# Rules of Thumb

## You probably don't need NgRx

* **Consider**
  * **Service with Behavior Subject**
  * **Container Presenter**
  * **Easy upgrade path to NgRx**

## Container/Presenter

### Container

* **Interacts with the store**
* **Pass observable streams via async pipe**
* **Receive events from child presenter components**
* **Decide what to do with events/data**

{% embed url="<https://stackblitz.com/edit/tour-of-heroes-container-presenter?file=src%2Fapp%2Ffeatures%2Fdashboard%2Fcontainers%2Fdashboard%2Fdashboard.component.ts&view=editor>" %}

### Presenter

* **Receive plain data from parent**
* **Display data/make it pretty**
* **User/system events are raised to parent via emitters**
  * **Decisions are deferred**
  * **Component is reusable and flexible**
* **No knowledge of stores, services, selectors, actions, etc.**

{% embed url="<https://stackblitz.com/edit/tour-of-heroes-container-presenter?file=src%2Fapp%2Ffeatures%2Fdashboard%2Fcomponents%2Ftop-heroes-list%2Ftop-heroes-list.component.ts&view=editor>" %}

{% hint style="info" %}
Refactor Tour of Heroes to use Container Presenter <https://stackblitz.com/github/jessesanders/tour-of-heroes>
{% endhint %}


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