2014/10/15 下午 10:12:24

iphone Programming Glossary: overhead

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

contain 64.1 NSDecimalNumber will take care of all of this for you but it a little more involved and involves more overhead but here's an example to get you started NSDecimalNumber num1 NSDecimalNumber decimalNumberWithString @ 32 NSDecimalNumber..

Core Data vs Sqlite and performance

http://stackoverflow.com/questions/1045238/core-data-vs-sqlite-and-performance

Data in the 3.0 SDK. I suspect that under the hood Core Data is just using sqlite anyways and that it add's a bit of overhead for the cost of convenience but i thought i would ask anyways. iphone cocoa touch core data share improve this question..

How to check for an active Internet Connection on iPhone SDK?

http://stackoverflow.com/questions/1083701/how-to-check-for-an-active-internet-connection-on-iphone-sdk

check to see for a response from some other websites if Google didn't respond it does seem wasteful and an unnecessary overhead on my application. BOOL connectedToInternet NSString URLString NSString stringWithContentsOfURL NSURL URLWithString @ http..

What does the Tiler Utilization statistic mean in the iPhone OpenGL ES instrument?

http://stackoverflow.com/questions/1287811/what-does-the-tiler-utilization-statistic-mean-in-the-iphone-opengl-es-instrumen

additional draw calls but I suspect the improvement in vertex throughput will outweigh the extra per draw call CPU overhead. Note that it 䏭 generally beneficial on MBX and elsewhere to ensure that each vertex attribute begins on a 32 bit boundary..

Use CoreData or SQLite on iPhone? [closed]

http://stackoverflow.com/questions/1318467/use-coredata-or-sqlite-on-iphone

very significant performance benefits particularly on the iPhone. Even though it seems counterintuitive given how much overhead you'd think the framework has in most cases you can beat the performance of hand tuned SQLite using Core Data. On the iPhone..

What is the right choice between NSDecimal, NSDecimalNumber, CFNumber?

http://stackoverflow.com/questions/1704504/what-is-the-right-choice-between-nsdecimal-nsdecimalnumber-cfnumber

I also understand that I should use NSDecimalNumber but there is two things that I would like to know Are the memory overhead and performance loss acceptable for a somewhat more complicated class only financial computations of this kind showed in.. is the right choice for you. To answer your questions only testing of your code can reveal whether the memory overhead and performance loss are acceptable to you. I haven't really worked much with NSDecimalNumber but I'd wager that Apple's..

How can my iPhone Objective-C code get notified of Javascript errors in a UIWebView?

http://stackoverflow.com/questions/193119/how-can-my-iphone-objective-c-code-get-notified-of-javascript-errors-in-a-uiwebv

is still eluding me. NOTE after posting this I did find one way using a debugging delegate. Is there a way with lower overhead using the error console web inspector iphone objective c webkit share improve this question I have now found one way..

Is garbage collection supported for iPhone applications?

http://stackoverflow.com/questions/416108/is-garbage-collection-supported-for-iphone-applications

objective c cocoa touch ios garbage collection share improve this question No. Garbage collection is too large an overhead for the limited battery life etc. on the device. You must program always with an alloc release pattern in mind. NSXMLParser..

Send and receive NSData via GameKit

http://stackoverflow.com/questions/4837102/send-and-receive-nsdata-via-gamekit

like endian ness etc. The tricky part of the packetizing process using NSCoding is that you don't really know what the overhead of the coding process is so being as big as possible but still under the max packet size is tricky... I present this without.. you want a decent start on that approach this may be it. Be warned I didn't check to see if my arbitrary 100 bytes for overhead was realistic. You'll have to play with the numbers a little bit. Packet.h @interface Packet NSObject NSCoding NSString..

NSMutableString as retain/copy

http://stackoverflow.com/questions/4995254/nsmutablestring-as-retain-copy

clear and not very considerate for clients. it also implies a lot of unnecessary things and introduces additional copy overhead. let's re evaluate this. additional considerations problems at this point the default setter requires that the client makes..

Creating a JSON Store For iPhone

http://stackoverflow.com/questions/5237943/creating-a-json-store-for-iphone

is simple then SQL can handle even highly volatile data efficiently. If the UI is equally simple then there is little overhead in integrating the UI into the object oriented design of an iOS MacOS app. 3 As the data grows more complex Core Data quickly.. highly intelligent caching. Also don't confuse I understand SQL thoroughly but not Core Data with Core Data has a high overhead. It really doesn't. Even when Core Data isn't the cheapest way to get data in and out of persistence it's integration with..

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

colored vertices and render them as one group at a set color rather than supplying per vertex color information. The overhead from the few extra draw calls this requires will be vastly outweighed by the speedup you get from not having to send all..

What's the best approach to draw lines between views?

http://stackoverflow.com/questions/5847876/whats-the-best-approach-to-draw-lines-between-views

animating start end points width color alpha ... There's an easy way to do this completely avoiding the described overhead Use a CALayer for your line but instead of redrawing the contents on the CPU just fill it completely with the line's color..

Why is autorelease especially dangerous/expensive for iPhone applications?

http://stackoverflow.com/questions/613583/why-is-autorelease-especially-dangerous-expensive-for-iphone-applications

autorelease carefully not avoiding it altogether. and now for my comment It sounds like there is a certain amount of overhead in maintaining the pool. I read this article which would lead me to probably avoid autorelease as much as possible because..

Are the Core Image filters in iOS 5.0 fast enough for realtime video processing?

http://stackoverflow.com/questions/6625888/are-the-core-image-filters-in-ios-5-0-fast-enough-for-realtime-video-processing

to determine if your particular device could handle this processing at a decent framerate. Core Image may add a little overhead but it also has some clever optimizations for how it organizes filter chains. The slowest compatible devices out there would..

Correct Singleton Pattern Objective C (iOS)?

http://stackoverflow.com/questions/7598820/correct-singleton-pattern-objective-c-ios

some information in the net to create a singleton class using GCD. Thats cool because it's thread safe with very low overhead. Sadly I could not find complete solutions but only snippets of the sharedInstance method. So I made my own class using..