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  • Different cursor formats in IOFrameBufferShared

    - by Thomi
    Hi, I'm reading the moust cursor pixmap data from the StdFBShmem_t structure, as defined in the IOFrameBufferShared API. Everything works fine, 90% of the time. However, I have noticed that some applications on the mac set a cursor in a different format. According to the documentation for the data structures, the cursor pixmap format should always be in the same format as the frame buffer. My frame buffer is 32BPP. I expect the pixmap data to be in the format 0xAARRGGBB, which is it. However, in some cases, I'm reading data that looks like a mask. Specifically, the pixel will either be 0x00FFFFFF or `0x00000000. This looks to me to be a mask for separate pixel data stored somewhere else. As far as I can tell, the only application that uses this cursor pixel format is Qt Creator, but I need to work with all applications, so I'd like to sort this out. The code I'm using to read the cursor pixmap data is: NSAutoreleasePool *autoReleasePool = [[NSAutoreleasePool alloc] init]; NSPoint mouseLocation = [NSEvent mouseLocation]; NSArray *allScreens = [NSScreen screens]; NSEnumerator *screensEnum = [allScreens objectEnumerator]; NSScreen *screen; NSDictionary *screenDesc = nil; while ((screen = [screensEnum nextObject])) { NSRect screenFrame = [screen frame]; screenDesc = [screen deviceDescription]; if (NSMouseInRect(mouseLocation, screenFrame, NO)) break; } if (screen) { kern_return_t err; CGDirectDisplayID displayID = (CGDirectDisplayID) [[screenDesc objectForKey:@"NSScreenNumber"] pointerValue]; task_port_t taskPort = mach_task_self(); io_service_t displayServicePort = CGDisplayIOServicePort(displayID); io_connect_t displayConnection =0; err = IOFramebufferOpen(displayServicePort, taskPort, kIOFBSharedConnectType, &displayConnection); if (KERN_SUCCESS == err) { union { vm_address_t vm_ptr; StdFBShmem_t *fbshmem; } cursorInfo; vm_size_t size; err = IOConnectMapMemory(displayConnection, kIOFBCursorMemory, taskPort, &cursorInfo.vm_ptr, &size, kIOMapAnywhere | kIOMapDefaultCache | kIOMapReadOnly); if (KERN_SUCCESS == err) { // for some reason, cursor data is not always in the same format as the frame buffer. For this reason, we need // some way to detect which structure we should be reading. QByteArray pixData((const char*)cursorInfo.fbshmem->cursor.rgb24.image[currentFrame], m_mouseInfo.currentSize.width() * m_mouseInfo.currentSize.height() * 4); IOConnectUnmapMemory(displayConnection, kIOFBCursorMemory, taskPort, cursorInfo.vm_ptr); } // IOConnectMapMemory else qDebug() << "IOConnectMapMemory Failed:" << err; IOServiceClose(displayConnection); } // IOServiceOpen else qDebug() << "IOFramebufferOpen Failed:" << err; }// if screen [autoReleasePool release]; My question is: How can I detect if the cursor is a different format from the framebuffer? Where can I read the actual pixel data? the bm18Cursor structure contains a mask section, but it's not in the right place for me to be reading it using the code above. Cheers,

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  • How to allow click-through and a cursor in a background app while not taking the active appearance a

    - by Peter Hosey
    Here are my goals: My application displays an overlay window above all applications' window. The user can draw in the overlay window. The mouse cursor changes to a specific cursor while in the overlay window. The application that has the active appearance before summoning the overlay window still has it while the overlay window is up and usable. The user does not need to click on the overlay window to activate it before they can draw. Drawing in the window does not steal the active appearance away from the application that has it. With LSUIElement, I get #1, #2, #3, and #5. With LSBackgroundOnly, I get #1, #2, #4, and #6. How can I satisify all of these goals without installing an event tap and processing the mouse events myself? Things I've tried: [NSApp preventWindowOrdering] in mouseDown: [NSApp activateIgnoringOtherApps:YES] in applicationWillFinishLaunching: [myWindow orderFront:nil] in applicationWillFinishLaunching: [myWindow makeKeyAndOrderFront:nil] in applicationWillFinishLaunching: [myWindow orderFrontRegardless] in applicationWillFinishLaunching: [myWindow makeMainWindow] in applicationWillFinishLaunching: (this caused failure of point 4 even with LSBackgroundOnly) SetThemeCursor in applicationWillFinishLaunching: (With LSUIElement) Implementing canBecomeMainWindow in my NSPanel subclass to return NO Except where otherwise noted, none of these made any difference. So, with LSUIElement, goals #4 and #6 remain; with LSBackgroundOnly, goals #3 and #5 remain. Any suggestions?

