Checked attribute not working in mat-radio-button

Question

I am creating a radio button with the checked property but it's not showing selected

<mat-radio-group name="radioOpt1" [(ngModel)]="selectedRadio" [ngModelOptions]="{standalone: true}" (change)="radioChange($event)">
<mat-radio-button value="own" checked name="own">Own</mat-radio-button>
<mat-radio-button value="competitor" name="own">competitor</mat-radio-button> </mat-radio-group>

I want the first radio button to be checked by default

Answer 1

If using ngModel then you need to pass value of radio-button to ngModel.

<mat-radio-group name="radioOpt1" [(ngModel)]="selectedRadio" 
   [ngModelOptions]="{standalone: true}" (change)="radioChange($event)">
  <mat-radio-button value="own" name="own">Own</mat-radio-button>
  <mat-radio-button value="competitor" name="own">competitor</mat-radio-button> 
</mat-radio-group>

and ts file

 selectedRadio = 'own'; //default value

 radioChange(e){
   console.log(this.selectedRadio)
 }

or dynamically populated

 <mat-radio-group name="radioOpt1" [(ngModel)]="selectedRadio"
    [ngModelOptions]="{standalone: true}" (change)="radioChange($event)">
   <mat-radio-button *ngFor="let but of list" [value]="but.id" name="own" >
      {{but.name}}
   </mat-radio-button>
 </mat-radio-group>

ts file

  list = [{ "name": "own", id: "own"},{ "name": "competitor", id: "competitor"}];

  selectedRadio =this.list[0].id;