Search Results

Search found 12588 results on 504 pages for 'memory allocation'.

Page 143/504 | < Previous Page | 139 140 141 142 143 144 145 146 147 148 149 150  | Next Page >

  • Effect of 'myObj = [[[[MyClass alloc] init] autorelease] retain];'?

    - by filipe
    I've just downloaded the Facebook iOS SDK and I noticed that in the sample code that comes with the SDK whenever it creates an instance of the Facebook class it does it like this: _facebook = [[[[Facebook alloc] init] autorelease] retain]; where _facebook is a member variable of the calling object (i.e. not a local variable). Can anyone explain exactly what's the point of autoreleasing and then retaining it?

    Read the article

  • Objective-C: when does an assigned object get deallocated

    - by Stefan Klumpp
    If I have a instance method and within this method I do something like this: NSString *peopleString = [peopleList componentsJoinedByString: @", "]; ... UILabel *likeLabel = [[UILabel alloc] initWithFrame:CGRectMake(16.0+6.0f, 4.0f, 252.0f, 12.0f)]; [likeLabel setText:peopleString]; [likeLabel setFont:[UIFont fontWithName:@"Arial" size:12]]; [likeRow addSubview:likeLabel]; [likeLabel release]; The componentsJoinedByString doesn't contain a new, copy or alloc, thus I don't have to release it. What I'm wondering though is, when my peopleString gets deallocated. Might it happen to early? Meaning, before I can set the text in my label. Should I better use a [[NSString alloc] initWithString:[peopleList componentsJoinedByString: @", "]]; and release it at the end of this method?

    Read the article

  • dealloc properties with assign and readwrite objective-c

    - by okami
    I have this structure: @interface MyList : NSObject { NSString* operation; NSString* link; } @property (readwrite) NSString* operation; @property (readwrite, assign) NSString* link; @end @implementation MyList @synthesize operation,link; @end I know that if I had retain instead of readwrite I should release the operation and link properties. BUT should I release the operation and link with the code above?

    Read the article

  • When to release the UIImage ?

    - by ragnarius
    I use the following code to draw a subimage UIImage* subIm = getSubImage( large, rect ); [subIm drawInRect:self.bounds]; where getSubImage is defined as follows UIImage* getSubImage(UIImage* uim, CGRect rc){ CGImageRef imref = CGImageCreateWithImageInRect(uim.CGImage, rc); UIImage* sub = [UIImage imageWithCGImage:imref]; CGImageRelease(imref); NSLog(@"subimage retainCount=%d", [sub retainCount]); // is 1 return sub; }//getSubImage Is the code correct? Is it safe to "CGImageRelease" imref? Has sub "CGImageRetained" imref? Should I release subIm (I get an error if I do)? Is subIm contained in the autorelease-pool, and , if so, how do I know this? In general, can one check if an object is contained in the autorelease pool (for debugging purpose)?

    Read the article

  • Retain cycle on `self` with blocks

    - by Jonathan Sterling
    I'm afraid this question is pretty basic, but I think it's relevant to a lot of Objective-C programmers who are getting into blocks. What I've heard is that since blocks capture local variables referenced within them as const copies, using self within a block can result in a retain cycle, should that block be copied. So, we are supposed to use __block to force the block to deal directly with self instead of having it copied. __block typeof(self) bself = self; [someObject messageWithBlock:^{ [bself doSomething]; }]; instead of just [someObject messageWithBlock:^{ [self doSomething]; }]; What I'd like to know is the following: if this is true, is there a way that I can avoid the ugliness (aside from using GC)?

    Read the article

  • Exemple where TYPE_ALIGNMENT() fails

    - by JustMaximumPower
    Hi, I have a question relating to alignment in c/c++. In http://stackoverflow.com/questions/364483/determining-the-alignment-of-c-c-structures-in-relation-to-its-members Michael Burr posted this Makro: #define TYPE_ALIGNMENT( t ) offsetof( struct { char x; t test; }, test ) in the comments someone wrote this might fail with non POD typs. Can someone give me an code example where this fails?

