The Big Picture ObjC is OOP which means objects send messages to other objects. Before getting into messages, let’s define objects. Objects. This is very diverse. An object can be a string, a number, a Boolean, an integer, an array, a dictionary or even one you create yourself. There are any types of objects but let’s start at the root object. The root object is called NSObject. You’ll see references to it in code but you’ll hardly ever use it directly. This is called the root object because it’s the starting point of any object. It’s like Adam and Eve rolled into one and ANY other kind of object in… Read More
Continue ReadingGrandCentralDispatch & Blocks
GCD helps improve your apps performance and responsiveness by outsourcing processes that require a lot or computing power to the background while keeping your UI responsive. Normally you might want to do some heavy lifting. Let’s create an Empty Application. You need to declare a IBOutlet UIImageView *imageView ivar in your appDelegate, make it a property and synthesize it in .m and make the connection in Interface Builder, IB. In it’s viewDidLoad method put the following code: // Download the image NSURL *url = [NSURL URLWithString:@”http://www.santiapps.com/assets/bbkoko.jpg”]; NSURLRequest *req = [NSURLRequest requestWithURL:url]; NSURLResponse *res = [[NSURLResponse alloc] init]; NSError *err = nil; NSData *data = nil; data = [NSURLConnection sendSynchronousRequest:req returningResponse:&res… Read More
Continue ReadingHow to Read iOS or Mac OS Programming Documentation
The toughest part for me to get started was reading the Apple Documentation on iOS or MacOS. When I got into more APIs it got more complex. You need to understand how to read API or proprietary code documents in order to understand how to create a piece of code, connect to web services or debug changes in code. You will very often see the term DEPRECATED, which means a particular method name is no longer used. This is very important so let’s take a look at Apple Docs first: This tells us that the object of type NSArray has many methods that you can call on it. They may… Read More
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