Javascript 角形4型母管和路由器插座

假设我们有以下代码：

---

您可以通过以下方式完成此项工作：

[style.background-color]="getBackgroundColor()"

在component.ts中：

constructor(private router: Router) { }

ngOnInit() {
    this.router.events.subscribe((route: any) => this.route= route);
}
getBackgroundColor() {
    if (this.url) {
        if (this.route.url === '/yourRoute'{
        return 'white'
        } else {
        return '#6772e5'
        }
    } else {
        return '#6772e5'
    }
}

---

有几种方法可以做到这一点。如果希望父组件在某个子组件处于活动状态时更改样式，则需要进行一些编码才能完成

方法1：共享服务 您需要创建一个共享服务来控制父组件订阅的状态。方法“emitChange”将更改状态“fillColorSubject”，该状态作为可观察的“fillColor”返回以订阅

填充颜色服务。ts：

import { Observable } from 'rxjs/Observable';
import { Injectable } from '@angular/core';
import { Subject } from 'rxjs/Subject';

@Injectable()

export class FillColorService {
    private fillColorSubject = new Subject<boolean>();
    fillColor = this.fillColorSubject.asObservable();
    emitChange(fill : boolean) {
        this.fillColorSubject.next(fill);
    }
}

import { Component, OnInit, OnDestroy } from '@angular/core';
import { FillColorService } from 'fill-color-service';

@Component( {
  templateUrl: 'my.component.html'
} )

export class myComponent implements OnInit, OnDestroy {

  constructor ( private _fillColorService: FillColorService ) {
  }

  ngOnInit() {
    this._fillColorService.emitChange(true);
  }

  ngOnDestroy() {
    this._fillColorService.emitChange(false);
  }
}

import { Component } from '@angular/core';
import { FillColorService } from 'fill-color-service';

@Component( {
  templateUrl: 'parent.component.html'
} )

export class parentComponent {
  fillColumn : boolean;

  constructor ( private _fillColorService: FillColorService ) {
    _fillColorService.fillColor .subscribe(
      fill => {
        this.fillColumn = fill;
      });
  }
}

<div class="container">
    <div class="row">
        <div class="col-sm-4 col-md-3">
            <app-sidebar></app-sidebar>
        </div>
        <div class="col-sm-8 col-md-9" [ngClass]="{ 'fill': fillColumn }">
            <app-component></app-component>
        </div>
    </div>
</div>

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

@Component( {
  templateUrl: 'parent.component.html'
} )

export class parentComponent {
  fillColumn : boolean;

  fillColor( fill : boolean = false ) {
    this.fillColumn = fill;
  }
}

import { Component, Output, EventEmitter, OnInit, OnDestroy } from '@angular/core';

@Component( {
  selector: 'app-component',
  templateUrl: 'my.component.html'
} )

export class myComponent implements OnInit, OnDestroy {
  @Output() fillParentColor = new EventEmitter<boolean>();

  ngOnInit() {
    this.fillParentColor.emit(true);
  }

  ngOnDestroy() {
    this.fillParentColor.emit(false);
  }
}

<div class="container">
    <div class="row">
        <div class="col-sm-4 col-md-3">
            <app-sidebar></app-sidebar>
        </div>
        <div class="col-sm-8 col-md-9" [ngClass]="{ 'fill': fillColumn }">
            <app-component (fillParentColor)="fillColor($event)"></app-component>
        </div>
    </div>
</div>

现在，父组件将需要订阅该服务。当状态更改时，开关（fillColumn）将更改列状态

父.component.ts：

import { Observable } from 'rxjs/Observable';
import { Injectable } from '@angular/core';
import { Subject } from 'rxjs/Subject';

@Injectable()

export class FillColorService {
    private fillColorSubject = new Subject<boolean>();
    fillColor = this.fillColorSubject.asObservable();
    emitChange(fill : boolean) {
        this.fillColorSubject.next(fill);
    }
}

import { Component, OnInit, OnDestroy } from '@angular/core';
import { FillColorService } from 'fill-color-service';

@Component( {
  templateUrl: 'my.component.html'
} )

export class myComponent implements OnInit, OnDestroy {

  constructor ( private _fillColorService: FillColorService ) {
  }

  ngOnInit() {
    this._fillColorService.emitChange(true);
  }

  ngOnDestroy() {
    this._fillColorService.emitChange(false);
  }
}

import { Component } from '@angular/core';
import { FillColorService } from 'fill-color-service';

@Component( {
  templateUrl: 'parent.component.html'
} )

export class parentComponent {
  fillColumn : boolean;

  constructor ( private _fillColorService: FillColorService ) {
    _fillColorService.fillColor .subscribe(
      fill => {
        this.fillColumn = fill;
      });
  }
}