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  • Graphical glitches when adding cells and scrolling with UITableView

    - by Daniel I-S
    I am using a UITableView to display the results of a series of calculations. When the user hits 'calculate', I wish to add the latest result to the screen. This is done by adding a new cell to a 'results' section. The UITableViewCell object is added to an array, and then I use the following code to add this new row to what is displayed on the screen: [thisView beginUpdates]; [thisView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation: UITableViewRowAnimationFade]; [thisView endUpdates]; This results in the new cell being displayed. However, I then want to immediately scroll the screen down so that the new cell is the lowermost cell on-screen. I use the following code: [thisView scrollToRowAtIndexPath:newIndexPath atScrollPosition:UITableViewScrollPositionBottom animated:YES]; This almost works great. However, the first time a cell is added and scrolled to, it appears onscreen only briefly before vanishing. The view scrolls down to the correct place, but the cell is not there. Scrolling the view by hand until this invisible new cell's position is offscreen, then back again, causes the cell to appear - after which it behaves normally. This only happens the first time a cell is added; subsequent cells don't have this problem. It also happens regardless of the combination of scrollToRowAtIndexPath and insertRowsAtIndexPath animation settings. There is also a problem where, if new cells are added repeatedly and quickly, the new cells stop 'connecting up'. The lowermost cell in a group is supposed to have rounded corners, and when a new cell is added these turn into square corners so that there is a clean join with the next cell in the group. In this case, however, a cell often does not lose its rounded edges despite not being the last cell anymore. This also gets corrected once the affected area moves offscreen and back. This method of adding and scrolling would be perfect for my application if it weren't for these weird glitches. Any ideas as to what I may be doing wrong?

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  • Accepting drag operations in an NSCollectionView subclass

    - by andyvn22
    I've subclassed NSCollectionView and I'm trying to receive dragged files from the Finder. I'm receiving draggingEntered: and returning an appropriate value, but I'm never receiving prepareForDragOperation: (nor any of the methods after that in the process). Is there something obvious I'm missing here? Code: - (void)awakeFromNib { [self registerForDraggedTypes:[NSArray arrayWithObjects:NSFilenamesPboardType, nil]]; } - (NSDragOperation)draggingEntered:(id <NSDraggingInfo>)sender { NSLog(@"entered"); //Happens NSPasteboard *pboard; NSDragOperation sourceDragMask; sourceDragMask = [sender draggingSourceOperationMask]; pboard = [sender draggingPasteboard]; if ([[pboard types] containsObject:NSFilenamesPboardType]) { NSLog(@"copy"); //Happens return NSDragOperationCopy; } return NSDragOperationNone; } - (BOOL)prepareForDragOperation:(id <NSDraggingInfo>)sender { NSLog(@"prepare"); //Never happens return YES; }

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  • Convert NSData into Hex NSString

    - by Dawson
    With reference to the following question: Convert NSData into HEX NSSString I have solved the problem using the solution provided by Erik Aigner which is: NSData *data = ...; NSUInteger capacity = [data length] * 2; NSMutableString *stringBuffer = [NSMutableString stringWithCapacity:capacity]; const unsigned char *dataBuffer = [data bytes]; NSInteger i; for (i=0; i<[data length]; ++i) { [stringBuffer appendFormat:@"%02X", (NSUInteger)dataBuffer[i]]; } However, there is one small problem in that if there are extra zeros at the back, the string value would be different. For eg. if the hexa data is of a string @"3700000000000000", when converted using a scanner to integer: unsigned result = 0; NSScanner *scanner = [NSScanner scannerWithString:stringBuffer]; [scanner scanHexInt:&result]; NSLog(@"INTEGER: %u",result); The result would be 4294967295, which is incorrect. Shouldn't it be 55 as only the hexa 37 is taken? So how do I get rid of the zeros? EDIT: (In response to CRD) Hi, thanks for clarifying my doubts. So what you're doing is to actually read the 64-bit integer directly from a byte pointer right? However I have another question. How do you actually cast NSData to a byte pointer? To make it easier for you to understand, I'll explain what I did originally. Firstly, what I did was to display the data of the file which I have (data is in hexadecimal) NSData *file = [NSData dataWithContentsOfFile:@"file path here"]; NSLog(@"Patch File: %@",file); Output: Next, what I did was to read and offset the first 8 bytes of the file and convert them into a string. // 0-8 bytes [file seekToFileOffset:0]; NSData *b = [file readDataOfLength:8]; NSUInteger capacity = [b length] * 2; NSMutableString *stringBuffer = [NSMutableString stringWithCapacity:capacity]; const unsigned char *dataBuffer = [b bytes]; NSInteger i; for (i=0; i<[b length]; ++i) { [stringBuffer appendFormat:@"%02X", (NSUInteger)dataBuffer[i]]; } NSLog(@"0-8 bytes HEXADECIMAL: %@",stringBuffer); As you can see, 0x3700000000000000 is the next 8 bytes. The only changes I would have to make to access the next 8 bytes would be to change the value of SeekFileToOffset to 8, so as to access the next 8 bytes of data. All in all, the solution you gave me is useful, however it would not be practical to enter the hexadecimal values manually. If formatting the bytes as a string and then parsing them is not the way to do it, then how do I access the first 8 bytes of the data directly and cast them into a byte pointer?