    Read the article

  • Practicing buffer overflow attack in Ubuntu

    - by wakandan
    I am trying to learn to use buffer overflow attack in Ubuntu. Unfortunately, I cannot turn off Address Space Layout Randomization (ASLR) feature in this OS, which is turned on by default. I have tried some work around found in some fedora books: echo "0" > /proc/sys/kernel/randomize_va_space but for some reason the protection's still there. Please give me some suggestions. Thanks. [edit]Actually the above command was not successful, it said "Permission Denied", even with sudo. How can I fix that? [adding] I kept on getting segmetation fault error when it shows an address in stack. Is it related to non-executable stack in ubuntu :(?

    Read the article

  • Objective-c garbage collection

    - by Chris
    If garbage collection is not required: - (void) awakeFromNib{ //Create the NSStatusBar and set its length statusItem = [[[NSStatusBar systemStatusBar] statusItemWithLength:NSSquareStatusItemLength] retain]; ... Do I have to release that? And if I do, would that be in a finalize method or dealloc method? If garbage collection is required, then is the retain call above ignored automatically?

    Read the article

  • App crashes every second time a tableview row is selected in navigation controller setup

    - by Thaurin
    Disclaimer first: I'm pretty new to Objective-C and the retain model. I've been developing in a garbage collected .NET environment for the last five years, so I've been spoiled. I'm still learning. I'm having my iPhone app crash with EXC_BAD_ACCESS. It happens in a navigtation controller/tableview setup. When I select a row the first time, no problems. It switches in the child controller without problems. I go back and select the same row again. Program then proceeds to crash. Every other row works fine, but every second time a row is accessed, it's a crash. I've pinpointed the location where this happens. The child controller (which is a class that I reuse for every row of the same type) that's being switched into has an array of NSString's representing the rows that will be displayed. I set it before pushing the child viewcontroller. It's there where this apparently happens. I'm having a hard time debugging this problem, still wrestling with xcode and all. I fear there may be some vital information missing here, but maybe there is something you recognize here.

    Read the article

  • Using CreateFileMapping between to programs - C

    - by Jamie Keeling
    Hello, I have two window form applications written in C, one holds a struct consisting of two integers, another will receive it using the CreateFileMapping. Although not directly related I want to have three events in place so each of the processes can "speak" to each other, one saying that the first program has something to pass to the second, one saying the first one has closed and another saying the second one has closed. What would be the best way about doing this exactly? I've looked at the MSDN entry for the CreateFileMapping operation but I'm still not sure as to how it should be done. I didn't want to start implementing it without having some sort of clear idea as to what I need to do. Thanks for your time.

    Read the article

  • Returning a local object from a function

    - by pocoa
    Is this the right way to return an object from a function? Car getCar(string model, int year) { Car c(model, year); return c; } void displayCar(Car &car) { cout << car.getModel() << ", " << car.getYear() << endl; } displayCar(getCar("Honda", 1999)); I'm getting an error, "taking address of temporary". Should I use this way: Car &getCar(string model, int year) { Car c(model, year); return c; }

    Read the article

  • Can get members, but not count of NSMutableArray

    - by Curyous
    I'm filling an NSMutableArray from a CoreData call. I can get the first object, but when I try to get the count, the app crashes with Program received signal: “EXC_BAD_ACCESS”. How can I get the count? Here's the relevant code - I've put a comment on the line where it crashes. - (void)viewDidLoad { [super viewDidLoad]; managedObjectContext = [[MySingleton sharedInstance] managedObjectContext]; if (managedObjectContext != nil) { charactersRequest = [[NSFetchRequest alloc] init]; charactersEntity = [NSEntityDescription entityForName:@"Character" inManagedObjectContext:managedObjectContext]; [charactersEntity retain]; [charactersRequest setEntity:charactersEntity]; [charactersRequest retain]; NSError *error; characters = [[managedObjectContext executeFetchRequest:charactersRequest error:&error] mutableCopy]; if (characters == nil) { NSLog(@"Did not get results for characters: %@", error.localizedDescription); } else { [characters retain]; NSLog(@"Found some character(s)."); Character* character = (Character *)[characters objectAtIndex:0]; NSLog(@"Name of first one: %@", character.name); NSLog(@"Found %@ character(s).", characters.count); // Crashes on this line with - Program received signal: “EXC_BAD_ACCESS”. } } } And previous declarations from the header file: @interface CrowdViewController : UITableViewController { NSManagedObjectContext *managedObjectContext; NSFetchRequest *charactersRequest; NSEntityDescription *charactersEntity; NSMutableArray *characters; } I'm a bit perplexed and would really appreciate finding out what is going on.

