What you need to build mobile decentralized applications using Flutter

Introduction

Building decentralized applications is not only a trend of 2021 but a need. A need that in most cases presents a solution as a Web decentralized platform. The tools to use are well known are documented, but what about mobile apps? Can we build dApps to be used on our phones?

The answer is yes. I will explain in this article some of the tools we can use and how a mobile dApp can be built.
Regarding programming language, I use Flutter since it went live in 2018, and my…

One of many payment methods for cryptocurrencies

Most of the last web projects I worked on included cryptocurrency in some way or another, especially payment gateways for accepting Bitcoin, Ethereum, and other coins as payment. Most of them included the feature of hosted checkout, where a link is generated to display to the users. This link has a QR to pay, with email and callback notifications. Having callback notifications we can process a payment as paid or failed, and both parties (Admin and final users) are notified of the status of the payment.

Coinqvest features different SDKs (Although we can…

Get live prices of BTC, ETH, TRX, and other cryptocurrencies using NodeJS

CoinGecko is a free API tool to fetch cryptocurrency prices, publicly available and without limits. At the moment of writing this post, they track more than 6285 coins, and the data is reliable regarding time and delays.

This tutorial presents a basic guide on how to use CoinGecko on NodeJS using the CoinGecko-API library (https://github.com/miscavage/CoinGecko-API), which is a wrapper to interact with the API.

To install it, we use the npm install command:

npm install coingecko-apiconst CoinGecko = require('coingecko-api');

And the new can start fetching prices with…

Add a splash screen or loading spinner in Flutter Web.

Introduction

In addition to mobile applications Flutter has introduced web support, which generates web content rendered using the standard web technology stack: HTML, CSS, and JavaScript. This way, you can compile existing Flutter code written in Dart into a web project that can be embedded in the browser and deployed to any web server.

At the moment of writing this post (December 2020) a lot of standard mobile Flutter libraries have already added web support, extending the functionality that we already know for mobile apps, now for web applications. …

Build your own components to use with React.js and Next.js in 5 minutes

Years ago when I made my first approach to the React.js environment, I came up with different concepts with different naming. One of those concepts is Higher Order Component (Or HOC), which is without doubt one of the features I like (and use) the most.

As React official documentation says:

A higher-order component (HOC) is an advanced technique in React for reusing component logic. HOCs are not part of the React API, per se. They are a pattern that emerges from React’s compositional nature. …

This is the second part of the tutorial, which is divided into 2 parts:

— Part 1: Setting up the project, and animating the top left and top right squares.

— Part 2: Animating the bottom left and bottom right squares, as well as fading in the text

We are building an animation for the logo of Arcaweb, a swiss company based in the heart of Agno, Ticino.

The final source code is available on https://github.com/juancurti/flutteranimationtutorial

Our goal is the following:

In this tutorial, we will learn how to build a complex animation using Flutter, based on the logo of Arcaweb.

Arcaweb is a swiss company based in the heart of Agno, Ticino, as an active member of the Swiss tech scene, developing software solutions for companies and startups. Its logo presents three red squares and a rotated grey square; next to it, there’s the company name with two different text formats:

Introduction

As developers, we found ourselves very often in situations where we need to protect certain data or variables not only from potential attacks but from users as well. When developing a mobile application, a web platform, even a single page application we use to rely on different libraries or third-party services (for instance Google Maps for location, Facebook or Google for signing in, and so on), as well as API credentials (being on our very own server or an external one), and SSH-keys for remote connection. In synthesis, we are speaking of sensitive information.

To keep our code safe and…