Posts - page 9

Recent posts

Unit testing asynchronous Android network libraries

January 01, 2020  5 minute read  

I’m writing a network library for Android at the moment, and specifically looking at unit tests. In my last article, I looking at mocking the Android context and other Android specific libraries. Since I am writing a network client library, I need to go a step further and deal with the network connection itself. How can I test the asynchronous network calls in a repeatable manner? Fortunately, there’s a library for that. Square, the same people that brought you OkHttp, also produce a moc...

Two tips for unit testing Android libraries

December 24, 2019  3 minute read  

I’m busy writing a networking library for one of my Android apps. The question today is “how do I properly test the library?” There are a few problem areas, and I’ll cover two of them today. How do I properly mock classes that aren’t really Android specific, like android.location.Location and android.net.Uri? How do I properly mock the Android context? Android Studio already integrates the excellent JUnit packages for unit testing. I don’t want to have to write a visual app just to...

Build a better RecyclerView Adapter

December 13, 2019  3 minute read  

Many of my Android apps end up including listst, which are implemented via a RecyclerView. More importantly, I know all the items in the list ahead of time. Every single blog and tutorial always uses the same methodology. This ends up being a lot of boilerplate code. Create a view holder class Create a list adapter Attach the list adapter to the recyclerview Update the view holder class to implement the UI Check out the requirements around clicking Arrange for the list of item...

Handle location and geocoding with SwiftUI

November 05, 2019  5 minute read  

I’m continuing on my Weather app research in SwiftUI. My next problem is this: How do I get the current location (as a longitude / latitude) and a place (like a city) in my app such that the UI is updated when location updates happen? It turns out that this is a fairly easy problem, but it does come with some knowledge that you just have to know. Here is the list: How can I update the UI based on programmatic changes to the value? How can I listen for location updates? How can I c...

Create a bubble background in SwiftUI

November 02, 2019  3 minute read  

I’m continuing to explore SwiftUI, trying to recreate user interfaces that I see on design labs. The latest one is a task list app, found on Uplabs, and created by Rudi Hartano. I liked the design so I decided to replicate it from the Adobe XD file that he provided. One of the pieces he uses is a bubble background: The Adobe XD file shows me that I can use a linear gradient between two colors. However, there are also two slightly translucent circles on the top of it. If I were in Andr...

Why SwiftUI might just convert me to an iOS developer

October 31, 2019  9 minute read  

Confession time. I hated iOS development. First, there was Objective-C (which was a nightmare of epic proportions for cryptic syntax), then there was the Storyboards. Both of them forced you into using what is quite possibly the worst IDE on the market today (XCode), all so you could fit into the Apple ecosystem walled garden, where everything is controlled. Then Swift came along, so I took another look. I loved the direction that Swift was going, but Storyboards and the unintuitive IDE ...

Deploying an Azure Function App with Terraform

October 23, 2019  7 minute read  

You may have caught this from my previous blog posts, but I like automated deployments. I like something where I can run one command and magic happens, resulting in my whole deployment changing to a new state. I’ve recently been looking around at options for Azure, checking out Serverless Framework, Azure Resource Manager (ARM), and others. My favorite thus far has been Terraform. These are the instructions for deploying a basic Azure Function app with TypeScript code from start to finish...

Validating permissions on Android with Kotlin

October 07, 2019  2 minute read  

I’m continuing my educational coding exercise, developing a new photo sharing app. Recently, I completed my user authentication and registration process and I’m now quite happy with it, so I moved on to taking photographs. I’ve got an activity with a toolbar and a floating action button: <?xml version="1.0" encoding="utf-8"?> <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/r...

Using Azure App Configuration for Remote Config with Android

September 22, 2019  11 minute read  

I’ve been playing with a new app recently. I decided I needed some support from the cloud around feature flags (turning on and off features for specific people so I can test things) and for remote configuration. Fortunately, Azure has a service in preview - App Configuration - and it does both of these things. There are preview libraries to go along with it for .NET, Java 8, JavaScript, and Python. Sadly, there is no library for Android Java. Fortunately, we can fix that! Let’s take a l...

Building an efficient Logger in TypeScript

June 30, 2019  6 minute read  

Just about every project needs a logging system. In the early days of development, you need to output data to the console so you aren’t setting breakpoints in your code all over the place (or you are running the code in the browser, where breakpoints are more difficult). Later on, you want logging to let you know where people are spending their time, or how much usage a particular feature gets. It also helps with diagnosing problems early so that you can get ahead of the issues. There are...