I am new to angular. I am dynamically rendering some fields into my reactive form. Everything works great when I am using ng serve with a mock request (i.e. rendering happens properly, no error in the console.log). As soon as I build the project with ng build and use a proper backend, I get the error for each field I am rendering dynamically:
main.js:1 ERROR TypeError: Cannot read property '_rawValidators' of null
I couldn't find any background on this error. I would love to hear your thoughts.
// these fields change with selection
this.datafields = [{
dfId: 48,
dfName: "Phone",
dfType: "text",
dfOptions: null,
dfValue: ""
},
{
dfId: 49,
dfName: "Eval",
dfType: "select",
dfOptions: ["","Remote","Live"],
df_value: "",
}]
typescript rendering in ngOnInit (tried ngAfterViewInit with no improvement)
dfGroup = new FormGroup({})
...
...
this.eyeForm = this.formBuilder.group({
focus: ['', Validators.required],
datafields: this.formBuilder.array([])
})
...
...
if (this.datafields != null || this.datafields != undefined) {
this.datafields.forEach((x:any) => {
this.dfGroup.setControl(x.dfName, new FormControl(x.dfValue));
});
this.getDataFields.push(this.dfGroup);
}
and HTML looks like the following:
<div [formGroup]="dfGroup">
<div class="row pt-2" *ngFor="let field of datafields; let i=index">
<div class="col-4 d-flex align-items-center 13required">
{{field.dfName}}
</div>
<div class="col-6">
<mat-form-field *ngIf="field.dfType == 'text'" appearance="outline">
<input
matInput
[type]="field.dfType"
[formControlName]="field.dfName"
required
/>
</mat-form-field>
<mat-form-field
*ngIf="field.dfType == 'select'"
appearance="outline"
>
<mat-select [formControlName]="field.dfName" placeholder="">
<mat-option
[value]="option"
*ngFor="let option of field.dfOptions"
>
{{ option }}
</mat-option>
</mat-select>
</mat-form-field>
</div>
</div>
</div>
I had a similar issue, you need to add an extra div with property [formGroupName]="i",
The final code would be,
<div [formGroup]="dfGroup">
<div class="row pt-2" *ngFor="let field of datafields; let i=index">
<div [formGroupName]="i">
<div class="col-4 d-flex align-items-center 13required">
{{field.dfName}}
</div>
<div class="col-6">
<mat-form-field *ngIf="field.dfType == 'text'" appearance="outline">
<input matInput [type]="field.dfType" [formControlName]="field.dfName" required />
</mat-form-field>
<mat-form-field *ngIf="field.dfType == 'select'" appearance="outline">
<mat-select [formControlName]="field.dfName" placeholder="">
<mat-option [value]="option" *ngFor="let option of field.dfOptions">
{{ option }}
</mat-option>
</mat-select>
</mat-form-field>
</div>
</div>
</div>
</div>
I ran in to this situation when I was mocking out my template and typo'd my formControlName attribute.
<mycomponent formControlName="bogusfieldSpelledWrong" ...>
Why Angular showed it as this error likely has something to do with how the component was initializing/changing the form.
it must be about formControlName. check out your form control names in ts file and html file. for nested groups you can use formGroupName, then use formControlName.
this.yourForm = this.fb.group({
name: [''],
contact: this.fb.group({
address: ['']
})
})
<form [formGroup]="yourForm">
<input type="text" formControlName="name" />
<div formGroupName="contact">
<input type="text" formControlName="address" />
</div>
</form>