2014/10/15 下午 10:13:19

iphone Programming Glossary: representing

http://stackoverflow.com/questions/10049533/correcting-floating-point-numbers

only have so many bits to use so they quickly run out and have to round to the nearest value that they are capable of representing. Typically you don't worry about the .0000001 and just format them when you want to display them to the user with the appropriate..

iOS: Get pixel-by-pixel data from camera

http://stackoverflow.com/questions/10865100/ios-get-pixel-by-pixel-data-from-camera

CVPixelBufferGetBaseAddress on that pixel buffer will return the base address of the byte array for the raw pixel data representing your camera frame. This can be in a few different formats but the most common are BGRA and planar YUV. I have an example..

How to draw a MKPolyline on a MapView?

http://stackoverflow.com/questions/10911534/how-to-draw-a-mkpolyline-on-a-mapview

coordinates count numberOfSteps map addOverlay polyLine where map is an instance of MKMapView and path the array representing the already decoded set of points. I thought that with the line map addOverlay polyLine it would be drawn. I've seen in..

Number of days in the current month using iPhone SDK?

http://stackoverflow.com/questions/1179945/number-of-days-in-the-current-month-using-iphone-sdk

NSRange days c rangeOfUnit NSDayCalendarUnit inUnit NSMonthCalendarUnit forDate today today is an NSDate object representing the current date this can be used to work out the number of days in the current month. An NSCalendar object is then instantiated..

iOS and finding Tomorrow

http://stackoverflow.com/questions/12681989/ios-and-finding-tomorrow

iphone share improve this question Using NSDateComponents you can extract day month year components from the date representing today ignoring the hour minutes seconds components add one day and rebuild a date corresponding to tomorrow. So imagine.. date corresponding to tomorrow at midnight you could instead just retrieve the month day year components of the date representing now without hours min secs part and add 1 day then rebuild a date Decompose the date corresponding to now into Year Month..

Best way to serialize a NSData into an hexadeximal string

http://stackoverflow.com/questions/1305225/best-way-to-serialize-a-nsdata-into-an-hexadeximal-string

share improve this question This is a category applied to NSData that I wrote. It returns a hexadecimal NSString representing the NSData where the data can be any length. Returns an empty string if NSData is empty. NSData Conversion.h #import Foundation..

AES Encryption for an NSString on the iPhone

http://stackoverflow.com/questions/1400246/aes-encryption-for-an-nsstring-on-the-iphone

Detecting current iPhone input language

http://stackoverflow.com/questions/1414876/detecting-current-iphone-input-language

currently being used for text input. UITextInputMode currentInputMode .primaryLanguage will give you an NSString representing the BCP 47 language code such as 𩃀s 𩃀n US or 𠨑r CA You can register for the UITextInputCurrentInputModeDidChangeNotification..

Objective-C: Best way to access REST API on your iphone

http://stackoverflow.com/questions/1557040/objective-c-best-way-to-access-rest-api-on-your-iphone

recommend checking out RestKit http restkit.org It provides an excellent API for accessing RESTful web services and representing the remote resources as local objects including persisting them to Core Data. HTTP authentication is supported out of the..

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

c datetime sqlite share improve this question In SQLite there is no date time column type per se so one ends up representing dates either as Julian date values real columns or in strings text columns . SQLite is also very particular in how dates..

Objective C parse hex string to integer

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

C parse hex string to integer I would like to know how to parse a hex string representing a number in objective c. I am willing to use both an objective or a C based method either is fine. example #01FFFFAB should..

Get PDF hyperlinks on iOS with Quartz

http://stackoverflow.com/questions/4080373/get-pdf-hyperlinks-on-ios-with-quartz

on each page use CGPDFDictionaryGetArray pageDictionary Annots outputArray where pageDictionary is the CGPDFDictionary representing the CGPDFPage and outputArray is the variable CGPDFArrayRef to store the Annots array of that page in. share improve this..

Basic Drag and Drop in iOS

http://stackoverflow.com/questions/4707858/basic-drag-and-drop-in-ios

drop. What do you think is the best large scale strategy for doing this Is it best to get touch events from the views representing the vehicles or from the larger view Is there a simple paradigm you've used for drag and drop that you're satisfied with..

Change name of iPhone app in Xcode 4

http://stackoverflow.com/questions/5043066/change-name-of-iphone-app-in-xcode-4

will help everyone 1.In the project contents pane at left click the Folder icon. 2.Select the top level blue line representing the project. 3.If you don't have the Inspector pane right pane open click the button to enable it. This is the third button..

NSNumber vs Int

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

Details The ObjC runtime will in some cases on some architectures and on some OS versions substitute a tagged pointer representing NSNumber s of specific type and domain. Although the internal representation has changed since originally written a few.. you from slow operations like allocations locking and ref count ops. Nevertheless tagged pointers are incapable of representing every number and it introduces overhead so you should still favor basic builtins over NSNumber as a default. Tagged pointers..

Create custom keyboard and configure it on your iPhone

http://stackoverflow.com/questions/7189287/create-custom-keyboard-and-configure-it-on-your-iphone

Get NSDate from NSDate adjusted with timezone

http://stackoverflow.com/questions/7485493/get-nsdate-from-nsdate-adjusted-with-timezone

00 00 00 That date translates into 2011 09 30 22 00 00 because of my timezone. Question How do I get a new Date object representing 2011 10 01 00 00 00 in my local timezone iphone ios timezone nsdate locale share improve this question NSDate only.. NSDate date calendar dateFromComponents timeZoneComps At this point date stores the exact point in time in seconds representing the current calendar. 2. NSDate output using NSDateFormatter For a controlled output of your NSDate you need NSDateFormatter..