ngModel cannot be used to register form controls with a parent formGroup directive

Question

After upgrading to RC5 we began getting this error:

ngModel cannot be used to register form controls with a parent formGroup 
 directive.
Try using formGroup's partner directive "formControlName" instead.  Example:

    <div [formGroup]="myGroup">
      <input formControlName="firstName">
    </div>

    In your class:

    this.myGroup = new FormGroup({
       firstName: new FormControl()
    });

      Or, if you'd like to avoid registering this form control,
 indicate that it's standalone in ngModelOptions:

      Example:

      
  <div [formGroup]="myGroup">
     <input formControlName="firstName">
     <input [(ngModel)]="showMoreControls" [ngModelOptions]="{standalone: true}">
  </div>

It looks like in RC5 the two can no longer be used together, but I could not find an alternative solution.

Here is the component producing the exception:

    <select class="field form-control" [formGroup]="form" [(ngModel)]="cause.id" [name]="name">
    <option *ngFor="let c of causes" [value]="c.text">{{c.text}}</option>
    </select>

Answer 1

The answer is right on the error message, you need to indicate that it's standalone and therefore it doesn't conflict with the form controls:

[ngModelOptions]="{standalone: true}"