Tag Archives: Objective-C

UIPickerView Tutorial — part 2

Before we continue the second installment in the series of basic tutorials about UIPickerView usage and customization, a short digression. Most Cocoa/ Cocoa Touch tutorials assume that all connections to delegates, data sources and outlets are done visually in XCode. Our previous example was no exception. You can see from the project (gave the link below) …

Split NSArray based on characters

Arrays are omnipresent. As I needed a snippet to make a string into an array of values, I thought would be helpful to share this for beginners. For example, take a string variable like, Create an array variable “array1” as:- I used the for loop to know the array1 values, which is displayed in Console …

iOS 7 UIPickerView Simple Application

Recently I was asked by a friend to provide some support with UIPickerView in iOS 7. He was a bit puzzled by what it seemed to be the impossibility to pad the content of each picker view row to a certain distance from the left side of the UIPickerView. Basically, let’s consider the following example. …

Usage of void in C

Going into some USB programming for a project I am into (on my Mac), I ran into this and I thought would be nice and useful to elaborate a bit. This is about void* pointers and callbacks in C. USB device discovery and probing under IOKit makes heavy use of callbacks, I wanted to write …

Chasing Zombies in XCode 4

Ok, this will be a short one. Probably I will create a category like “code snippets and hints” to include all these small articles. This is about zombies in your coding projects and how to chase them. Enabling a project to trace zombies is different in XCode 4 than in previous versions. There is a …

How to use XCode 4 Exception Breakpoints

I will probably write a longer article on exception handling in XCode, for now just a quickie: how to use XCode 4 exception breakpoints, use the breakpoint customization features and get useful information for debugging. Usually when the app is crashing, a lot of cryptical mumbo-jumbo is displayed in the console. You have to dig the …

Core Animation documentation revisited

January brings updated documentation from Apple and I want to share the link to the  completely rewritten Core Animation Programming Guide. The release notes include reference to a “Major revamp, reorganization, and expansion to cover modern Core Animation behavior in iOS and OS X”. Just in time, as some of my projects rely on this. …

Logic Analyzer!

…and not only software (maybe). OK, to keep things short, I got tired by limitations of my Saleae logic analyzer, especially on the software side so I decided to build one. This is my new project: a DIY logic analyzer that I will hopefully use to better extent in my other projects. First results promising. …