Signal Actions

SignalAction has lower boilerplate and follows Angular future vision. However old state approach is same performance efficient and eas to use

Next we need to tell component that it will use TodoActions

// todos.component.ts

import { ChangeDetectionStrategy, Component, ChangeDetectorRef } from '@angular/core';
import { TodoModel } from './../actions/todo.model';
import { TodosStateActions } from './../actions/todos.actions';

import { signalActions } from '@ng-state/store';

@Component({
  selector: 'todos',
  templateUrl: './todos.component.html',
  changeDetection: ChangeDetectionStrategy.OnPush
})
export class TodosComponent extends HasStateActions<TodosStateActions> {
  actions = signalActions(TodosStateActions);
}

There are cases where state path is dynamic. For example if we are using *ngFor directive and repeating todo.component we need to pass not only statePath but stateIndex as well because statePath is todos and stateIndex will be n So final path inside of todo.component will look like todos[stateIndex]

In this case we will create actions inside ngOnInit

// todo-item.component.ts

statePath = input<string[]>([]);
stateIndex = input<number>();

protected actions = signalActions(ResidentDetailsStateActions, { late: true });

ngOnInit(): void {
    this.actions.init({ 
        statePath: this.statePath, 
        stateIndex: this.stateIndex 
    });
}

statePath as well as stateIndex is passed from parent component like this:

<tr *ngFor="let todo of actions.state(); let i = index; trackBy: trackById">
    <th scope="row">{{ i + 1 }}</th>
    <td>{{ todo.name }}</td>
    <td>
        <todo-item [statePath]="actions.statePath" [stateIndex]="i"></todo-item>
    </td>
    <td><button class="btn btn-danger" (click)="deleteItem(i)">X</button></td>
</tr>

final actions statePath is stored in injected into propert statePath after actions beying constructed

stateIndex can also be set for in cases like when you want to pass item index via URL and want to load state according to it. More documentation on section: Passing list item index via router

You can use new Angular templte syntax @let to not repeat signal access

@let state = actions.state();
<span>{{ state.porp1 }}</span>
<span>{{ state.porp2 }}</span>

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