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Angular Material dialog: is there a way not to use the data property as "data.*" in the template?

I have a template like the one below:
card.component.html
<mat-card class="mat-elevation-z4">
<img mat-card-image src="{{ item.media_url }}" />
<mat-card-content class="custom">
<p>{{ item.caption }}</p>
</mat-card-content>
</mat-card>
It is a Material Card used inside a parent View that creates a grid with cards, each having a specific item.media_url and item.caption
events.component.ts
<div class="content">
<div fxLayout="row wrap" fxLayoutGap="16px grid">
<div
fxFlex="25%"
fxFlex.md="33%"
fxFlex.sm="50%"
fxFlex.xs="100%"
*ngFor="let item of events"
>
<app-card [item]="item" #myCard></app-card>
<button mat-button (click)="openDialog(myCard)">SCOPRI DI PIU'</button>
</div>
</div>
</div>
As you can see, inside the ngFor loop, below each card, there's a button that is supposed to open a dialog showing only one card at a time (the one above the clicked button in the grid).
I would like to put very the same card with its item.media_url and item.caption in this dialog, so I thought to use the data property of MatDialog to do this.
card.component.ts
import { Component, OnInit, Input, Inject, Optional } from '#angular/core';
import { MAT_DIALOG_DATA } from '#angular/material/dialog';
#Component({
selector: 'app-card',
templateUrl: './card.component.html',
styleUrls: ['./card.component.css']
})
export class CardComponent implements OnInit {
#Input() item : any;
constructor(#Optional() #Inject(MAT_DIALOG_DATA) public data: any) { }
ngOnInit(): void {
}
}
events.component.ts
import { Component, OnInit } from '#angular/core';
import { EventsService } from '../../shared/services/events.service';
import { MatDialog } from '#angular/material/dialog';
import { CardComponent } from 'src/app/shared/card/card.component';
#Component({
selector: 'app-events',
templateUrl: './events.component.html',
styleUrls: ['./events.component.css'],
})
export class EventsComponent implements OnInit {
events: any[];
constructor(private eventsService: EventsService, public dialog: MatDialog) {}
ngOnInit(): void {
this.getEvents();
}
getEvents(): void {
this.eventsService.getEvents().subscribe((response: any) => {
this.events = response.data;
console.log(this.events);
});
}
openDialog(card: any) {
this.dialog.open(CardComponent, {
data: {
item: card,
},
});
}
}
However, when I do this, I need to pass data to this.dialog.open(), not item, nor card.
Right now I am getting the error ERROR TypeError: ctx.item is undefined (which I perfectly understand why I am getting).
Is there a way I can somehow "alias" data as item, or maybe a better way to do this?

To make it work we did the following:
openDialog(card: CardComponent) { <-- strongly type
console.log(card.item); <-- access item
this.dialog.open(CardComponent, {
data: {
item: card.item <-- pass it as param
}
});
}
next in card.component.ts set the 'item` property.
constructor(#Optional() #Inject(MAT_DIALOG_DATA) public data: any) {
if (data) { <-- only if data is injected
this.item = data.item; <-- set item
}
}
Working Stackblitz

Robert's coment under your question answers the template / component part.
As for the data alias question, the answer is no. data is a property of the MatDialogConfig class, as shown here and to the best of my knowledge, you can't change it.

Angular - How can I toggle the visibility of an element in a component from another component?