    Read the article

  • Removing DOM event handlers in long-running browser session

    - by Chris Beck
    I have a browser interface with a ul#contacts list on the left and div#contact property panel (email, phone) on the right. Click a contact in the list and my app makes an XHR request to get the contact property HTML fragment and update div#contact.innerHTML. Each contact fragment has an "Edit Contact" link. With JS, I progressively upgrade that link with an event listener that performs an XHR request to replace the static property panel with an in-place edit form. This can happen many times during a single browser session. How should I clean up my "Edit Contact" event listener? Do I need to remove it manually before the form overwrites the property panel? Or is the event listener cleaned up automatically when the contents of div#contact (and the node that I'm listening on) is overwritten? FWIW, I still consider IE6 to be part of my target market.

    Read the article

  • UIVIewController not released when view is dismissed

    - by Nelson Ko
    I have a main view, mainWindow, which presents a couple of buttons. Both buttons create a new UIViewController (mapViewController), but one will start a game and the other will resume it. Both buttons are linked via StoryBoard to the same View. They are segued to modal views as I'm not using the NavigationController. So in a typical game, if a person starts a game, but then goes back to the main menu, he triggers: [self dismissViewControllerAnimated:YES completion:nil ]; to return to the main menu. I would assume the view controller is released at this point. The user resumes the game with the second button by opening another instance of mapViewController. What is happening, tho, is some touch events will trigger methods on the original instance (and write status updates to them - therefore invisible to the current view). When I put a breakpoint in the mapViewController code, I can see the instance will be one or the other (one of which should be released). I have tried putting a delegate to the mainWindow clearing the view: [self.delegate clearMapView]; where in the mainWindow - (void) clearMapView{ gameWindow = nil; } I have also tried self.view=nil; in the mapViewController. The mapViewController code contains MVC code, where the model is static. I wonder if this may prevent ARC from releasing the view. The model.m contains: static CanShieldModel *sharedInstance; + (CanShieldModel *) sharedModel { @synchronized(self) { if (!sharedInstance) sharedInstance = [[CanShieldModel alloc] init]; return sharedInstance; } return sharedInstance; } Another post which may have a lead, but so far not successful, is UIViewController not being released when popped I have in ViewDidLoad: // checks to see if app goes inactive - saves. [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(resignActive) name:UIApplicationWillResignActiveNotification object:nil]; with the corresponding in ViewDidUnload: [[NSNotificationCenter defaultCenter] removeObserver:self name:UIApplicationWillResignActiveNotification object:nil]; Does anyone have any suggestions? EDIT: - (void) prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{ NSString *identifier = segue.identifier; if ([identifier isEqualToString: @"Start Game"]){ gameWindow = (ViewController *)[segue destinationViewController]; gameWindow.newgame=-1; gameWindow.delegate = self; } else if ([identifier isEqualToString: @"Resume Game"]){ gameWindow = (ViewController *)[segue destinationViewController]; gameWindow.newgame=0; gameWindow.delegate = self;

    Read the article

  • EXEC_BAD_ACCESS error comes in my applicatoin in iphone

    - by Jaimin
    when i print dictionary i got this error.. here my dictTf is mutabledictionay.. when i m in home page i selct few fields and click find. so new view comes with the result.. now i go back and again click find without changing anything.. now comes proper.. now at this moment when i go back it shows this in the dictionay and EXEC_BAD_ACCESS eror comes... Printing description of dictTf: The program being debugged was signaled while in a function called from GDB. GDB has restored the context to what it was before the call. To change this behavior use "set unwindonsignal off" Evaluation of the expression containing the function (CFShow) will be abandoned. The program being debugged was signaled while in a function called from GDB. GDB has restored the context to what it was before the call. To change this behavior use "set unwindonsignal off" Evaluation of the expression containing the function (CFShow) will be abandoned. (gdb)

    Read the article

  • Container for database-like searches

    - by Milan Babuškov
    I'm looking for some STL, boost, or similar container to use the same way indexes are used in databases to search for record using a query like this: select * from table1 where field1 starting with 'X'; or select * from table1 where field1 like 'X%'; I thought about using std::map, but I cannot because I need to search for fields that "start with" some text, and not those that are "equal to". I could create a sorted vector or list and use binary search (breaking the set in 2 in each step by reading the element in the middle and seeing if it's more or less than 'X'), but I wonder if there is some ready-made container I could use without reinventing the wheel?

