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.

checking if an array doesn't contain a certain object

is there a class available to check if an array doesn't contain an object? I want to do something like …

objective-c nsarray
How to compare UIColors?

I'd like to check the color set for a background on a UIImageView. I've tried: if(myimage.backgroundColor == [UIColor greenColor]){ ...} …

ios objective-c cocoa-touch uiimageview uicolor
What's the difference between #if and #ifdef Objective-C preprocessor macro?

How to define preprocessor macros in build settings, like IPAD_BUILD, and IPHONE_BUILD (and how to use them in …

ios objective-c macros c-preprocessor conditional-compilation
How can I create a custom UIActivity in iOS?

How can I create a custom UIActivity in iOS? The reason I want this is to add a Review App …

ios objective-c uiactivityviewcontroller uiactivity
Scale UIView and all its children

I have an UIView with around 50 UIButtons. All button positions were given in pixels, relative to the left upper corner …

ios objective-c uiview scale subview
How can I get the first element in an NSDictionary?

I have an array of NSDictionaries. How can I pull out the first element in the dictionary? NSArray *messages = [[results …

iphone objective-c cocoa cocoa-touch nsdictionary
display done button on UIPickerview

I have written the following code in the viewDidLoad method: categoryPickerView=[[UIPickerView alloc]init]; categoryPickerView.alpha = 0; [self.view addSubview:categoryPickerView]; …

ios objective-c uipickerview
String to CLLocation latitude and Longitude

I have two strings representing latitude and longitude like: "-56.6462520", and i want to assign then to a CLLocation object …

iphone objective-c string cllocation
Expanding and Collapsing table view cells in ios

I have a table view of custom cells and some buttons in each cell.Clicking on any of the button …

ios objective-c uitableview customization
Sound not working in iPhone Simulator?

Somehow my iPhone Simulator is unable to play sounds. First an app I'm working on using AudioServicesPlaySystemSound() stopped working.. I …

iphone objective-c cocoa-touch audio ios-simulator