I have the following scenario in my Angular app:
A component MainDashboardComponent that is visible when I have the route /. Obviously I have the <router-outlet> tag in my app.component.html file, which looks like this:
<app-side-menu></app-side-menu>
<div class="main-container">
<div class="content">
<router-outlet></router-outlet>
</div>
</div>
As you can see I have a SideMenuComponent I use to have a side menu on all my routes. In MainDashboardComponent I have a method that for some reason needs to toggle a chat element that is situated on the side menu.
Inside the SideMenuComponent I have a method that handles the visibility toggle for the chat element and it works as expected. How can I call this method from my MainDashboardComponent and toggle the chat element from there?
What I tried with no success
I tried to inject the SideMenuComponent inside my MainDashboardComponent but, though the method toggleChat() is called, the element doesn't change it's visibility. Looks like I have a kind of multiple instance of the same component I guess...
Can you please help me with this? Thank you!
MainDashboardComponent
import { Component, OnInit } from '#angular/core';
#Component({
selector: 'app-main-dashboard',
templateUrl: './main-dashboard.component.html',
styleUrls: ['./main-dashboard.component.scss']
})
export class MainDashboardComponent implements OnInit {
constructor() { }
ngOnInit() {}
setFocus(id) {
// here I'd like to call SideMenuComponent togglechat() ...
}
}
SideMenuComponent
import { Component, OnInit } from '#angular/core';
#Component({
selector: 'app-side-menu',
templateUrl: './side-menu.component.html',
styleUrls: ['./side-menu.component.scss']
})
export class SideMenuComponent implements OnInit {
showChat: boolean;
constructor() {
this.showChat = false;
}
ngOnInit() {
}
toggleChat() {
this.showChat = !this.showChat;
}
}

To communicate between different components, there are different ways.
If you want to communicate between parent and child component, you can use EventEmitter to emit event from child component and handle the event in your parent component
If you want to communicate between any components, you can use Service and implement communication with the help of EventEmitter or Subject/BehaviorSubject
In your case, we can create a service, myService.ts and declare and eventEmitter
.service.ts
#Injectable()
export class AppCommonService {
toggle : EventEmitter<boolean> = new EventEmitter<boolean>()
}
mainDashboard.component.ts
constructor(private myService : myService){}
chatStatus : boolean = false;
ngOnInit(){
this.myService.toggle.subscribe(status=>this.chatStatus = status);
}
toggleChat(){
this.myService.toggle.emit(!this.chatStatus);
}
sideMenu.component.ts
constructor(private myService : myService){}
chatStatus : boolean = false;
ngOnInit(){
this.myService.toggle.subscribe(status=>this.chatStatus = status);
}

Generally this is the domain of a service!
Just create a service and add the "showCat" property.
Inject the service into both components
Alter SideMenuComponent to:
toggleChat() {
this.myService.showChat = !this.myService.showChat;
}
Alter MainDashboardComponent, also use this.myService.showChat to show / hide your chat window
Service TS
#Injectable()
export class MyService{
showCat:boolean = true
}
MainDashboardComponent
toggleChat() {
this.myService.showChat = !this.myService.showChat;
}
SideMenuComponent
chatVisiblity = this.myService.showCat //<-- bind this to the element attribute

You could efficiently use child to parent communication in this scenario. You'll need to create a custom event using angular's EventEmitter in your SideMenuComponent and use it in your MainDashboardComponent.
So, here is some code that may help you -
// SideMenuComponent
import { Component, OnInit } from '#angular/core';
#Component({
selector: 'app-side-menu',
templateUrl: './side-menu.component.html',
styleUrls: ['./side-menu.component.scss']
})
export class SideMenuComponent implements OnInit {
#Output() valueChange = new EventEmitter();
showChat: boolean;
constructor() {
this.showChat = false;
}
ngOnInit() {
}
toggleChat() {
this.showChat = !this.showChat;
this.valueChange.emit(this.showChat);
}
}
// MainDashboardComponent
import { Component, OnInit } from '#angular/core';
#Component({
selector: 'app-main-dashboard',
template: `<app-side-menu (valueChange)='setFocus($event)'></app-side-menu>`
styleUrls: ['./main-dashboard.component.scss']
})
export class MainDashboardComponent implements OnInit {
constructor() { }
ngOnInit() { }
setFocus(event) {
// check for required input value
console.log(event);
}
}
Refer these tutorials if required -
https://dzone.com/articles/understanding-output-and-eventemitter-in-angular,
https://angular-2-training-book.rangle.io/handout/components/app_structure/responding_to_component_events.html