<div class="container">
    <div class="row">
        <div class="col-sm-4 col-md-3">
            <app-sidebar></app-sidebar>
        </div>
        <div class="col-sm-8 col-md-9" [ngClass]="{ 'fill': fillColumn }">
            <app-component></app-component>
        </div>
    </div>
</div>

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

@Component( {
  templateUrl: 'parent.component.html'
} )

export class parentComponent {
  fillColumn : boolean;

  fillColor( fill : boolean = false ) {
    this.fillColumn = fill;
  }
}

import { Component, Output, EventEmitter, OnInit, OnDestroy } from '@angular/core';

@Component( {
  selector: 'app-component',
  templateUrl: 'my.component.html'
} )

export class myComponent implements OnInit, OnDestroy {
  @Output() fillParentColor = new EventEmitter<boolean>();

  ngOnInit() {
    this.fillParentColor.emit(true);
  }

  ngOnDestroy() {
    this.fillParentColor.emit(false);
  }
}

<div class="container">
    <div class="row">
        <div class="col-sm-4 col-md-3">
            <app-sidebar></app-sidebar>
        </div>
        <div class="col-sm-8 col-md-9" [ngClass]="{ 'fill': fillColumn }">
            <app-component (fillParentColor)="fillColor($event)"></app-component>
        </div>
    </div>
</div>

您的模板需要能够通过条件类反映更改

parent.component.html：

import { Observable } from 'rxjs/Observable';
import { Injectable } from '@angular/core';
import { Subject } from 'rxjs/Subject';

@Injectable()

export class FillColorService {
    private fillColorSubject = new Subject<boolean>();
    fillColor = this.fillColorSubject.asObservable();
    emitChange(fill : boolean) {
        this.fillColorSubject.next(fill);
    }
}

import { Component, OnInit, OnDestroy } from '@angular/core';
import { FillColorService } from 'fill-color-service';

@Component( {
  templateUrl: 'my.component.html'
} )

export class myComponent implements OnInit, OnDestroy {

  constructor ( private _fillColorService: FillColorService ) {
  }

  ngOnInit() {
    this._fillColorService.emitChange(true);
  }

  ngOnDestroy() {
    this._fillColorService.emitChange(false);
  }
}

import { Component } from '@angular/core';
import { FillColorService } from 'fill-color-service';

@Component( {
  templateUrl: 'parent.component.html'
} )

export class parentComponent {
  fillColumn : boolean;

  constructor ( private _fillColorService: FillColorService ) {
    _fillColorService.fillColor .subscribe(
      fill => {
        this.fillColumn = fill;
      });
  }
}

<div class="container">
    <div class="row">
        <div class="col-sm-4 col-md-3">
            <app-sidebar></app-sidebar>
        </div>
        <div class="col-sm-8 col-md-9" [ngClass]="{ 'fill': fillColumn }">
            <app-component></app-component>
        </div>
    </div>
</div>

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

@Component( {
  templateUrl: 'parent.component.html'
} )

export class parentComponent {
  fillColumn : boolean;

  fillColor( fill : boolean = false ) {
    this.fillColumn = fill;
  }
}

import { Component, Output, EventEmitter, OnInit, OnDestroy } from '@angular/core';

@Component( {
  selector: 'app-component',
  templateUrl: 'my.component.html'
} )

export class myComponent implements OnInit, OnDestroy {
  @Output() fillParentColor = new EventEmitter<boolean>();

  ngOnInit() {
    this.fillParentColor.emit(true);
  }

  ngOnDestroy() {
    this.fillParentColor.emit(false);
  }
}

<div class="container">
    <div class="row">
        <div class="col-sm-4 col-md-3">
            <app-sidebar></app-sidebar>
        </div>
        <div class="col-sm-8 col-md-9" [ngClass]="{ 'fill': fillColumn }">
            <app-component (fillParentColor)="fillColor($event)"></app-component>
        </div>
    </div>
</div>

然后，子myComponent需要发出一个带有布尔值的事件（fillParentColor），以触发父更改

my.component.ts：

import { Observable } from 'rxjs/Observable';
import { Injectable } from '@angular/core';
import { Subject } from 'rxjs/Subject';

@Injectable()

export class FillColorService {
    private fillColorSubject = new Subject<boolean>();
    fillColor = this.fillColorSubject.asObservable();
    emitChange(fill : boolean) {
        this.fillColorSubject.next(fill);
    }
}

import { Component, OnInit, OnDestroy } from '@angular/core';
import { FillColorService } from 'fill-color-service';

@Component( {
  templateUrl: 'my.component.html'
} )

export class myComponent implements OnInit, OnDestroy {

  constructor ( private _fillColorService: FillColorService ) {
  }

  ngOnInit() {
    this._fillColorService.emitChange(true);
  }

  ngOnDestroy() {
    this._fillColorService.emitChange(false);
  }
}

import { Component } from '@angular/core';
import { FillColorService } from 'fill-color-service';

