector: 'app-navbar',
standalone: true,
imports: [CommonModule],
templateUrl: './navbar.component.html',
styleUrls: ['./navbar.component.scss']
})
export class NavbarComponent {
}
and this is where i have imported it (in admin module)
import { NgModule } from '#angular/core';
import { CommonModule } from '#angular/common';
import { AdminRoutingModule } from './admin-routing.module';
import { UsersComponent } from './users/users.component';
import { NavbarComponent } from '../components/navbar/navbar.component';
#NgModule({
declarations: [
UsersComponent
],
imports: [
CommonModule,
AdminRoutingModule,
NavbarComponent,
]
})
export class AdminModule { }
In my usercomponent.html template i did
<p>users works!</p>
<app-navbar></app-navbar>
When I run ng serve I got
`error NG8001: 'app-navbar' is not a known element:
If 'app-navbar' is an Angular component, then verify that it is part of this module.
If 'app-navbar' is a Web Component then add 'CUSTOM_ELEMENTS_SCHEMA' to the '#NgModule.schemas' of this component to suppress this message.
2 `
I would like to know why I have this error and how to fix it
Thanks !
If NavbarComponent is part of another module, on that module you have to export the component using exports[], and then import the module, not the component on AdminModule.
If it is not part of other module, you have to include the component on declarations[] not on imports[].
I have created my own angular element to use as a web component in a different single html page.
When I run it as a normal component using ng serve the app works properly. However, when I create the element and use it in a different page the app stops working as it should. The css seems wrong and there is a lot of bugs.
My AppModule:
import { Injector, NgModule, DoBootstrap } from '#angular/core';
import { createCustomElement } from '#angular/elements';
import { BrowserModule } from '#angular/platform-browser';
import { DrawBoardComponent } from './draw-board/draw-board.component';
import {MatExpansionModule} from '#angular/material/expansion';
import { BrowserAnimationsModule } from '#angular/platform-browser/animations';
#NgModule({
declarations: [
DrawBoardComponent
],
imports: [
BrowserAnimationsModule,
BrowserModule,
MatExpansionModule
],
entryComponents: [DrawBoardComponent]
})
export class AppModule implements DoBootstrap {
constructor(private injector: Injector) {}
ngDoBootstrap() {
const element = createCustomElement(DrawBoardComponent, {injector: this.injector});
customElements.define('app-draw', element);
}
}
I used concat to make a single js file from the js files created when ng build.
It is first time To use Angular Now I'm learning angular 7:
- I create a new custom component in
- |src folder
---| app
----|| server (name of my component)
then I added in app.component.html the name of component
I see in the tutorial show in browser
the server component
even if he add it empty element
I do all steps in
server.component.ts file
import { Component } from '#angular/core';
#Component({
selector:'app-server',
templateUrl: './server.component.html'
})
export class ServerComponent {
}
& app.module.ts file
import { BrowserModule } from '#angular/platform-browser';
import { NgModule } from '#angular/core';
import { AppComponent } from './app.component';
import { ServerComponent } from './server/server.component';
#NgModule({
declarations: [
AppComponent,
ServerComponent
],
imports: [
BrowserModule
],
providers: [],
bootstrap: [AppComponent]
})
export class AppModule { }
Have you define your <app-server></app-server> somewhere?
For instance in the app.component.html
<app-navbar></app-navbar>
<app-server></app-server>
<app-footer></app-footer>
Also you will find an example here : https://angular.io/tutorial/toh-pt1
In your app.component.html add :
<app-server></app-server>
Thus you'll see its HTML.
What you did is in fact kind of import it and make it visible to other components declared in AppModule, but you didnt call it actually.
In my Angular2 app am getting the following error Error: (SystemJS) Unexpected value 'ReleasesService' declared by the module 'AppModule'. Please add a #Pipe/#Directive/#Component annotation.
