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.

Remove HTML Tags from an NSString on the iPhone

There are a couple of different ways to remove HTML tags from an NSString in Cocoa. One way is to …

ios objective-c iphone cocoa-touch nsstring
NSDictionary - Need to check whether dictionary contains key-value pair or not

I just need to ask something as follow. Suppose I am having a dictionary. NSMutableDictionary *xyz=[[NSMutableDictionary alloc] init]; [xyz …

ios objective-c nsdictionary
Convert to absolute value in Objective-C

How do I convert a negative number to an absolute value in Objective-C? i.e. -10 becomes 10?

objective-c
Detecting iOS orientation change instantly

I have a game in which the orientation of the device affects the state of the game. The user must …

iphone objective-c ios orientation gyroscope
What's the difference between using CGFloat and float?

I tend to use CGFloat all over the place, but I wonder if I get a senseless "performance hit" with …

iphone objective-c cocoa-touch
Changing Font Size For UITableView Section Headers

Can someone please instruct me on the easiest way to change the font size for the text in a UITableView …

ios objective-c swift uitableview uitableviewsectionheader
'Invalid update: invalid number of rows in section 0

I've read all of the related posts regarding this and I am still having an error: 'Invalid update: invalid number …

ios objective-c arrays nsmutablearray
How to define a preprocessor symbol in Xcode

Is it possible to set a symbol for conditional compilation by setting up properties in an Xcode project? My aim …

objective-c xcode c-preprocessor
How to make URL/Phone-clickable UILabel?

I want to create a clickable label on my app leading me to a Safari webpage. I also want the …

iphone objective-c url uilabel
What is the Swift equivalent of respondsToSelector?

I've googled but not been able to find out what the swift equivalent to respondsToSelector: is. This is the only …

objective-c swift selector