Ralph's Blog about this and that (RSS | Atom)

Consume Protocol Buffer messages with Ionic

Published: 14. January 2017  •  Updated: 1. December 2018  •  ionic, spring, java, javascript

Form validation with Angular and Spring Boot

Published: 26. January 2017  •  Updated: 4. December 2018  •  angular, ionic, spring, java, javascript

Example of form validation in an Ionic Angular application. How to create custom synchronous and asynchronous validators and how to validate data on the server with the Jakarta Bean Validation framework.

Integrate ECharts into an Ionic app

Published: 22. February 2017  •  Updated: 17. March 2026  •  ionic, javascript

In this post, we look at a way to display charts from the ECharts library in an Ionic app

JWT Authentication with Ionic/Angular and Spring Boot

Published: 5. February 2017  •  Updated: 17. March 2026  •  ionic, spring, java, javascript

How to implement a JWT authentication system with Ionic/Angular and Spring Boot.

Offline capable Ionic Web App with IndexedDB

Published: 15. September 2017  •  Updated: 3. December 2018  •  database, javascript, ionic

Example of an Ionic web application that stores data in IndexedDB and works offline.

Spring Boot and Ionic application development with OpenAPI

Published: 21. September 2017  •  Updated: 4. December 2018  •  spring, java, javascript, ionic

In this blog, we create REST services in Spring Boot and consume them in an Ionic app. We use the OpenAPI specification for generating API documentation and the client TypeScript code.

Dynamically loading position data with Ionic and Spring Boot

Published: 5. November 2017  •  Updated: 3. December 2018  •  ionic, java, spring, javascript

In this blog post we create an Ionic app that dynamically requests location data points from a Spring Boot server and displays them on an OpenStreetMap map. The data points are stored in a MongoDB database, and we take advantage of the geospatial query support to read the data points only for a certain area.

Adding speech recognition to an Ionic App

Published: 18. December 2017  •  Updated: 17. March 2026  •  ionic, javascript, java, spring

In this blog post I present two different ways to integrate speech recognition functionality into an Ionic app: the Web Speech API and RecordRTC together with the Google Cloud Speech API.

Custom SVG icons with Ionic

Published: 6. January 2018  •  Updated: 21. March 2026  •  ionic, angular, javascript

How to use custom SVG icons in a current Ionic application

Using Dexie.js in a TypeScript application

Published: 12. January 2018  •  Updated: 21. March 2026  •  database, javascript, ionic

This blog post shows how to use Dexie in a TypeScript application

A closer look at the Background Sync API

Published: 26. June 2018  •  pwa, javascript, java, spring, ionic

This blog post takes a closer look at the Background Sync API, shows how to use it as a progressive enhancement, and presents an example that synchronizes data between an Ionic web application and a Spring Boot server application.

Using the Background Sync API with the Angular service worker

Published: 9. December 2018  •  pwa, javascript, ionic

In this blog post, we combine Angular's generated service worker with custom Background Sync logic in an Ionic and Angular application.

Google Cloud Vision and Storage example with Ionic and Spring Boot

Published: 11. December 2018  •  java, spring, ionic, javascript

This post shows how to upload images from an Ionic web application directly to Google Cloud Storage with V4 signed URLs and analyze them with Google Cloud Vision from a Spring Boot back end.

Integrate FontAwesome icons in an Angular application

Published: 15. February 2019  •  Updated: 20. March 2026  •  javascript, ionic

This blog post shows how to integrate Font Awesome icons into a modern standalone Angular and Ionic application with the official Angular library.

Stateless Authentication with Spring Security

Published: 15. May 2019  •  java, spring, ionic

This post implements a stateless authentication system with Spring Security, Spring Boot, and an Angular/Ionic client

Password auto-login with the Credential Management API

Published: 13. June 2019  •  java, javascript, spring, ionic

How to create a frictionless password auto-login experience with the Credential Management API.

Google Fonts in an Angular / Ionic application

Published: 10. June 2019  •  javascript, ionic

A tutorial on how to use Google Fonts in an Angular / Ionic app. The blog post presents two approaches. One approach links to the Google Fonts service, and the second approach shows how to self-host the fonts in your application.

Reliable file uploads over HTTP with tus.io

Published: 11. June 2019  •  Updated: 19. March 2026  •  java, javascript, spring, ionic

How to integrate tus.io implementations into JavaScript and Java applications to create reliable and resumable file uploads over HTTP.

Uploading pictures from Capacitor app to Spring Boot

Published: 11. June 2019  •  Updated: 19. March 2026  •  java, spring, javascript, ionic, capacitor

How to take pictures with the Capacitor camera plugin and upload them to a Spring Boot application with Angular's HttpClient and tus.io.

Creating a passwordless sign-in with WebAuthn, Spring, and Ionic/Angular

Published: 25. August 2019  •  Updated: 20. March 2026  •  javascript, java, spring, ionic

In this blog post, we build a passwordless sign-in flow with WebAuthn, an Ionic / Angular front end, and a Spring Boot back end secured with Spring Security.

Push Notifications with Capacitor and Java

Published: 3. April 2020  •  Updated: 20. June 2021  •  ionic, spring, javascript, capacitor, java

In this blog post, we take a closer look at how to receive push notifications with Capacitor and how to send them from a Spring Boot application.

Add CAPTCHA to your site with hCaptcha

Published: 1. May 2020  •  Updated: 20. May 2021  •  javascript, java, ionic, angular

This blog post shows you how to integrate hCaptcha CAPTCHAs into a plain JavaScript project and Angular projects, with a Spring Boot back end.

Dexie.js live queries

Published: 22. January 2022  •  javascript, database, ionic

In this blog post, I will show you an example of the new live query feature in Dexie.js 3.2 that enables an application to subscribe to IndexedDB queries.

Running an LLM in the browser with Transformers.js

Published: 27. October 2024  •  ionic, angular, llm

Run an LLM in a web application with Transformers.js.

Speech Recognition in the Browser with Transformers.js

Published: 19. January 2025  •  ionic, angular, llm

Running the Moonshine model, a speech recognition model, in the browser with Transformers.js. The demo application is a snake game controlled by voice commands.

PocketBase - Deploy to Production

Published: 20. July 2025  •  angular, ionic, baas

This blog post shows how to deploy a JavaScript application with PocketBase as the backend on a Debian 13 server.

PocketBase - Develop JavaScript Application

Published: 20. July 2025  •  angular, ionic, baas

This blog post shows how to develop a simple Ionic/Angular application with PocketBase as the backend.

Building a JavaScript Application with Appwrite Backend

Published: 5. September 2025  •  angular, ionic, baas

This blog post demonstrates how to develop a simple Ionic/Angular application with Appwrite as the backend.