Add network status component.

- Tracks status uof user's network connection.

src/app/shared/network-status/network-status.component.html

@@ -0,0 +1,13 @@
+<nav class="navbar navbar-dark bg-dark">
+  <h1 class="navbar-brand">
+    <div *ngIf="noInternetConnection; then offlineBlock else onlineBlock"></div>
+    <ng-template #offlineBlock>
+      <strong style="color: red;">OFFLINE </strong>
+      <img width="20rem" src="assets/images/no-wifi.svg" alt="Internet Disconnected">
+    </ng-template>
+    <ng-template #onlineBlock>
+      <strong style="color: lawngreen;">ONLINE </strong>
+      <img width="20rem" src="assets/images/wifi.svg" alt="Internet Connected">
+    </ng-template>
+  </h1>
+</nav>

src/app/shared/network-status/network-status.component.spec.ts

@@ -0,0 +1,25 @@
+import { ComponentFixture, TestBed } from '@angular/core/testing';
+
+import { NetworkStatusComponent } from './network-status.component';
+
+describe('NetworkStatusComponent', () => {
+  let component: NetworkStatusComponent;
+  let fixture: ComponentFixture<NetworkStatusComponent>;
+
+  beforeEach(async () => {
+    await TestBed.configureTestingModule({
+      declarations: [ NetworkStatusComponent ]
+    })
+    .compileComponents();
+  });
+
+  beforeEach(() => {
+    fixture = TestBed.createComponent(NetworkStatusComponent);
+    component = fixture.componentInstance;
+    fixture.detectChanges();
+  });
+
+  it('should create', () => {
+    expect(component).toBeTruthy();
+  });
+});

src/app/shared/network-status/network-status.component.ts

@@ -0,0 +1,30 @@
+import {Component, OnInit, ChangeDetectionStrategy, ChangeDetectorRef} from '@angular/core';
+
+@Component({
+  selector: 'app-network-status',
+  templateUrl: './network-status.component.html',
+  styleUrls: ['./network-status.component.scss'],
+  changeDetection: ChangeDetectionStrategy.OnPush
+})
+export class NetworkStatusComponent implements OnInit {
+  noInternetConnection: boolean = !navigator.onLine;
+
+  constructor(
+    private cdr: ChangeDetectorRef,
+  ) {
+    this.handleNetworkChange();
+  }
+
+  ngOnInit(): void {
+  }
+
+  handleNetworkChange(): void {
+    setTimeout(() => {
+      if (!navigator.onLine !== this.noInternetConnection) {
+        this.noInternetConnection = !navigator.onLine;
+        this.cdr.detectChanges();
+      }
+      this.handleNetworkChange();
+    }, 5000);
+  }
+}

src/app/shared/shared.module.ts

@@ -10,6 +10,7 @@ import {MatIconModule} from '@angular/material/icon';
 import {TokenRatioPipe} from '@app/shared/_pipes/token-ratio.pipe';
 import { ErrorDialogComponent } from './error-dialog/error-dialog.component';
 import {MatDialogModule} from '@angular/material/dialog';
+import { NetworkStatusComponent } from './network-status/network-status.component';
 
 
 
@@ -21,15 +22,17 @@ import {MatDialogModule} from '@angular/material/dialog';
     MenuSelectionDirective,
     MenuToggleDirective,
     TokenRatioPipe,
-    ErrorDialogComponent
-  ],
-  exports: [
-    TopbarComponent,
-    FooterComponent,
-    SidebarComponent,
-    MenuSelectionDirective,
-    TokenRatioPipe
+    ErrorDialogComponent,
+    NetworkStatusComponent
   ],
+    exports: [
+        TopbarComponent,
+        FooterComponent,
+        SidebarComponent,
+        MenuSelectionDirective,
+        TokenRatioPipe,
+        NetworkStatusComponent
+    ],
   imports: [
     CommonModule,
     RouterModule,