Transifex

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Localize Angular applications

Note

You can start using Transifex Native by creating a Transifex Native project.

You can easily localize Angular components using the @transifex/angular library extension.

Installation

Install the extension library using:

npm install @transifex/angular --save

Initialization

In order to use the TX Native object globally, it is necessary to initialize the library in the angular application bootstrap, in two locations:

  • NgModule initialization
@NgModule({
  declarations: [
    AppComponent,
    LoginComponent,
    TermsComponent,
    HomeComponent,
    PrivacyComponent
  ],
  imports: [
    AppRoutingModule,
    BrowserModule,

    // TX Native module declaration
    TxNativeModule.forRoot(),
  ],
  providers: [,
  ],
  bootstrap: [AppComponent]
})


  • Application Boostrap
import { Component } from '@angular/core';
import { TranslationService } from '@transifex/angular';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.scss']
})
export class AppComponent {
  constructor(private translationService: TranslationService) {
    // TX Native library intialization
    translationService.init({
      token: '----- here your TX Native token ------',
    });
  }

  async ngOnInit() {
    await this.translationService.getLanguages();
    await this.translationService.setCurrentLocale('el');
  }
}

Usage

Use the T component to mark strings for translation based on the example below.

  <p>
    <label>
      <T str="Password" key="label.password"></T>
    </label>
    <input type="password" name="password" />
  </p>

Available optional props are:

  • context [String] String context, affects key generation
  • key [String] Custom string key
  • comment [String] Developer comment
  • charlimit [Number] Character limit instruction for translators
  • tags [String] Comma separated list of tags
  • escapeVars [Boolean] If escaping should be applied to ICU variables
  • sanitize [Boolean] Safe render of the HTML result after translation takes place
  • vars [Object] ICU variables to render in the string


The T component can sanitize the translated result if HTML is involved, using the parameter sanitize, ie this would be possible:

  <p>
    <T
      str="By proceeding you agree to the {terms_of_services} and {privacy_policy}."
      key="text.agree_message"
      [sanitize]=true
      [vars]="{ terms_of_services: '<a href=\'terms\'>' + terms + '</a>',
        privacy_policy: '<a href=\'privacy\'>' + privacy + '</a>'
      }">
    </T>
  </p>


This will render like this in English:

<span>By proceeding you agree to the <a href="terms">terms of service</a> and <a href="privacy">privacy policy</a>.</span>


And like this in Greek:

<span>Συνεχίζοντας, αποδέχεστε τους <a href="terms">όροι χρήσης</a> και τους <a href="privacy">πολιτική απορρήτου</a>.</span>


The same block without the sanitize option would be like this, for Greek:

Συνεχίζοντας, αποδέχεστε τους &lt;a href='terms'&gt;όροι χρήσης&lt;/a&gt; και τους &lt;a href='privacy'&gt;πολιτική απορρήτου&lt;/a&gt;.

The main thing to keep in mind is that the str property to the T component must always be a valid ICU message format template.

UT component has the same behavior as T component, but renders source string as HTML inside a div tag or a span tag if inline property is true.

  <p>
    <UT
      str="Copyright {year} by Transifex."
      key="text.copyright"
      [inline]=false
      comment="This is the current year"
      [vars]="{ year: '&copy; 2020' }">
    </UT>
  </p>

Available optional props are the same as the T component but has escapeVars property enabled by default, and:

  • inline [Boolean] If should wrap the translation with span (true) of with a div (default, if false)

TranslationService service

This is the main service exposed from the SDK in order to intialize the TX Native object.

In your bootstrap entry point in the Angular application, you should initialize the SDK, like this:

import { Component } from '@angular/core';
import { TranslationService } from '@transifex/angular';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.scss']
})
export class AppComponent {
  title = 'TX Native Angular Demo';

  constructor(private translationService: TranslationService) {
    translationService.init({
      token: '----- here your TX Native token ------',
    });
  }

  async ngOnInit() {
    await this.translationService.getLanguages();
    await this.translationService.setCurrentLocale('el');
  }
}

The translation service is a singleton instance so the initialization will be shared across the whole application.

Exposes the following methods and properties:

  • init [config (1)] Initializes the TX Native object
  • setCurrentLocale [locale] Set the current locale in the TX Native object
  • getCurrentLocale [no params] Returns the current locale of the TX Native object
  • getLanguages [no params] Returns an array of available languages
  • translate [translate params (2)] Returns the translation for a string with given translation params


(1) Initialization config

export interface ITranslationServiceConfig {
  token: string;
  cdsHost?: string;
  filterTags?: string;
  cache?: () => void;
  missingPolicy?: () => void;
  errorPolicy?: () => void;
}

cache, missingPolicy and errorPolicy are set by default by @transifex/native package but you can provide if you wish custom functions of your own, or use another policy provided by the @transifex/native package.

Please check the documentation related to this on@transifex/native package here.

(2) Translation params:

str: string // string to be translated
params: Record<string, unknown> // an object with the params and variables

The params should follow the interface:

export interface ITranslateParams {
  _context?: string;
  _comment?: string;
  _charlimit?: number;
  _tags?: string;
  _key?: string;
  _escapeVars?: boolean;
  _inline?: boolean;
  sanitize?: boolean;
}

@T Decorator

This is a decorator for using inside classes and components in order to have properties with the translation and used them in code and templates.

An example of use is the following:

import { Component, OnInit } from '@angular/core';
import { Router } from '@angular/router';
import { T, TranslationService } from '@transifex/angular';

@Component({
  selector: 'app-login',
  templateUrl: './login.component.html',
  styleUrls: ['./login.component.scss']
})
export class LoginComponent implements OnInit {
  // Translations using decorator
  @T('Monday', { _key: 'text.monday' })
  weekday: string;
  @T('terms of service', { _key: 'text.terms_of_service' })
  terms: string;
  @T('privacy policy', { _key: 'text.privacy_policy' })
  privacy: string;

  constructor(
    private translationService: TranslationService,
    private router: Router) {}

  login() {
    this.router.navigateByUrl('home');
  }
}

and the use of the properties in the template:

  <p>
    <T
      str="By proceeding you agree to the {terms_of_services} and {privacy_policy}."
      key="text.agree_message"
      [sanitize]=true
      [vars]="{ terms_of_services: '<a href=\'#/terms\'>' + terms + '</a>',
        privacy_policy: '<a href=\'#/privacy\'>' + privacy + '</a>'
      }"
    ></T>
  </p>

Language Picker Component

Renders a <select> tag that displays supported languages and switches the application's selected language on change. Uses Translation Service internally.

The html selector is tx-language-picker.

This is an example of use for the language picker component:

<tx-language-picker
  className="placeBottomLeft"
  (localeChanged)="onLocaleChanged($event)"></tx-language-picker>

and the event for locale changed inside the component could be:

import { Component, OnInit } from '@angular/core';
import { Router } from '@angular/router';
import { T, TranslationService } from '@transifex/angular';

@Component({
  selector: 'app-login',
  templateUrl: './login.component.html',
  styleUrls: ['./login.component.scss']
})
export class LoginComponent implements OnInit {
  onLocaleChanged(event) {
    // here we can do any action when locale changes
  }
}

Accepts properties:

  • className: The CSS class that will be applied to the <select> tag

Returns:

  • localeChanged: event for handling the change of locale

You always can implement a language picker of your choice, injecting the TranslationService and using the different methods provided, such as getLanguages.