My AppModule:
import { NgModule } from '#angular/core';
import { BrowserModule } from '#angular/platform-browser';
import { routing } from './app.routes';
import { HttpModule } from '#angular/http';
import { SearchFilter } from '../app/search-filter.pipe';
import { ReleasesService } from '../app/releases/releases.service';
import { AppComponent } from './app.component';
import { HomeComponent } from '../app/home/home.component';
import { ReleasesComponent } from '../app/releases/releases.component';
import { DistroComponent } from '../app/distro/distro.component';
import { ContactComponent } from '../app/contact/contact.component';
#NgModule({
imports: [ BrowserModule, HttpModule, routing ],
declarations: [ AppComponent,
SearchFilter,
HomeComponent,
ReleasesComponent,
ReleasesService,
DistroComponent,
ContactComponent ],
bootstrap: [ AppComponent ]
})
export class AppModule { }
My ReleasesService:
import { Injectable } from '#angular/core';
import { Http, Response } from '#angular/http';
import { Observable } from 'rxjs/Observable';
import { IRelease } from './release';
import 'rxjs/add/operator/map';
#Injectable()
export class ReleasesService {
getReleases() {
return IRelease;
}
}
How to fix it? I reinstalled the Quickstarter (the base for my App), and having the same error when try to create the service.
declarations is only for declarable classes: Components Directives and Pipes
You can add ReleasesService to providers array
#NgModule({
imports: [ BrowserModule ],
declarations: [ AppComponent ],
providers: [ ReleasesService ],
bootstrap: [ AppComponent ]
})
export class AppModule { }
See also
https://angular.io/guide/ngmodule-faq#what-classes-should-i-add-to-declarations
I had a similar problem, occurring while a project had angular2 as dependency and a project dependency (with the failing component) as well. Seems like angular2 metadata gets attached to the direct angular2 dependency, so the component in the project dependency wasn't declared in the angular2 of the project.
Workaround is to remove angular2 from the dependency (declaring it as devDependency there) and only use one angular2 instance.
Be sure the decorator has the caracter #.
If you don´t type # before the decorator function you will have this error message
#Component({ selector: '...', }) -> Correct
Component({ selector: '...', }) -> ERROR MESAGE: 'add a #Pipe/#Directive/#component'
I have an app module and single component application (made to demonstrate my problem), and getting following error:
Error in ./AppComponent class AppComponent_Host - inline template:0:0 caused by: No provider for UserService! ; Zone: <root> ; Task: Promise.then ; Value:
code for AppModule:
import { NgModule } from '#angular/core';
import { BrowserModule } from '#angular/platform-browser';
import { UserService } from './components/common/userservice';
#NgModule({
imports: [
BrowserModule,
],
declarations: [
AppComponent
],
providers: [UserService],
bootstrap: [AppComponent],
entryComponents: []
})
export class AppModule {
}
Code for my AppComponent:
import { Component} from '#angular/core';
import { UserService} from './userservice';
#Component({
selector: 'App',
template: `<h3>App component</h3>
user name: {{userName}}
`,
providers: []
})
export class AppComponent {
userName: string;
constructor(userService: UserService) {
this.userName = userService.userName;
}
}
My UserService Code:
import { Injectable, EventEmitter } from '#angular/core';
#Injectable()
export class UserService {
obs$: EventEmitter<any> = new EventEmitter<any>()
userName = 'Sherlock Holmes';
}
Now if i add UserService as provider to AppComponent, it will solve the issue. but i dont want to, because i want only one instance of my service in whole application. Even in subModules(feature modules).
according to my understanding, if i add service as provider on module level, then i can just inject it to any component under module.
here is am example i was watching.
Plunker
am using angular2 version: "2.0.0"
The import path is wrong: you use /Common in one and /common right below.
Visual Studio and WebStorm will not show IntelliSense errors for case-sensitivity of paths.
Furthermore, if using Angular 5's AoT template compilation, you can get a "This component is not part of a module" error, even though it is, because the import path is incorrect. Without AoT this will work, so you'll get a surprise when converting to AoT.
Remove your service: UserService from app.module.ts, then add in component:
#Component({
selector: 'App',
template: `<h3>App component</h3>
user name: {{userName}}
`,
providers: [UserService]
})
Hope this will help you.
An additional reason for getting this error - I duplicated a service to a different directory and was updating each file individually. Even though the first file still existed I got this error until I updated app.module.ts.