2023Angular学习之聊聊notification（自定义服务）

// notification.service.ts

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

// 通知状态的枚举
export enum NotificationStatus {
  Process = "progress",
  Success = "success",
  Failure = "failure",
  Ended = "ended"
}

@Injectable({
  providedIn: 'root'
})
export class NotificationService {

  private notify: Subject<NotificationStatus> = new Subject();
  public messageObj: any = {
    primary: '',
    secondary: ''
  }

  // 转换成可观察体
  public getNotification(): Observable<NotificationStatus> {
    return this.notify.asObservable();
  }

  // 进行中通知
  public showProcessNotification() {
    this.notify.next(NotificationStatus.Process)
  }

  // 成功通知
  public showSuccessNotification() {
    this.notify.next(NotificationStatus.Success)
  }

  // 结束通知
  public showEndedNotification() {
    this.notify.next(NotificationStatus.Ended)
  }

  // 更改信息
  public changePrimarySecondary(primary?: string, secondary?: string) {
    this.messageObj.primary = primary;
    this.messageObj.secondary = secondary
  }

  constructor() { }
}

notification                                          
├── notification.component.html                     // 页面骨架
├── notification.component.scss                     // 页面独有样式
├── notification.component.spec.ts                  // 测试文件
└── notification.component.ts                       // javascript 文件

<!-- notification.component.html -->

<!-- 支持手动关闭通知 -->
<button (click)="closeNotification()">关闭</button>
<h1>提醒的内容: {{ message }}</h1>
<!-- 自定义重点通知信息 -->
<p>{{ primaryMessage }}</p>
<!-- 自定义次要通知信息 -->
<p>{{ secondaryMessage }}</p>

// notification.component.scss

:host {
  position: fixed;
  top: -100%;
  right: 20px;
  background-color: #999;
  border: 1px solid #333;
  border-radius: 10px;
  width: 400px;
  height: 180px;
  padding: 10px;
  // 注意这里的 active 的内容，在出现通知的时候才有
  &.active {
    top: 10px;
  }
  &.success {}
  &.progress {}
  &.failure {}
  &.ended {}
}

// notification.component.ts

import { Component, OnInit, HostBinding, OnDestroy } from '@angular/core';
// 新的知识点 rxjs
import { Subscription } from 'rxjs';
import {debounceTime} from 'rxjs/operators';
// 引入相关的服务
import { NotificationStatus, NotificationService } from 'src/app/services/notification.service';

@Component({
  selector: 'app-notification',
  templateUrl: './notification.component.html',
  styleUrls: ['./notification.component.scss']
})
export class NotificationComponent implements OnInit, OnDestroy {
  
  // 防抖时间，只读
  private readonly NOTIFICATION_DEBOUNCE_TIME_MS = 200;
  
  protected notificationSubscription!: Subscription;
  private timer: any = null;
  public message: string = ''
  
  // notification service 枚举信息的映射
  private reflectObj: any = {
    progress: "进行中",
    success: "成功",
    failure: "失败",
    ended: "结束"
  }

  @HostBinding('class') notificationCssClass = '';

  public primaryMessage!: string;
  public secondaryMessage!: string;

  constructor(
    private notificationService: NotificationService
  ) { }

  ngOnInit(): void {
    this.init()
  }

  public init() {
    // 添加相关的订阅信息
    this.notificationSubscription = this.notificationService.getNotification()
      .pipe(
        debounceTime(this.NOTIFICATION_DEBOUNCE_TIME_MS)
      )
      .subscribe((notificationStatus: NotificationStatus) => {
        if(notificationStatus) {
          this.resetTimeout();
          // 添加相关的样式
          this.notificationCssClass = `active ${ notificationStatus }`
          this.message = this.reflectObj[notificationStatus]
          // 获取自定义首要信息
          this.primaryMessage = this.notificationService.messageObj.primary;
          // 获取自定义次要信息
          this.secondaryMessage = this.notificationService.messageObj.secondary;
          if(notificationStatus === NotificationStatus.Process) {
            this.resetTimeout()
            this.timer = setTimeout(() => {
              this.resetView()
            }, 1000)
          } else {
            this.resetTimeout();
            this.timer = setTimeout(() => {
              this.notificationCssClass = ''
              this.resetView()
            }, 2000)
          }
        }
      })
  }

  private resetView(): void {
    this.message = ''
  }
  
  // 关闭定时器
  private resetTimeout(): void {
    if(this.timer) {
      clearTimeout(this.timer)
    }
  }

  // 关闭通知
  public closeNotification() {
    this.notificationCssClass = ''
    this.resetTimeout()
  }
  
  // 组件销毁
  ngOnDestroy(): void {
    this.resetTimeout();
    // 取消所有的订阅消息
    this.notificationSubscription.unsubscribe()
  }

}

// app.component.html

<router-outlet></router-outlet>
<app-notification></app-notification>

// user-list.component.html

<button (click)="showNotification()">click show notification</button>

// user-list.component.ts

import { NotificationService } from 'src/app/services/notification.service';

// ...
constructor(
  private notificationService: NotificationService
) { }

// 展示通知
showNotification(): void {
  this.notificationService.changePrimarySecondary('主要信息 1');
  this.notificationService.showProcessNotification();
  setTimeout(() => {
    this.notificationService.changePrimarySecondary('主要信息 2', '次要信息 2');
    this.notificationService.showSuccessNotification();
  }, 1000)
}