Mobile & web development
I had a file that was edited in Windows, so it had CRLF line breaks. It was a script and I had to change the line breaks to LF before I could run the script in bash. I converted the line breaks to Unix style using the vi editor and…
I was implementing an Apple Pay functionality for a website and one of the requirements was that the server must support the Transport Layer Security (TLS) 1.2 protocol. There was an easy way to check that from MacOS command line. openssl s_client -connect example.com:443 -tls1_2 I got a certificate chain…
Vapor defaults to port 8080 on localhost. I couldn’t use the 8080, since that was reserved for another server on my MacBook Pro. Here’s how I set a different port number from the command line. swift run Run –hostname localhost –port 9000 This works with Vapor Framework 3.0.8 and Toolbox…
Getting the user’s browser window size is super easy to do with jQuery. Just a simple one line of code gives us a width or height value. var width = $(window).width() var height = $(window).height() However there’s one caveat. If we are running this code while the user is resizing…
A counting semaphore is a way of controlling access to a resource from multiple contexts. It can be also a solution for handling asynchronous methods in command line utilities. I was making a command line utility to access REST APIs recently. I needed a way to make sure that the…
It just happens sometimes. The UI responds to a button touch, but then it just freezes. Nothings happens in the UI. CPU runs with maximum speed and the amount of used memory increases constantly. Our code is in an infinite loop and we’ll need to find out why. There is…
Progress bar is a nice way of showing users that our app is downloading content and things are progressing. The progress bar can be placed anywhere on the screen, but it is usually a thin line just under the navigation bar. We can create a progress bar programmatically and set…
My go to solution for a web view is WKWebView. It can be fully customized to fit the look and feel of my app. I can run JavaScript inside of it and enjoy the good performance. Why should I use anything else? UIWebView is the older way of integrating web…
Most of the apps that I build require some kind of back-end solution. A key task for this server side code is often to write data to a database. There are many different flavors of databases and server side languages. Here’s an example using PHP and MySQL.
When we work with auto layout we will hit an unsatisfiable constraint error at some point. The result is a view that looks somehow broken and there are a lot of text in the Xcode’s debugger window. The unsatisfiable constraint error means that there are some conflicting constraints and the…