A Fun and Friendry Introduction to XMPP (Comic Style)

We’ve lately been experimenting with different teaching styles for our students.Inspired by some awesome work by Julia Evans we thought it was worthwhile to package out teaching material into a comic/infographic style to help students grasp concepts fast. Here is the first version I cooked up over the weekend. If you want the full PDF version of the booklet, jump to the end of the page and type in your email. You’ll get it in your inbox. Feel free to send us your feedback right here or on twitter.Continue reading

Sending and Receiving Files with XMPP : Http File Upload Explained



In the previous tutorials, we covered the basics on XMPP and visited the Roster and saw how you can add your contacts in XMPP. In this one, we’re tackling an important problem of sending and receiving files.Everybody expects an instant messenger these days to be able to send and receive any kind of file. XMPP being one of the competing Instant Messaging Protocols, has attempted to come up with ways to allow the sending and receiving of files but most of the techniques highly depend on there being a single peer to peer connection( sender to receiver) over which the files are sent.

This becomes a problem in today’s expectations where you need to send the files in group chats, multiple connected clients on the same account. Simply put, a better tool for the job was needed and most people where alreadyContinue reading

A Friendly Introduction to NGINX

NGINX is a powerful web server. Right. If you’re here you probably know that already so I won’t spend more time convincing you it is also a noteworthy reverse proxy and load balancer. Many have reported the lack of a simple serial and step by step guide to help a complete beginner feel comfortable with NGNIX, in this guide, we set out to provide one and at the end, we do hope, you’ll be able to more confidently manage your NGINX instance and make critical decisions particular to your needs.Continue reading

A friendly introduction to SQL (MYSQL)

SQL is the language used to manipulate relational databases. In this tutorial, we are laying down the foundations of working with SQL using one of its implementations MYSQL. MYSQL is an open source database system used by millions of systems out there. While working with your database, you usually want to do basic stuff like creating or dropping(deleting) databases, adding tables to the database, dropping tables form the database, or just routine CRUD operations on your tables.Continue reading

Android Smack XMPP Introduction:Building a Simple Client

rooster_full_chat_processedXmpp is a protocol for Presence and Messaging , and Smack is a Java/android implementation of the protocol that helps developers build fast client applications.When one embarks on the journey to build android chat apps based on xmpp using Smack ,there are a lot of pitfalls one can come across as you are trying to combine the three worlds of Java , Android and the Xmpp protocol itself to build one coherent product.This tutorial aims at documenting these and possible ways to mitigate them.By the end of this tutorial ,you will have an android chat client that can connect to and XMPP server , send and receive messages .Most importantly ,you will learn the android plumbing necessary to get all this rolling.Lets get started.Shall we.Continue reading

Android Health App Design : Saving Data in SQLite Database

android_sqliteThe last tutorial left our health android app ,Imirire usable by the user for the first time .Users could select foods , input gram counts and have the total calorie count displayed right away.Did we mention that it was more pleasing to the eye? 😉 ,In this tutorial we are going to improve the model of our application and let it save its data in an SQLite database.Along the way ,we ll discuss some practical tips to go by when debugging database applications on the android platform.Continue reading

Android ,Working with Fragments.

android_proud_iconIf you know what an activity is in android ,then you have probably crossed paths with the Fragment concept.The android documentation defines it as a behavior or a portion of user interface in an Activity .It is a stripped down version of an activity that can handle its own lifecycle events but that still needs an activity to host it.I have found a lot of examples that explain how to use fragments but none was focused enough to cover the features I need the most like static fragmentsContinue reading

Android health App Design ,First Steps.

android_studioIn a previous tutorial ,we laid out the design goals for our health android app called RyaNeza.Some people suggested that the name looks ugly on their android screens so I changed the name to Imirire( a noun meaning approximately the act of eating in Kinyarwanda) .This tutorial is about action .We are going to create the project ,get a feel of what is available in Android Studio and explore the optionsContinue reading