Top "Objective-c" questions

This tag should be used only on questions that are about Objective-C features or depend on code in the language.

Left Align Cells in UICollectionView

I am using a UICollectionView in my project, where there are multiple cells of differing widths on a line. According …

ios objective-c uicollectionview uicollectionviewlayout
What is autoreleasepool?

Possible Duplicate: Why use Autorelease pool? All Objective-C starting page opens with a default @autoreleasepool{...} statement under the main function …

objective-c object release autorelease nsautoreleasepool
Error "No known class method for selector 'Hello:'" in custom-made framework

I am making a framework for a company and I have completed all the code. I'm now trying to package …

objective-c ios cocoa-touch compiler-errors ios-frameworks
How to add one month to an NSDate?

How To Add Month To NSDate Object? NSDate *someDate = [NSDate Date] + 30Days.....;

ios iphone objective-c nsdate
NSLog the method name with Objective-C in iPhone

Currently, we are defining ourselves an extended log mechanism to print out the class name and the source line number …

objective-c c iphone debugging
Overriding init in subclass

In Objective-C, is it necessary to override all inherited constructors of a subclass to add custom initialization logic? For example, …

objective-c inheritance uiview initialization init
NSInvocation for Dummies?

How exactly does NSInvocation work? Is there a good introduction? I’m specifically having issues understanding how the following code (…

objective-c cocoa undo-redo
UICollectionView and Supplementary View (header)

Trying to add a a Supplementary view into my UICollectionView as a header. I'm having issues getting it to work. …

ios objective-c uicollectionview uicollectionviewlayout
Create a UIImage with a URL in iOS

To create an UiImage with a image file, I use the code as below: UIImage *aImage = [[UIImage imageNamed:@"demo.jpg"]…

objective-c ios uikit uiimage
How can I get rid of an "unused variable" warning in Xcode?

I understand exactly why unused variable warnings occur. I don't want to suppress them in general, because they are incredibly …

objective-c xcode compiler-warnings unused-variables