角度-检查多个子组件窗体是否脏

Question

I have some bunch of child components holding a form - value for the form will be send from the parent components - i have looped the child components in the parent and passed the data to the components

Child Component

<form #formType="ngForm">
    <div class="col-lg-4" *ngFor="let data of productSizes; let i = index;">
        <div class="inlinediv" *ngFor="let item of data.ItemDetails">
            <div class="marginright15 inlinediv">
                <ng-container *ngIf="item.Foundation">
                    <b>{{item.Size.toUpperCase()}}</b><br />
                    <input *ngFor="let val of item.Foundation" type="text" appNumbericInput maxlength="4" [(ngModel)]="val.Val" class="inputcustom text-right" [disabled]="(val.Val == null ? true : false) || disableChecker" (input)="enableSave=true" />
                </ng-container>
            </div>
        </div>
    </div>
</form>

Child Component.ts

@Component({
    selector: 'app-base-mattress',
    templateUrl: './base-mattress.component.html',
    styleUrls: ['./base-mattress.component.css']
})

export class BaseMattressComponent implements OnInit {
    @Input() productSizes: IItemDetails[];
    @ViewChild('formType') formVariable: NgForm;
    blobURL: string = environment.blobURL;
    constructor() {}
    ngOnInit() {}
}

Parent Component html

<ng-container *ngFor="let slot of slotRequests; let j = index;">
    <ng-container *ngIf="slot.ItemGrouping.toLowerCase() === 'mattress'">
        <ng-container *ngFor="let data of slotRequests[j].Data; let i = index;">
            <app-base-mattress [productSizes]="data"></app-base-mattress>
        </ng-container>
    </ng-container>
</ng-container>

Now my problem is that i want to read the child component form variable? I don't want a service to subscribe and check whether the form dirty, i have tried it many times it doesn't work.

I have tried to map my child with template reference variable like this <app-base-mattress [productSizes]="data" #childData></app-base-mattress> but it seems I'm looping the child component so it doesn't seem to act as an reference variable for specific component - Please help me to find out how can i read the child component form variable

Working version of my StackBlitz

Thanks in advance !!

Answer 1

use form element in your top level component

<form #formType="ngForm">
    <ng-container *ngFor="let slot of slotRequests; let j = index;">
        <ng-container *ngIf="slot.ItemGrouping.toLowerCase() === 'mattress'">
            <ng-container>

                <div *ngFor="let data of slotRequests[j].Data; let i = index;">
                    <app-base-mattress [productSizes]="data.ItemDetails"></app-base-mattress>
                </div>

            </ng-container>
        </ng-container>
    </ng-container>
</form>

Use viewproviders to provide controncontainer which is super class for formDirectives the use existing ngForm group group together your form

import { Component, OnInit, ViewChild, Input } from '@angular/core';
import { NgForm, ControlContainer } from '@angular/forms'

@Component({
  selector: 'app-base-mattress',
  templateUrl: './base-mattress.component.html',
  styleUrls: ['./base-mattress.component.css'],
  viewProviders: [{ provide: ControlContainer, useExisting: NgForm }]
})
export class BaseMattressComponent implements OnInit {
  @Input() productSizes: any[];

  constructor() { }

  ngOnInit() {
  }

}

Example: https://stackblitz.com/edit/angular-ch5yh2

Answer 2

You can do this:

parent.component.html :

<app-base-mattress #childCmp [productSizes]="data"></app-base-mattress>

parent.component.ts :

@ViewChildren('childCmp ')
childCmps: QueryList<BaseMattressComponent>;

and then iterate through them to achieve desired results

this.childCmps.forEach((item) => {
...
});