Angular #Output not working

Trying to do child to parent communication with #Output event emitter but is no working
here is the child component
import { Component, OnInit, Output, Input, EventEmitter } from '#angular/core';
#Component({
selector: 'app-emiter',
templateUrl: './emiter.component.html',
styleUrls: ['./emiter.component.css']
})
export class EmiterComponent implements OnInit {
#Output() emitor: EventEmitter<any>
constructor() { this.emitor = new EventEmitter()}
touchHere(){this.emitor.emit('Should Work');
console.log('<><><><>',this.emitor) // this comes empty
}
ngOnInit() {
}
}
this is the html template
<p>
<button (click)=" touchHere()" class="btn btn-success btn-block">touch</button>
</p>
The console.log inside the touchHere it shows nothing
even if I put this inside the parent component it show nothing as well
parent component
import { Component , OnInit} from '#angular/core';
// service I use for other stuff//
import { SenderService } from './sender.service';
// I dont know if I have to import this but did it just in case
import { EmiterComponent } from './emiter/emiter.component'
#Component({
selector: 'app-root',
templateUrl: './app.component.html',
styleUrls: ['./app.component.css']
})
export class AppComponent {
title = 'app';
user: any;
touchThis(message: string) {
console.log('Not working: ${message}');
}
constructor(private mySessionService: SenderService) { }
}
and here is the html template
<div>
<app-emiter>(touchHere)='touchThis($event)'</app-emiter>
</div>

Parent component template:
<app-emitor (emitor)='touchThis($event)'></app-emiter>
In parent template #Output should be 'called', not the child method.
Also, see: https://angular.io/guide/component-interaction#parent-listens-for-child-event

Here’s an example of how we write a component that has outputs:
#Component({
selector: 'single-component',
template: `<button (click)="liked()">Like it?</button>`
})
class SingleComponent {
#Output() putRingOnIt: EventEmitter<string>;
constructor() {
this.putRingOnIt = new EventEmitter();
}
liked(): void {
this.putRingOnIt.emit("oh oh oh");
}
}
Notice that we did all three steps: 1. specified outputs, 2. created an EventEmitter that we attached
to the output property putRingOnIt and 3. Emitted an event when liked is called.
If we wanted to use this output in a parent component we could do something like this:
#Component({
selector: 'club',
template: `
<div>
<single-component
(putRingOnIt)="ringWasPlaced($event)"
></single-component>
</div>`
})
class ClubComponent {
ringWasPlaced(message: string) { console.log(`Put your hands up: ${message}`);
} }
// logged -> "Put your hands up: oh oh oh"
Again, notice that:
putRingOnIt comes from the outputs of SingleComponent
ringWasPlaced is a function on the ClubComponent
$event contains the thing that wasemitted, in this case a string

<app-emiter (emitor)="touchThis($event)" ></app-emiter>
By using #Output() you should apply the event you need to emit in the directive of the emitter component.Adding the name of the variable to the the directive and but the emitted over function inside the quotation passing the $event.

touchHere() is the method from which you are binding some value to emit with your EventEmitter. And your EventEmitter is 'emitor'.
So your code will work if you simply do the below:
<app-emiter (emitor)='touchThis($event)'></app-emiter>

How to rendered dynamically created array component on template html in Angular2?

