Captain Danko’s JavaScript Lab — Code Smarter with Tutorials, Frameworks & Dev Insights

In part 1 , I gave a brief, very high level overview on how Java web apps are written. Ok how about a quick recap of what was covered in part 1...actually let's use some diagrams this time. Previously ... in Part 1 Java web app architecture The above diagram essentially summarises what was written in the section titled " Java web app walkthrough", so in a nutshell For a Java web app, the user interface (UI) is created via HTML/CSS/Javascript The Controllers i.e. Java code act as a communication layer between the UI and the Data store, typically a Database: what that means is that the Java code passes data to and from the UI and the Data Store(Database). The kind of Data Store that I normally work with is a  relational database , there is a reason I have mentioned the type of database, read on to find out why. Refer to Part 1 for a more detailed walkthrough of a real-world example of using a registration form Now how can we apply the above approach to w...

One of the outcomes of my work on my first iOS app is my Github repository Html5StarterAppWithSwift which is an Xcode project template for creating Html5/iOS apps, or maybe we can call it "native Html5 iOS apps"... hmm what do I mean? What I mean is, it's an Xcode project template, that can help you create native iOS apps such that all of the app's UI is powered by Html/Javascript, while it makes use of native iOS code ( Swift ) for scheduling local notifications, storing data ( Core Data ) etc. p.s. if you would like to know about Html5StarterAppWithSwift , you can have a read of this post . So what is this post about? I have a background in writing  Java  web apps i.e. for my day job, I write Java web apps using frameworks such as Struts , Play  etc and there is a way in which those Java web apps are written. Now, when I started working on my first iOS app, my Java developer background played a big part in the way I structured my app i.e. separation of code...

In this post , I shed some light on the background and the circumstances leading upto my App( iOS ) and in this post, I will talk about when I first got the idea and for the App i.e. App Inception and my recovery. So for those who have not read part 1 of the series, basically what happened was, I am a Software engineer who lived a pretty good life, until one day I was a victim of a hit and run car accident. I was a pedestrian crossing the road, when a drunk driver ran a red light and hit me, left me for dead and ran away. I was eventually rescued by the paramedics and amongst other things, I suffered from a Traumatic brain injury and things fell apart. There is tragedy in my story, even though it's not quite like Okonkwo's story , it's tragedy none the less and my story is still going and good things are starting to happen. App inception So as I said, few months post injury, I had a break-up with my now ex-girlfriend, what that meant was that my family had to live...

So before I write part 2 of the story of how my first mobile( iOS ) app came to be, this would be a small post on how to use Extensions in Swift, to make code more readable...amongst other things. Problem So in my iOS app, there are a few places where I have to get the day before(yesterday) and the day after(tomorrow) for a date.  Solution In the first version of my code, I had the code such as this (Read on to find out a more correct solution for calculating dates) For the day after let oneDay:Double = 60 * 60 * 24 return self.dateByAddingTimeInterval(oneDay) For the day before let oneDay:Double = 60 * 60 * 24 return self.dateByAddingTimeInterval(-(Double(oneDay))) one day has 24 hours, each hour has 60 mins and each minute has 60 seconds, so 60 * 60  * 24 to calculate the solution to my problem. This was working and it was all fine...until I delved deeper into Swift(by reading this  ebook  by Apple) and found out about Extensions!!! It ...

So I have made references to my iOS app in a lot of my previous posts, if you refer to my post on Why can't I cancel a local notification in my iOS app? (in Swift) , it mentions some of the posts that I have written on how I have solved some of the problems that I have come across. It's been a year since I have been working on the app and now that I am close to finishing it, I thought I would write a little bit about the background of how this app came to be. Prelude: the land of blue skies and sunshine The year was 2013 and these were some of the key aspects of my life, I was a bit of a fast talker and people often told me, my English ascent was pretty flat for a man from India I kept fit and I did regular runs with each run being over 8-10 km I had a very loving girlfriend and we had plans to get engaged to be married in 2014 I had a job that I loved and enjoyed After years of living in a place sharing with flatmates and all, I was finally living in my own apart...

Ok for iOS devices I think it will still be at least another year, till we have devices that are using versions earlier than iOS 8 ! so what does that mean? Problem Well, it means that if we are building an iOS app that works on both iOS 7 and 8 which uses a feature introduced in iOS 8, we need to check if that feature exists on the device before using it. Now the iOS app that I am building uses local notifications and in iOS 8 Apple introduced this feature to ask the user to receive LOCAL NOTIFICATIONS via   registerUserNotificationSettings . So what I wanted to do is check if the feature exists on the device the app is running on without checking the iOS version on the device via  UIDevice.currentDevice().systemVersion . Solution So turns out NSObject has this really useful method called instancesRespondToSelector , so I can solve my problem of finding out the presence of registerUserNotificationsSettings using the following code, UIApplication.instancesRespon...

So my first iOS  app is nearly complete; by nearly complete, I mean it is a working app that I am using on a daily basis. I plan to use it for another two weeks or so, and see if can break any app feature in my daily usage. This is also a time when I have added every major feature to the app and what I do from time and again these days is a minor UI fix or optimise some of my earlier iOS code. You see, I started working on this app over a year ago and in that time, my knowledge of iOS programming has grown, I know more now, and I often find myself realising that there is certain code in my app that could be better written. So I go ahead with the re-write if it is nothing too major. One potential risk/side-effect of a minor UI fix or code optimisation is that I often end up breaking other app features. What have I learned? Well at this point I realise that had I written a bunch of unit tests in the beginning, testing the app after every minor fix or optimisation would have bee...