Does appRun support shared state? about apprun HOT 9 CLOSED

You can define a global state in a module and use an event to update and push the new global state to other components:

import app;
const global_state = {
  counter: 0
};
app.on('update-global-state', (delta) => {
  const new_state = { counter: global_state.counter + delta }
  app.run('global-state-changed', new_state)
})

In other components:

import app, { Component } from 'apprun';
export default class MyComponent extends Component {
  state = {}
  view = (state) => {
    return <div>
      {state.global_state.count}
      <button onclick={app.run('update-global-state', 1)}>+1</button>
      <button onclick={app.run('update-global-state', -1)}>-1</button>
    </div>
  }
  update = {
    'global-state-changed': (state, global_state) => ({ ...state, global_state })
  }
}

from apprun.

Having a globally shared state is possible. It is also possible to dispatch mutations/actions to the global state. However, the state is not reactive/observable. You do need to publish an event to advertise the change.

Vuex, Redux and AppRun pretty much all follow the Flux pattern:

Action => Dispatch => Store => View

The difference is how to refresh the View when the Store has changes.
Vuex gets the changes of the Store into the View using Vue's reactive system.
Redux Store has a store.subscribe function. The View subscribes to get the changes and refresh.
AppRun favor events over the reactive system.

(event) => Store => (event) => View

from apprun.

i read this soon after asking this question

https://medium.com/@yiyisun/deep-dive-into-apprun-state-3d6fb58b1521

but then , there will be instances where it makes sense to share state between/amongst components. hwo do you achieve that

from apprun.

After you change the global state, you publish a global event to let other components take action on it.

from apprun.

How and where is this global state defined if i may ask. seeing that each component has state, view and update objects

from apprun.

Me here again. I am looking at a scenario where the global shared state is reactive/observable like what you have in vuex. having to implement change event listeners and publishers everywhere manually might lead to loose ends . Is this possible ?

from apprun.

@yysun thanks so much for the explanation.

from apprun.

@yysun Me here again on global state, seeing the implementation of apprun-reactive using @nx-js/observer-util, it seems one can possibly get reactivity in a global state using observable properties and observers for (computed events). Can i use @nx-js/observer-util on a global state object /class as discussed above , or can the apprun-reactive decorator be used outside of a component. I am more interested in how a reactive state change from a global state object can cause a re-render of the view reflecting that change. I would rather not use event listeners to respond to state changes

from apprun.

Here are two examples of reactivity.
https://apprun.js.org/#play/17
https://apprun.js.org/#play/18

from apprun.