Translating Forms

The Form Engine offers two complementary mechanisms for localizing what users see: ngx-translate for translating schema labels, and the labelMap input for resolving labels that the schema doesn't define at all.

Translating labels with ngx-translate

The engine pipes rendered text through ngx-translate (opens in a new tab): question labels, checkbox, radio and select option labels, and helper and validation text. The translation keys are the label strings from the schema itself, and keys with no translation render unchanged — so a form with no translations configured simply shows its schema labels.

FormEntryModule imports and re-exports TranslateModule, but configuring it is the consumer's job. In your application module:

import { TranslateModule } from '@ngx-translate/core';
 
@NgModule({
  imports: [TranslateModule.forRoot(), FormEntryModule]
})
export class AppModule {}

Then supply translations for the current language — from a loader, or programmatically:

import { TranslateService } from '@ngx-translate/core';
 
constructor(private translate: TranslateService) {}
 
ngOnInit() {
  this.translate.currentLang = 'fr';
  this.translate.setTranslation('fr', {
    'Encounter Details': 'Détails de la rencontre',
    'Visit date': 'Date de visite',
    Provider: 'Fournisseur'
  });
}

Resolving missing labels with labelMap

Schemas don't have to define a label for every question or answer. For questions and answers that only specify a concept, the renderer can look the display text up in the labelMap object you bind to it:

<form [formGroup]="form.rootNode.control">
  <ofe-form-renderer
    [node]="form.rootNode"
    [labelMap]="labelMap"
  ></ofe-form-renderer>
</form>

labelMap is keyed by concept UUIDs (for question labels) and answer values (for answer labels):

labelMap = {
  'a8ae88a4-1350-11df-a1f1-0026b9348838': 'WHO stage criteria',
  'a899b35c-1350-11df-a1f1-0026b9348838': 'Yes',
  'a899b42e-1350-11df-a1f1-0026b9348838': 'No'
};

The renderer only consults labelMap for labels the schema leaves empty; labels defined in the schema always win. A typical implementation traverses the form for unlabeled concepts and fetches their display names from the concept dictionary — the demo app's traverseForUnlabeledConcepts shows the pattern.