2

My App is based on JHipster and so the language services are provided by way of JhiLanguageService in the ng-jhipster library which uses a JhiConfigService to configure ngx-translate without my needing to import and configure the TranslateModule in my app.module. So when I add TranslateModule.forRoot(...) to imports of AppModule, everything breaks and I just see "translation not found..." messages everywhere.

I don't know how to make my lazy-loaded pages use the same translation service instance as the eager-loaded part of the app so that changing the language in an eagerly-loaded component of the nav bar affects the language used by the lazy-loaded pages.

I have looked into this idea and this idea but they both prescribe configuring TranslateModule in AppModule which breaks it and I don't know how to control ngx-translate configuration in a JHipster app.

Dan Cancro
  • 1,401
  • 5
  • 24
  • 53
  • Maybe this link helps: https://stackoverflow.com/questions/38987013/ng2-translate-not-working-in-lazy-loaded-module – duderoot Jul 11 '17 at 09:46
  • Thanks. I gave that a try too, but no luck. Apparently lazy loading modules is a known problem with JHipster Angular apps and they plan to address it in an upcoming release. – Dan Cancro Jul 11 '17 at 14:11

1 Answers1

1

I managed to fix translation in my lazy loaded module by adding BehaviorSubject to the JhiLanguageHelper service.

@Injectable()
export class JhiLanguageHelper {
    renderer: Renderer2 = null;
    private _language: BehaviorSubject<string>;

    constructor(
        private translateService: TranslateService,
        private rootRenderer: RendererFactory2,
        private findLanguageFromKeyPipe: FindLanguageFromKeyPipe,
        private titleService: Title,
        private router: Router
    ) {
        this._language = new BehaviorSubject<string>(this.translateService.currentLang);
        this.renderer = rootRenderer.createRenderer(document.querySelector('html'), null);
        this.init();
    }

    getAll(): Promise<any> {
        return Promise.resolve(LANGUAGES);
    }

    get language(): Observable<string> {
        return this._language.asObservable();
    }

    updateTitle(titleKey?: string) {
        if (!titleKey) {
             titleKey = this.getPageTitle(this.router.routerState.snapshot.root);
        }

        this.translateService.get(titleKey).subscribe((title) => {
            this.titleService.setTitle(title);
        });
    }

    private init() {
        this.translateService.onLangChange.subscribe((event: LangChangeEvent) => {
            this._language.next(this.translateService.currentLang);
            this.renderer.setAttribute(document.querySelector('html'), 'lang', this.translateService.currentLang);
            this.updateTitle();
            this.updatePageDirection();
        });
    }

    private getPageTitle(routeSnapshot: ActivatedRouteSnapshot) {
        let title: string = (routeSnapshot.data && routeSnapshot.data['pageTitle']) ? routeSnapshot.data['pageTitle'] : 'hcmGatewayApp';
        if (routeSnapshot.firstChild) {
            title = this.getPageTitle(routeSnapshot.firstChild) || title;
        }
        return title;
    }

    private updatePageDirection() {
        this.renderer.setAttribute(document.querySelector('html'), 'dir', this.findLanguageFromKeyPipe.isRTL(this.translateService.currentLang) ? 'rtl' : 'ltr');
    }
}

And you subscribe to the BehaviorSubject in your module like this.

export class YourModule {
    constructor(private languageService: JhiLanguageService, private languageHelper: JhiLanguageHelper) {
        this.languageHelper.language.subscribe((languageKey: string) => this.languageService.changeLanguage(languageKey));
    }
}
Džan Operta
  • 399
  • 2
  • 11