I have created dynamic component instances by selecting pre-existing components. For example,
#Component({
selector: 'dynamic-component',
template: `<div #container><ng-content></ng-content></div>`
})
export class DynamicComponent {
#ViewChild('container', {read: ViewContainerRef}) container: ViewContainerRef;
public addComponent(ngItem: Type<WidgetComponent>,selectedPlugin:Plugin): WidgetComponent {
let factory = this.compFactoryResolver.resolveComponentFactory(ngItem);
const ref = this.container.createComponent(factory);
const newItem: WidgetComponent = ref.instance;
newItem.pluginId = Math.random() + '';
newItem.plugin = selectedPlugin;
this._elements.push(newItem);
return newItem;
}
}
My pre-existed components are ChartWidget and PatientWidget which extended the class WidgetComponent that I wanted to add in the container. For example,
#Component({
selector: 'chart-widget',
templateUrl: 'chart-widget.component.html',
providers: [{provide: WidgetComponent, useExisting: forwardRef(() => ChartWidget) }]
})
export class ChartWidget extends WidgetComponent implements OnInit {
constructor(ngEl: ElementRef, renderer: Renderer) {
super(ngEl, renderer);
}
ngOnInit() {}
close(){
console.log('close');
}
refresh(){
console.log('refresh');
}
...
}
chart-widget.compoment.html (using primeng Panel)
<p-panel [style]="{'margin-bottom':'20px'}">
<p-header>
<div class="ui-helper-clearfix">
<span class="ui-panel-title" style="font-size:14px;display:inline-block;margin-top:2px">Chart Widget</span>
<div class="ui-toolbar-group-right">
<button pButton type="button" icon="fa-window-minimize" (click)="minimize()"</button>
<button pButton type="button" icon="fa-refresh" (click)="refresh()"></button>
<button pButton type="button" icon="fa-expand" (click)="expand()" ></button>
<button pButton type="button" (click)="close()" icon="fa-window-close"></button>
</div>
</div>
</p-header>
some data
</p-panel>
data-widget.compoment.html (same as chart-widget using primeng Panel)
#Component({
selector: 'data-widget',
templateUrl: 'data-widget.component.html',
providers: [{provide: WidgetComponent, useExisting: forwardRef(() =>DataWidget) }]
})
export class DataWidget extends WidgetComponent implements OnInit {
constructor(ngEl: ElementRef, renderer: Renderer) {
super(ngEl, renderer);
}
ngOnInit() {}
close(){
console.log('close');
}
refresh(){
console.log('refresh');
}
...
}
WidgetComponent.ts
#Component({
selector: 'widget',
template: '<ng-content></ng-content>'
})
export class WidgetComponent{
}
Now I added the components by selecting a component from the existed components (e.g. chart-widget and data-widget) in the following way and stored the instances into an array.
#Component({
templateUrl: 'main.component.html',
entryComponents: [ChartWidget, DataWidget],
})
export class MainComponent implements OnInit {
private elements: Array<WidgetComponent>=[];
private WidgetClasses = {
'ChartWidget': ChartWidget,
'DataWidget': DataWidget
}
#ViewChild(DynamicComponent) dynamicComponent: DynamicComponent;
addComponent(): void{
let ref= this.dynamicComponent.addComponent(this.WidgetClasses[this.selectedComponent], this.selectedComponent);
this.elements.push(ref);
this.dynamicComponent.resetContainer();
}
}
Now, I am facing problem to render the components using innerHtml in main.component.html. It render the html but I am not able to use button click event or other event on it. I have also tried to render chart using primeng but its also not working.
main.component.html
<dynamic-component [hidden]="true" ></dynamic-component>
<widget *ngFor="let item of elements">
<div [innerHTML]="item._ngEl.nativeElement.innerHTML | sanitizeHtml">
</div>
</widget>
I have also implemented a sanitizeHtml Pipe but its giving still same result. So, as I understand innerHTML is only showing the html data but I can't use any button event as well as the js chart. I have also tried to show the items like this {{item}} under tag. But it display like a text [object object]. So, could anyone give a solution for it? How can I render the components allowing the button events and js chart? Thanks.
EDIT: See my Plunker here https://plnkr.co/edit/lugU2pPsSBd3XhPHiUP1?p=preview
You can see here, it is possible to add chart or data widget dynamically and I am showing it using innerHTML. So, the button events are not working here. If I coding like {{item}} then it shows [object object] text. You can also see in console the component array data. The main Question is, How can I active the button events on it (e.g. if i click close or refresh button then it will call the related functions)?

