在Angular中动态更改/还原页面标题

Question

So I have managed to get the page location which i then paste in a h1 in my header component. I have also managed that when one hovers over the navigation items, the header h1 changes dynamically to the text that is being hovered:

Here comes my problem: on mouseout, that is when I am not hovering on a navigation item I need the title to revert back to the the page location that was initially rendered:

Example: I am at localhost:4200/about, the header shows "about"! I hover over a navigation item "contact", the header shows "contact", now when i move the mouse away from contact i need the header title back to location that is "about".

I have tried a solution with input, output and event emmiters passing the text between child and parent a lot of times, apart from that not ending up working, its seems to complication of a solution for something so small.

Below is my nav-component.html

 <nav class="nav-menu {{ menuStatus }}" (click)="closeNav($event)"> <ul> <li> <a routerLink="/about" (mouseover)="getText($event)" (click)="closeNav($event)">about</a> </li> <li> <a routerLink="/what-to-expect" (mouseover)="getText($event)" (click)="closeNav($event)">what to expect</a> </li> <li> <a routerLink="/gallery" (mouseover)="getText($event)" (click)="closeNav($event)">gallery</a> </li> <li> <a routerLink="/activities" (mouseover)="getText($event)" (click)="closeNav($event)">activities</a> </li> <li> <a routerLink="/contact" (mouseover)="getText($event)" (click)="closeNav($event)">contact</a> </li> </ul> </nav> 

nav-component.ts

 import { Component, OnInit, Input, EventEmitter, Output } from '@angular/core'; @Component({ selector: 'app-nav', templateUrl: './nav.component.html', styleUrls: ['./nav.component.scss'] }) export class NavComponent implements OnInit { title: string; navClose: boolean; @Output() sendTitle = new EventEmitter < string > (); @Output() closingNav = new EventEmitter < string > (); @Input() menuStatus: string; constructor() {} ngOnInit() {} getText($event) { this.title = event.target.innerText; this.sendTitle.emit(this.title) } closeNav($event) { this.navClose = false; this.closingNav.emit(this.navClose); } } 

header-component.html

 <header> <div class="header-left"> <h1>{{pageTitle}}</h1> </div> <div class="header-right"> <app-burger (opened)="burgerStatus($event)" [burgerClose]="navStatus"></app-burger> </div> </header> <app-nav (sendTitle)="getTitle($event)" [menuStatus]="burger" (closingNav)="getNavStatus($event)"></app-nav> 

header-component-ts

 import { Component, OnInit } from '@angular/core'; import { BurgerComponent } from './burger/burger.component'; import { Location } from "@angular/common"; import { Router } from "@angular/router"; @Component({ selector: 'app-header-component', templateUrl: './header-component.component.html', styleUrls: ['./header-component.component.scss'] }) export class HeaderComponentComponent implements OnInit { route: string; dynamicTitle: string; pageTitle: string; burger: string; navStatus: boolean; constructor(location: Location, router: Router) { router.events.subscribe(val => { this.pageTitle = location.path(); this.pageTitle = this.pageTitle.substring(1); }); } ngOnInit() { } getTitle($event) { this.dynamicTitle = $event; } burgerStatus($event) { this.burger = $event; console.log($event); } getNavStatus($event) { this.navStatus = $event; console.log($event); } } 

Your input is much appreciated!

Answer 1

您可以创建属性来存储先前选择的值（在你的榜样about当你将鼠标放置在contact ，然后在mouseout将其分配给当前

Answer 2

You can Use TitleService for change your title on redirecting to your defined route.

Here is example

export class AppComponent {
  public constructor(private titleService: Title ) { }

  public setTitle( newTitle: string) {
    this.titleService.setTitle( newTitle );
  }
}

Answer 3

Don't you think, you are setting wrong model when event emits.

 getTitle($event) {
      // this.dynamicTitle = $event;
      this.pageTitle = $event;
  }