Packages

• @ngx-loading-bar/router - Display loading bar when navigating between routes.
• @ngx-loading-bar/http-client - Display the progress of your @angular/common/http requests.
• @ngx-loading-bar/core - Core module to manage the progress bar manually.

Demo

• online demo: https://angular-sypacw.stackblitz.io
• demo-app: Example utilizing all @ngx-loading-bar libraries.

Table of contents

• Getting started
  • 1. Install @ngx-loading-bar
  • 2. Import the installed libraries
  • 3. Include ngx-loading-bar in your app component
• Global config
• Ignoring particular requests
• Manage multi loading bars separately
• Manually manage loading service
• Integration with Material Progress bar
• Credits

Getting started

1. Install @ngx-loading-bar:

  # if you use `@angular/common/http`
  npm install @ngx-loading-bar/core @ngx-loading-bar/http-client --save

  # if you use `@angular/router`
  npm install @ngx-loading-bar/core @ngx-loading-bar/router --save

  # to manage loading-bar manually
  npm install @ngx-loading-bar/core --save

2. Import the installed libraries:

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';

// for HttpClient import:
import { LoadingBarHttpClientModule } from '@ngx-loading-bar/http-client';

// for Router import:
import { LoadingBarRouterModule } from '@ngx-loading-bar/router';

// for Core import:
import { LoadingBarModule } from '@ngx-loading-bar/core';

import { AppComponent } from './app';

@NgModule({
  ...
  imports: [
    ...

    // for HttpClient use:
    LoadingBarHttpClientModule,

    // for Router use:
    LoadingBarRouterModule,

    // for Core use:
    LoadingBarModule
  ],
})
export class AppModule {}

3. Include ngx-loading-bar in your app component:

import { Component } from '@angular/core';

@Component({
  selector: 'app',
  template: `
    ...
    <ngx-loading-bar></ngx-loading-bar>
  `,
})
export class AppComponent {}

Customize ngx-loading-bar

You can pass the following inputs to customize the view:

Global config

The global config can be adjusted by providing a value for LOADING_BAR_CONFIG in your application's root module.

import { LOADING_BAR_CONFIG } from '@ngx-loading-bar/core';

@NgModule({
  providers: [
    providers: [{ provide: LOADING_BAR_CONFIG, useValue: { latencyThreshold: 100 } }],
  ]
})

Ignoring particular requests

The loading bar can also be forced to ignore certain requests, for example, when long-polling or periodically sending debugging information back to the server.

http-client:

Http client doesn't allow passing custom option, in order to achieve that we made a temporary solution (by passing the option throught the header) that will be removed once http-client come with a proper solution.

// ignore a particular $http GET:
httpClient.get('/status', {
  headers: { ignoreLoadingBar: '' },
});

router:

• using the router.navigateByUrl() method:

this.router.navigateByUrl('/custom-path', {
  state: { ignoreLoadingBar: true },
});

• using the routerLink directive:

<a routerLink="/custom-path" [state]="{ ignoreLoadingBar: true }">Go</a>

Manage multi loading bars separately

In some case you may want to differentiate the reason why the loading bar is showing for example show the loading bar when an HttpClient request is being made, and a full page darkening overlay with a spinner when the router is routing to a new page in that case either use ref input or LoadingBarService to control a specific loading bar instance:

• using ref input:

<!-- loading bar for router -->
<ngx-loading-bar ref="router"></ngx-loading-bar>

<!-- loading bar for http -->
<ngx-loading-bar ref="http"></ngx-loading-bar>

• using LoadingBarService service:

// select the router loader instance
const state = this.loader.useRef('router');

// control state
state.start();
state.complete();

// get the progress value
const value$ = state.value$;

Manually manage loading service

1. Import the LoadingBarModule

import { NgModule } from '@angular/core';

import { LoadingBarModule } from '@ngx-loading-bar/core';

@NgModule({
  ...
  imports: [
    ...

    LoadingBarModule,
  ],
})
export class AppModule {}

2. Inject/Use LoadingBarService

import { Component } from '@angular/core';
import { LoadingBarService } from '@ngx-loading-bar/core';

@Component({
  selector: 'app',
  template: `
    ...
    <ngx-loading-bar></ngx-loading-bar>
    <button (click)="loader.start()">start</button>
    <button (click)="loader.complete()">Complete</button>
  `,
})
export class App {
  loader = this.loadingBar.useRef();
  constructor(private loadingBar: LoadingBarService) {}
}

Integration with Material Progress bar

import { Component } from '@angular/core';
import { LoadingBarService } from '@ngx-loading-bar/core';

@Component({
  selector: 'app',
  template: `
    ...
    <mat-progress-bar mode="determinate" [value]="loader.value$ | async"></mat-progress-bar>
  `,
})
export class App {
  constructor(public loader: LoadingBarService) {}
}

Lazy Loading modules

If you're using Lazy Loaded Modules in your app, please use LoadingBarRouterModule, because although a request is being fired in the nework console to fetch your lazy load module.js file, it won't trigger the LoadingBarHttpClientModule.

Credits

• angular-loading-bar
• https://github.com/sir-valentin/Angular2LoadingBar.git