    Read the article

  • Compute jvm heap size to host web application

    - by Enrique
    Hello, I want to host a web application on a private JVM they offer 32, 64, 128, 256 MB plans. My web application uses Spring. And I store some objects for every logged in user session. My question is: How can I profile my web app to see how much heap size it needs so I can choose a plan?, How can I simulate hundreds of users logged in at the same time? I'm developing the application using Netbeans 6.7 Java 1.6 Tomcat 6.0.18 Thank you.

    Read the article

  • XMLHttpRequest leak

    - by Raja
    Hi everyone, Below is my javascript code snippet. Its not running as expected, please help me with this. <script type="text/javascript"> function getCurrentLocation() { console.log("inside location"); navigator.geolocation.getCurrentPosition(function(position) { insert_coord(new google.maps.LatLng(position.coords.latitude,position.coords.longitude)); }); } function insert_coord(loc) { var request = new XMLHttpRequest(); request.open("POST","start.php",true); request.onreadystatechange = function() { callback(request); }; request.setRequestHeader("Content-Type","application/x-www-form-urlencoded"); request.send("lat=" + encodeURIComponent(loc.lat()) + "&lng=" + encodeURIComponent(loc.lng())); return request; } function callback(req) { console.log("inside callback"); if(req.readyState == 4) if(req.status == 200) { document.getElementById("scratch").innerHTML = "callback success"; //window.setTimeout("getCurrentLocation()",5000); setTimeout(getCurrentLocation,5000); } } getCurrentLocation(); //called on body load </script> What i'm trying to achieve is to send my current location to the php page every 5 seconds or so. i can see few of the coordinates in my database but after sometime it gets weird. Firebug show very weird logs like simultaneous POST's at irregular intervals. Here's the firebug screenshot: IS there a leak in the program. please help. EDIT: The expected outcome in the firebug console should be like this :- inside location POST .... inside callback /* 5 secs later */ inside location POST ... inside callback /* keep repeating */

    Read the article

  • NSURLConnection shown as leaking in instruments

    - by Gyozo Kudor
    Hello another stupid question regarding leaks and also NSURLConnection. How do i release it? Is it enough if i release in the following 2 methods? (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error (void)connectionDidFinishLoading:(NSURLConnection *)connection Because in instruments it shows me the line where I alloc my connection as the source of leaking. OK I don't get it. After the following code my urlConnection has a retain count of 2. WTF? NSURLConnection *urlConnection = [[NSURLConnection alloc] initWithRequest: urlRequest delegate: self]; This is the line that instruments points me to. I find this very weird.

    Read the article

  • How do i free objects in C#

    - by assassin
    Hi, Can anyone please tell me how I can free objects in C#? For example, I have an object: Object obj1 = new Object(); //Some code using obj1 //Here I would like to free obj1, after it is no longer required and also more importantly its scope is the full run time of the program. Thanks for all your help

    Read the article

  • C++ -malign-double compiler flag

    - by Martin
    I need some help on compiler flags in c++. I'm using a library that is a port to linux from windows, that has to be compiled with the -malign-double flag, "for Win32 compatibility". It's my understanding that this mean I absolutely have to compile my own code with this flag as well? How about other .so shared libraries, do they have be recompiled with this flag as well? If so, is there any way around this? I'm a linux newbie (and c++), so even though I tried to recompile all the libraries I'm using for my project, it was just too complicated to recursively find the source for all the libraries and the libraries they're dependent on, and recompile everything.

    Read the article

  • How to relink existing shared library with extra object file

    - by awy
    I have existing Linux shared object file (shared library) which has been stripped. I want to produce a new version of the library with some additional functions included. I had hoped that something like the following would work, but does not: ld -o newlib.so newfuncs.o --whole-archive existinglib.so I do not have the source to the existing library. I could get it but getting a full build environment with the necessary dependencies in place would be a lot of effort for what seems like a simple problem.

    Read the article

< Previous Page | 139 140 141 142 143 144 145 146 147 148 149 150  | Next Page >