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angular - 使用 rxjs Observable 订阅 mobx @observable 但未在深层组件（ts 文件）中进行更改

问题描述

我正在尝试使用 rxjs observable 从 angular-mobx 商店获取更改。但如果观察到的数组发生变化，则不会从那里得到任何变化。但是，如果我使用“=”符号分配新值，那么我会在订阅中得到更改。任何人都可以解释吗？或仅通过更改（例如拼接或替换数组中的对象）来帮助更改？谢谢

https://stackblitz.com/edit/angular-reuych DEMO APP

import { computed, action, observable } from "mobx-angular";
import {observe  } from "mobx";
import { Observable } from 'rxjs';
import { Injectable } from "@angular/core";
import * as moment from "moment-timezone";
@Injectable()
export class Store {toRx(obj, prop) {
   return Observable.create(observer =>
      observe(obj, prop, (change) => observer.next(change.newValue), true)
    );
  }
  @observable storeCampaigns:any=[];

}

然后在像这样订阅的组件中

this.store.toRx(this.store.storeCampaigns, 'campaigns')
  .subscribe(val =>  {
  console.log("calendar get change", val)

标签： angularrxjsobservableangular7mobx

解决方案

如果您深入了解，mobx您将到达以下链接观察者，您可以在其中找到以下评论

/**
 * A node in the state dependency root that observes other nodes, and can be observed itself.
 *
 * ComputedValue will remember the result of the computation for the duration of the batch, or
 * while being observed.
 *
 * During this time it will recompute only when one of its direct dependencies changed,
 * but only when it is being accessed with `ComputedValue.get()`.
 *
 * Implementation description:
 * 1. First time it's being accessed it will compute and remember result
 *    give back remembered result until 2. happens
 * 2. First time any deep dependency change, propagate POSSIBLY_STALE to all observers, wait for 3.
 * 3. When it's being accessed, recompute if any shallow dependency changed.
 *    if result changed: propagate STALE to all observers, that were POSSIBLY_STALE from the last step.
 *    go to step 2. either way
 *
 * If at any point it's outside batch and it isn't observed: reset everything and go to 1.
 */

这几乎表明只有在第一次访问该值（即订阅时）或依赖项发生更改时（即当您更改存储的参考资料，在您的情况下与=商店内的操作员一起使用）。

因此，如果我必须对其工作方式进行总结，则其行为与其他状态管理库非常相似，它们仅在商店中的某些 ref 发生更改时才向其订阅者推送新值。

** 免责声明，不是 mobx pro，但这就是源代码所说的。

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