2014/10/15 下午 10:10:30

iphone Programming Glossary: integers

What's the difference between NSNumber and NSInteger?

http://stackoverflow.com/questions/1285098/whats-the-difference-between-nsnumber-and-nsinteger

this question The existing answers are useful adding to them Yes NSUInteger gives twice the range among positive integers as NSInteger but I think another critical reason to choose between the two is simply to distinguish among cases where negative..

How get a datetime column in SQLite with Objective C

http://stackoverflow.com/questions/1711504/how-get-a-datetime-column-in-sqlite-with-objective-c

with Objective C I have a table with 4 fields pk datetime value1 and value2 . pk primary key value1 and value2 are integers so I am using int value1 sqlite3_column_int statement 2 int value1 sqlite3_column_int statement 3 But what should I use..

Possible to save an integer array using NSUserDefaults on iPhone?

http://stackoverflow.com/questions/350848/possible-to-save-an-integer-array-using-nsuserdefaults-on-iphone

using NSUserDefaults on the iPhone I have an array declared in my .h file as int playfield 9 11 that gets filled with integers from a file and determines the layout of a game playfield. I want to be able to have several save slots where users can..

Objective C parse hex string to integer

http://stackoverflow.com/questions/3648411/objective-c-parse-hex-string-to-integer

this question Joshua Weinberg's answer is mostly correct however the Ox prefix is optional when scanning hexadecimal integers. If you have a string in the format #01FFFFAB you can still use an NSScanner but you can simply skip the first character...

Creating UIImage from raw RGBA data

http://stackoverflow.com/questions/4545237/creating-uiimage-from-raw-rgba-data

been trying to convert an array RGBA data int bytes into a UIImage. My code looks like as follows height and width are integers denoting the dimensions of the image unsigned char rawData malloc width height 4 for int i 0 i width height i rawData 4.. out the problem is a pretty silly mistake that both of us overlooked. UIImage dimensions are stored as floats not integers. D Try NSLog @ resultImg width f height f newImage.size.width newImage.size.height Instead. The image size has been transferred..

Sort an NSMutableDictionary

http://stackoverflow.com/questions/4558639/sort-an-nsmutabledictionary

I have an NSMutableDictionary that maps NSString to NSString although the values are NSStrings they are really just integers . For example consider the following mappings dog 4 cat 3 turtle 6 I'd like to end up with the top 10 entries in the dictionary..

TextField Validation With Regular Expression

http://stackoverflow.com/questions/5765654/textfield-validation-with-regular-expression

Regular Expression I need help with code that looks at a textfield make sure it starts with either a or then has 3 integers after it. So valid data looks like 234 or 888 So I have started this code but there are 2 problems with it It correctly..

Getting RGB pixel data from CGImage

http://stackoverflow.com/questions/6073259/getting-rgb-pixel-data-from-cgimage

data from CGImage I am trying to access pixel data from a CGImage. I want to be able to access the RGB values as integers. I think I am nearly there with this code UIImage theImage UIImage imageNamed @ rgb.png CGImageRef cgImageRef CGImageRetain..

iOS: How do I generate 8 unique random integers?

http://stackoverflow.com/questions/6153550/ios-how-do-i-generate-8-unique-random-integers

How do I generate 8 unique random integers I need to generate 8 random integers but they need to be unique aka not repeated. For example I want 8 numbers within the.. How do I generate 8 unique random integers I need to generate 8 random integers but they need to be unique aka not repeated. For example I want 8 numbers within the range 1 to 8. I've seen arc4random..

NSNumber vs Int

http://stackoverflow.com/questions/6662730/nsnumber-vs-int

vs Int If integers cannot be written to a dictionary and then a plist but NSSNumbers can. Is it better to use NSNumbers throughout the app.. good introduction to the subject http objectivistc.tumblr.com post 7872364181 tagged pointers and fast pathed cfnumber integers in . Where this can be used it saves you from slow operations like allocations locking and ref count ops. Nevertheless tagged..

Is programmatically inverting the colors of an image possible?

http://stackoverflow.com/questions/6672517/is-programmatically-inverting-the-colors-of-an-image-possible

exposition to should do the trick @implementation UIImage NegativeImage UIImage negativeImage get width and height as integers since we'll be using them as array subscripts etc and this'll save a whole lot of casting CGSize size self.size int width.. channel if it isn't zero of course to get uninflected RGB. We multiply by 255 to keep precision while still using integers int r g b if linePointer 3 r linePointer 0 255 linePointer 3 g linePointer 1 255 linePointer 3 b linePointer 2 255 linePointer..

How to record sound produced by mixer unit output (iOS Core Audio & Audio Graph)

http://stackoverflow.com/questions/7118429/how-to-record-sound-produced-by-mixer-unit-output-ios-core-audio-audio-graph

see what the samples look like. If the callback is receiving 16 bit audio the samples should be positive or negative integers between 32000 and 32000. If the samples alternate between a normal looking number and a much smaller number try this code..

iOS Stream Audio from one iOS Device to Another

http://stackoverflow.com/questions/8357514/ios-stream-audio-from-one-ios-device-to-another

of the data you receive matches exactly. Checkout things like number of channels mono or stereo number of frames integers or floats and sample rate. If anything doesn't match up you'll either get EXC_BAD_ACCESS errors as you work your way through.. of data either an integer or a float. Mono or stereo you have one or two channels in a frame. That defines how many integers or floats are in that frame. Then you have frames per packet probably 1 . Your sample rate determines how many of those..