@Component( {
  templateUrl: 'parent.component.html'
} )

export class parentComponent {
  fillColumn : boolean;

  constructor ( private _fillColorService: FillColorService ) {
    _fillColorService.fillColor .subscribe(
      fill => {
        this.fillColumn = fill;
      });
  }
}

<div class="container">
    <div class="row">
        <div class="col-sm-4 col-md-3">
            <app-sidebar></app-sidebar>
        </div>
        <div class="col-sm-8 col-md-9" [ngClass]="{ 'fill': fillColumn }">
            <app-component></app-component>
        </div>
    </div>
</div>

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

@Component( {
  templateUrl: 'parent.component.html'
} )

export class parentComponent {
  fillColumn : boolean;

  fillColor( fill : boolean = false ) {
    this.fillColumn = fill;
  }
}

import { Component, Output, EventEmitter, OnInit, OnDestroy } from '@angular/core';

@Component( {
  selector: 'app-component',
  templateUrl: 'my.component.html'
} )

export class myComponent implements OnInit, OnDestroy {
  @Output() fillParentColor = new EventEmitter<boolean>();

  ngOnInit() {
    this.fillParentColor.emit(true);
  }

  ngOnDestroy() {
    this.fillParentColor.emit(false);
  }
}

<div class="container">
    <div class="row">
        <div class="col-sm-4 col-md-3">
            <app-sidebar></app-sidebar>
        </div>
        <div class="col-sm-8 col-md-9" [ngClass]="{ 'fill': fillColumn }">
            <app-component (fillParentColor)="fillColor($event)"></app-component>
        </div>
    </div>
</div>

import{Component，Output，EventEmitter，OnInit，ondestory}来自'@angular/core'；
@组件（{
选择器：“应用程序组件”，
templateUrl:'my.component.html'
} )
导出类myComponent实现OnInit、OnDestroy{
@Output（）fillParentColor=neweventemitter（）；
恩戈尼尼特（）{
this.fillParentColor.emit（true）；
}
恩贡德斯特罗（）{
this.fillParentColor.emit（false）；
}
}

最后，您的模板需要能够在发出子事件时触发父组件事件。触发myComponent的“fillParentColor”事件时，将使用布尔参数触发parentComponent的“fillColor”事件。您还需要根据“fillColumn”开关为列添加条件类（fill）

parent.component.html：

import { Observable } from 'rxjs/Observable';
import { Injectable } from '@angular/core';
import { Subject } from 'rxjs/Subject';

@Injectable()

export class FillColorService {
    private fillColorSubject = new Subject<boolean>();
    fillColor = this.fillColorSubject.asObservable();
    emitChange(fill : boolean) {
        this.fillColorSubject.next(fill);
    }
}

import { Component, OnInit, OnDestroy } from '@angular/core';
import { FillColorService } from 'fill-color-service';

@Component( {
  templateUrl: 'my.component.html'
} )

export class myComponent implements OnInit, OnDestroy {

  constructor ( private _fillColorService: FillColorService ) {
  }

  ngOnInit() {
    this._fillColorService.emitChange(true);
  }

  ngOnDestroy() {
    this._fillColorService.emitChange(false);
  }
}

import { Component } from '@angular/core';
import { FillColorService } from 'fill-color-service';

@Component( {
  templateUrl: 'parent.component.html'
} )

export class parentComponent {
  fillColumn : boolean;

  constructor ( private _fillColorService: FillColorService ) {
    _fillColorService.fillColor .subscribe(
      fill => {
        this.fillColumn = fill;
      });
  }
}

<div class="container">
    <div class="row">
        <div class="col-sm-4 col-md-3">
            <app-sidebar></app-sidebar>
        </div>
        <div class="col-sm-8 col-md-9" [ngClass]="{ 'fill': fillColumn }">
            <app-component></app-component>
        </div>
    </div>
</div>

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

@Component( {
  templateUrl: 'parent.component.html'
} )

export class parentComponent {
  fillColumn : boolean;

  fillColor( fill : boolean = false ) {
    this.fillColumn = fill;
  }
}

import { Component, Output, EventEmitter, OnInit, OnDestroy } from '@angular/core';

@Component( {
  selector: 'app-component',
  templateUrl: 'my.component.html'
} )

export class myComponent implements OnInit, OnDestroy {
  @Output() fillParentColor = new EventEmitter<boolean>();

  ngOnInit() {
    this.fillParentColor.emit(true);
  }

  ngOnDestroy() {
    this.fillParentColor.emit(false);
  }
}

<div class="container">
    <div class="row">
        <div class="col-sm-4 col-md-3">
            <app-sidebar></app-sidebar>
        </div>
        <div class="col-sm-8 col-md-9" [ngClass]="{ 'fill': fillColumn }">
            <app-component (fillParentColor)="fillColor($event)"></app-component>
        </div>
    </div>
</div>

---

谢谢你，旺德里尔