I would create structural directive like:
view.directive.ts
import { ViewRef, Directive, Input, ViewContainerRef } from '#angular/core';
#Directive({
selector: '[view]'
})
export class ViewDirective {
constructor(private vcRef: ViewContainerRef) {}
#Input()
set view(view: ViewRef) {
this.vcRef.clear();
this.vcRef.insert(view);
}
ngOnDestroy() {
this.vcRef.clear()
}
}
then
app.component.ts
private elements: Array<{ view: ViewRef, component: WidgetComponent}> = [];
...
addComponent(widget: string ): void{
let component = this.dynamicComponent.addComponent(this.WidgetClasses[widget]);
let view: ViewRef = this.dynamicComponent.container.detach(0);
this.elements.push({view,component});
this.dynamicComponent.resetContainer();
}
and
app.component.html
<widget *ngFor="let item of elements">
<ng-container *view="item.view"></ng-container>
</widget>
So i have just moved view from dynamic component container to desired place.
Plunker Example

How can I pass the FormGroup of a parent component to its child component using the current Form API

I would like to pass the parent component's FormGroup to its child for the purpose of displaying an error-message using the child.
Given the following parent:
parent.component.ts
import { Component, OnInit } from '#angular/core'
import {
REACTIVE_FORM_DIRECTIVES, AbstractControl, FormBuilder, FormControl, FormGroup, Validators
} from '#angular/forms'
#Component({
moduleId: module.id,
selector: 'parent-cmp',
templateUrl: 'language.component.html',
styleUrls: ['language.component.css'],
directives: [ErrorMessagesComponent]
})
export class ParentCmp implements OnInit {
form: FormGroup;
first: AbstractControl;
second: AbstractControl;
constructor(private _fb: FormBuilder) {
this.first = new FormControl('');
this.second = new FormControl('')
}
ngOnInit() {
this.form = this._fb.group({
'first': this.first,
'second': this.second
});
}
}
I would now like to pass the form:FormGroup variable above to the child component below:
error-message.component.ts
import { Component, OnInit, Input } from '#angular/core'
import { NgIf } from '#angular/common'
import {REACTIVE_FORM_DIRECTIVES, FormGroup } from '#angular/forms'
#Component({
moduleId: module.id,
selector: 'epimss-error-messages',
template: `<span class="error" *ngIf="errorMessage !== null">{{errorMessage}}</span>`,
styles: [],
directives: [REACTIVE_FORM_DIRECTIVES, NgIf]
})
export class ErrorMessagesComponent implements OnInit {
#Input() ctrlName: string
constructor(private _form: FormGroup) { }
ngOnInit() { }
get errorMessage() {
// Find the control in the Host (Parent) form
let ctrl = this._form.find(this.ctrlName);
console.log('ctrl| ', ctrl);
// for (let propertyName of ctrl.errors) {
// // If control has a error
// if (ctrl.errors.hasOwnProperty(propertyName) && ctrl.touched) {
// // Return the appropriate error message from the Validation Service
// return CustomValidators.getValidatorErrorMessage(propertyName);
// }
// }
return null;
}
The constructor formGroup represents the FormGroup of the parent - in its present form it does not work.
I am trying to follow this obsolete example at http://iterity.io/2016/05/01/angular/angular-2-forms-and-advanced-custom-validation/

