2014/10/15 下午 10:13:31

iphone Programming Glossary: roughly

Optimizing CLLocationManager/CoreLocation to retrieve data points faster on the iPhone

http://stackoverflow.com/questions/1081219/optimizing-cllocationmanager-corelocation-to-retrieve-data-points-faster-on-the

fromLocation CLLocation oldLocation if newLocation.horizontalAccuracy 0.0f newLocation.horizontalAccuracy 120.0f roughly an accuracy of 120 meters we can adjust this. myLocs addObject newLocation Thanks for any optimization tricks to speed this..

HTTP Live Streaming, FFMPEG & FFSERVER, and iPhone OS 3

http://stackoverflow.com/questions/1093667/http-live-streaming-ffmpeg-ffserver-and-iphone-os-3

sure you also specify the enable libx264 flag when you're building. Once you've got that up and running you can do roughly the following ffmpeg i input video acodec libmp3lame ac 1 vcodec libx264 s 320x240 level 30 f mpegts segmenter 10 test test.m3u8..

Indoor navigation hardware/software requirements for iOS

http://stackoverflow.com/questions/15732181/indoor-navigation-hardware-software-requirements-for-ios

nodes than Wifi so you might need to deploy some extra nodes for it to be accurate enough. Same accuracy as Wifi roughly 5 meters Dead reckoning uses an accelerometer gyroscope and compass to calculate the speed of heading of the user. Needs..

Pop-up modal with UITableView on iPhone

http://stackoverflow.com/questions/2504478/pop-up-modal-with-uitableview-on-iphone

on iPhone I need to pop up a quick dialog for the user to select one option in a UITableView from a list of roughly 2 5 items. Dialog will be modal and only take up about 1 2 of screen. I go back and forth between how to handle this. Should..

Check if constant is defined at runtime in Obj-C

http://stackoverflow.com/questions/3122177/check-if-constant-is-defined-at-runtime-in-obj-c

but not for constants. iphone objective c cocoa cocoa touch osx share improve this question Jasarien's answer is roughly correct but is prone to issues under LLVM 1.5 where the compiler will optimise the if statement away. You should also be..

iPhone 4 Camera Specifications - Field of View / Vertical-Horizontal Angle

http://stackoverflow.com/questions/3594199/iphone-4-camera-specifications-field-of-view-vertical-horizontal-angle

How to measure distance between two iphone devices using bluetooth?

http://stackoverflow.com/questions/3624945/how-to-measure-distance-between-two-iphone-devices-using-bluetooth

bluetooth you can at best obtain a distance resolution of few meters but you can't calculate the direction not even roughly. You may obtain better results by using multiple bluetooth devices and triangulating the various signal strength but even..

Getting the musical data of an iPod-track

http://stackoverflow.com/questions/3905240/getting-the-musical-data-of-an-ipod-track

ipod share improve this question I haven't done this myself but according to the documentation these are the steps roughly Create an MPMediaQuery to retrieve one or more MPMediaItem objects from the iPod library. Ask those media items for their..

What's the most efficient way of converting a 10 MB JSON response into an NSDictionary?

http://stackoverflow.com/questions/4351930/whats-the-most-efficient-way-of-converting-a-10-mb-json-response-into-an-nsdict

to our backend that provides all the necessary data as a single json response. This results in ~1.5MB compressed or roughly 8 MBs of uncompressed json formatted text. Not much of a problem it downloads in 10 30 seconds and we're using ASIHTTPRequest..

How To Draw line on touch event?

http://stackoverflow.com/questions/4669490/how-to-draw-line-on-touch-event

and a property currentPath of type UIBezierPath . You could then implement the touch detection and drawRect methods roughly like this void touchesBegan NSSet touches withEvent UIEvent event self.currentPath UIBezierPath bezierPath currentPath.lineWidth..

Clearing NSUserDefaults

http://stackoverflow.com/questions/545091/clearing-nsuserdefaults

NSUserDefaults I'm using NSUserDefaults standardUserDefaults to store application settings. This consists of roughly a dozen string values. Is it possible to delete these values permanently instead of just setting them to a default value..

If you have an IBOutlet, but not a property, is it retained or not?

http://stackoverflow.com/questions/5523290/if-you-have-an-iboutlet-but-not-a-property-is-it-retained-or-not

or retains the object by default if no setter method is available. The default behavior of setValue forKey in iOS is roughly lazy pseudocode if self respondsToSelector @selector @ setKeyName self setKeyName value else object_setIvar self _keyName..

Background GPS in iOS. Is this possible?

http://stackoverflow.com/questions/5526403/background-gps-in-ios-is-this-possible

recommended by Apple 㽘ses less power at the cost of accuracy this blog post indicates that the updates are accurate to roughly 500m while the latter is as accurate as the device can manage. This is all detailed in the iOS Application Programming Guide..

How can I optimize the rendering of a large model in OpenGL ES 1.1?

http://stackoverflow.com/questions/5718846/how-can-i-optimize-the-rendering-of-a-large-model-in-opengl-es-1-1

I optimize the rendering of a large model in OpenGL ES 1.1 I just finished implementing VBO's in my 3D app and saw a roughly 5 10x speed increase in rendering. What used to render at 1 2 frames per second now renders at 10 11 frames per second...

Warning in Custom Map Annotations iPhone

http://stackoverflow.com/questions/5872547/warning-in-custom-map-annotations-iphone

Why is UIBezierPath faster than Core Graphics path?

http://stackoverflow.com/questions/6327817/why-is-uibezierpath-faster-than-core-graphics-path

one UIBezierPath and one CGPath. The paths are identical except for their locations but stroking the CGPath takes roughly twice as long as stroking the UIBezierPath. void drawRect CGRect rect CGContextRef ctx UIGraphicsGetCurrentContext Create..

How does one compare one image to another to see if they are similar by a certain percentage, on the iPhone?

http://stackoverflow.com/questions/6488732/how-does-one-compare-one-image-to-another-to-see-if-they-are-similar-by-a-certai

use case repeatedly querying the same image but it should provide a good starting point. Then you can use an algorithm roughly like float numDifferences 0.0f float totalCompares width height 100.0f for int yCoord 0 yCoord height yCoord 10 for int..

How to compare a shape drawn on the screen to a letter?

http://stackoverflow.com/questions/7990774/how-to-compare-a-shape-drawn-on-the-screen-to-a-letter

a bezier path from a glyph or you may have to design them yourself. You then need to scale the bezier path so it is roughly the same size as the drawing on the screen. Then check how many of the points in the drawn path fall within your standard..

Flurry events not showing up at all

http://stackoverflow.com/questions/9821996/flurry-events-not-showing-up-at-all

with your login credentials and wait for some more hours. Moreover it is not real time service as far as I know. It roughly takes 6 8 hours to show the logged results. Otherwise you need to contact Flurry Analytics guys as it is really a simple..