In the parent component do this:
<div [formGroup]="form">
<div>Your parent controls here</div>
<your-child-component [formGroup]="form"></your-child-component>
</div>
And then in your child component you can get hold of that reference like so:
export class YourChildComponent implements OnInit {
public form: FormGroup;
// Let Angular inject the control container
constructor(private controlContainer: ControlContainer) { }
ngOnInit() {
// Set our form property to the parent control
// (i.e. FormGroup) that was passed to us, so that our
// view can data bind to it
this.form = <FormGroup>this.controlContainer.control;
}
}
You can even ensure either formGroupName or [formGroup] is specified on your component by changing its selector like so:
selector: '[formGroup] epimss-error-messages,[formGroupName] epimss-error-messages'
This answer should be sufficient for your needs, but if you want to know more I've written a blog entry here:
https://mrpmorris.blogspot.co.uk/2017/08/angular-composite-controls-formgroup-formgroupname-reactiveforms.html

For Angular 11 I tried all the above answers, and in different combinations, but nothing quite worked for me. So I ended up with the following solution which worked for me just as I wanted.
TypeScript
#Component({
selector: 'fancy-input',
templateUrl: './fancy-input.component.html',
styleUrls: ['./fancy-input.component.scss']
})
export class FancyInputComponent implements OnInit {
valueFormGroup?: FormGroup;
valueFormControl?: FormControl;
constructor(
private formGroupDirective: FormGroupDirective,
private formControlNameDirective: FormControlName
) {}
ngOnInit() {
this.valueFormGroup = this.formGroupDirective.form;
this.valueFormControl = this.formGroupDirective.getControl(this.formControlNameDirective);
}
get controlName() {
return this.formControlNameDirective.name;
}
get enabled() {
return this.valueFormControl?.enabled
}
}
HTML
<div *ngIf="valueFormGroup && valueFormControl">
<!-- Edit -->
<div *ngIf="enabled; else notEnabled" [formGroup]="valueFormGroup">
<input class="input" type="text" [formControlName]="controlName">
</div>
<!-- View only -->
<ng-template #notEnabled>
<div>
{{valueFormControl?.value}}
</div>
</ng-template>
</div>
Usage
Note that I had to add ngDefaultControl otherwise it would give no default value accessor error in console (if somebody knows how to get rid of it without error - will be much appreciated).
<form [formGroup]="yourFormGroup" (ngSubmit)="save()">
<fancy-input formControlName="yourFormControlName" ngDefaultControl></fancy-input>
</form>

this is an example of child component used inside parent formGroup :
child component ts:
import { Component, OnInit, Input } from '#angular/core';
import { FormGroup, ControlContainer, FormControl } from '#angular/forms';
#Component({
selector: 'app-date-picker',
template: `
<mat-form-field [formGroup]="form" style="width:100%;">
<input matInput [matDatepicker]="picker" [placeholder]="placeHolder" [formControl]="control" readonly>
<mat-datepicker-toggle matSuffix [for]="picker"></mat-datepicker-toggle>
<mat-datepicker #picker></mat-datepicker>
</mat-form-field>
<mat-icon (click)="clearDate()">replay</mat-icon>`,
styleUrls: ['./date-picker.component.scss']
})
export class DatePickerComponent implements OnInit {
public form: FormGroup;
public control : FormControl;
#Input() controlName : string;
#Input() placeHolder : string;
constructor(private controlContainer: ControlContainer) {
}
clearDate(){
this.control.reset();
}
ngOnInit() {
this.form = <FormGroup>this.controlContainer.control;
this.control = <FormControl>this.form.get(this.controlName);
}
}
css date picker :
mat-icon{
position: absolute;
left: 83%;
top: 31%;
transform: scale(0.9);
cursor: pointer;
}
and used like this :
<app-date-picker class="col-md-4" [formGroup]="feuilleForm" controlName="dateCreation" placeHolder="Date de création"></app-date-picker>

Parent Component :
#Component({
selector: 'app-arent',
templateUrl: `<form [formGroup]="parentFormGroup" #formDir="ngForm">
<app-child [formGroup]="parentFormGroup"></app-child>
</form> `
})
export class ParentComponent implements {
parentFormGroup :formGroup
ngOnChanges() {
console.log(this.parentFormGroup.value['name'])
}
}
Child Component :
#Component({
selector: 'app-Child',
templateUrl: `<form [formGroup]="childFormGroup" #formDir="ngForm">
<input id="nameTxt" formControlName="name">
</form> `
})
export class ChildComponent implements OnInit {
#Input() formGroup: FormGroup
childFormGroup :FormGroup
ngOnInit() {
// Build your child from
this.childFormGroup.addControl('name', new FormControl(''))
/* Bind your child form control to parent form group
changes in 'nameTxt' directly reflect to your parent
component formGroup
*/
this.formGroup.addControl("name", this.childFormGroup.controls.name);
}
}

The ngOnInit was important - this did not work in the constructor.
And I prefer looking for the FormControlDirective - its the first one found in the child component's ancestor hierarchy
constructor(private formGroupDirective: FormGroupDirective) {}
ngOnInit() {
this.formGroupDirective.control.addControl('password', this.newPasswordControl);
this.formGroupDirective.control.addControl('confirmPassword', this.confirmPasswordControl);
this.formGroup = this.formGroupDirective.control;
}

I would do this in this way, i have passed child form data as group to parent so you can have separated form data in submit call.
Parent:
<form [formGroup]="registerStudentForm" (ngSubmit)="onSubmit()">
<app-basic-info [breakpoint]="breakpoint" [formGroup]="registerStudentForm"></app-basic-info>
<button mat-button>Submit</button>
</form>
Child:
<mat-card [formGroup]="basicInfo">
<mat-card-title>Basic Information</mat-card-title>
<mat-card-content>
<mat-grid-list
[gutterSize]="'20px'"
[cols]="breakpoint"
rowHeight="60px"
>
<mat-grid-tile>
<mat-form-field appearance="legacy" class="full-width-field">
<mat-label>Full name</mat-label>
<input matInput formControlName="full_name" />
</mat-form-field>
</mat-grid-tile>
</mat-grid-list>
</mat-card-content>
</mat-card>
Parent.ts:
export class RegisterComponent implements OnInit {
constructor() { }
registerForm = new FormGroup({});
onSubmit() {
console.warn(this.registerForm.value);
}
}
Child.ts
export class BasicInfoComponent implements OnInit {
#Input() breakpoint;
#Input() formGroup: FormGroup;
basicInfo: FormGroup;
constructor() { }
ngOnInit(): void {
this.basicInfo = new FormGroup({
full_name: new FormControl('Riki maru'),
dob: new FormControl(''),
});
this.formGroup.addControl('basicInfo', this.basicInfo);
}
}
Here in your child form components #Input() formGroup: FormGroup; part would be reference of parent component

I would pass the form as an input to the child component;
#Component(
{
moduleId: module.id,
selector: 'epimss-error-messages',
template: `
<span class="error" *ngIf="errorMessage !== null">{{errorMessage}}</span>`,
styles: [],
directives: [REACTIVE_FORM_DIRECTIVES, NgIf]
})
export class ErrorMessagesComponent implements OnInit {
#Input()
ctrlName: string
#Input('form') _form;
ngOnInit() {
this.errorMessage();
}
errorMessage() {
// Find the control in the Host (Parent) form
let ctrl = this._form.find(this.ctrlName);
console.log('ctrl| ', ctrl)
// for (let propertyName of ctrl.errors) {
// // If control has a error
// if (ctrl.errors.hasOwnProperty(propertyName) && ctrl.touched) {
// // Return the appropriate error message from the Validation Service
// return CustomValidators.getValidatorErrorMessage(propertyName);
// }
// }
return null;
}
And of course you'll need o pass the form from the parent component to the child, which you can do it in different ways , but the simplest is :
Somewhere in your parent ;
<epimss-error-messages [form]='form'></epimss-error-messages>

If you want to access the parent from the child component, you can access parent property of the FormControl instance, https://angular.io/api/forms/AbstractControl#parent
To get the parent error:
const parent = control.parent;
const errors = parent.errors;