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  • Create swipe controlled simple flipbook style animation in ObjC

    - by eco_bach
    Hi I am a beginner in Obj C development, though quite experienced (over 10 years) with other ECMAscript based languages and OOP development. I want to build a simple flipbook style animation, controlled through swiping motion. I'm sure extremely simple for any advanced ObjC coders. Can anyone with extensive ObjC-CocoaTouch experience give me some higher level recommendations? ie, 1 -general application design, should I start with a simple view based application, or navigation based or? 2 -should I use 3rd party animation frameworks such as Cocos2D, or stick with built in classes and methods? 3 -if using built in methods, classes, what is the recommended way of achieving a animation, that will be controlled via swipe and touch gestures? 4 -I want to eventually have multiple 'flipbooks' that I can 'instantly' swap with one another, ie to give the net effect of an object changing color, etc, but not sure how to approach this from a memory management point of view, related to #1 above Except for point 3 above, I'm not expecting any actual code examples. Just general guidelines to follow and perhaps, what are some next steps I should take in my goal as an ObjC code samurai.

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  • UIButton only responds in a small area

    - by Tom Irving
    I'm trying to add a UIButton to a UIView, but am having some trouble with getting it to respond to touches. I have a method which returns UIButtons after I provide it with a tag: - (UIButton*)niceSizeButtonWithTag:(int)tag { UIButton * aButton = [UIButton buttonWithType:UIButtonTypeCustom]; [aButton setTag:tag]; [aButton addTarget:self action:@selector(buttonWasTapped:) forControlEvents:UIControlEventTouchUpInside]; CGRect newFrame = aButton.frame; newFrame.size.width = 44; newFrame.size.height = 44; [aButton setFrame:newFrame]; return aButton; } As you can see I'm creating a new button and increasing the size. I use this in the following way: UIButton * anotherButton = [self niceSizeButtonWithTag:1]; [anotherButton setImage:[UIImage imageNamed:@"image" withExtension:@"png"] forState:UIControlStateNormal]; [anotherButton setCenter:CGPointMake(middleOfView)]; [aView addSubview:anotherButton]; I create a lot of buttons like this, hence the reason for the method. The buttons are always created and added to the subview perfectly. I can see the image and they're in the correct position. The problem is that they only respond to touches in a tiny strip. In this attached image, The yellow shows the whole frame of the button, The red shows the area that will respond to touches. The grey shows a section of the view the button is added to. If anyone could shed some light on why this is happening, it would be really useful.

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  • NSTimer as a timeout mechanism

    - by alexantd
    I'm pretty sure this is really simple, and I'm just missing something obvious. I have an app that needs to download data from a web service for display in a UITableView, and I want to display a UIAlertView if the operation takes more than X seconds to complete. So this is what I've got (simplified for brevity): MyViewController.h @interface MyViewController : UIViewController <UITableViewDelegate, UITableViewDataSource> { NSTimer *timer; } @property (nonatomic, retain) NSTimer *timer; MyViewController.m @implementation MyViewController @synthesize timer; - (void)viewDidLoad { timer = [NSTimer scheduledTimerWithTimeInterval:20 target:self selector:@selector(initializationTimedOut:) userInfo:nil repeats:NO]; [self doSomethingThatTakesALongTime]; [timer invalidate]; } - (void)doSomethingThatTakesALongTime { sleep(30); // for testing only // web service calls etc. go here } - (void)initializationTimedOut:(NSTimer *)theTimer { // show the alert view } My problem is that I'm expecting the [self doSomethingThatTakesALongTime] call to block while the timer keeps counting, and I'm thinking that if it finishes before the timer is done counting down, it will return control of the thread to viewDidLoad where [timer invalidate] will proceed to cancel the timer. Obviously my understanding of how timers/threads work is flawed here because the way the code is written, the timer never goes off. However, if I remove the [timer invalidate], it does.

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  • How do I flag a folder as being a package?

    - by Pierre Bernard
    I used to think that folders needed to have an extension so that they are recognized as packages by the Finder. That extension would be declared in the owning application's Info.plist. Obviously there is another, more elegant way, but I can't figure out how it is done. E.g. the iPhoto Library is being treated as a package by the Finder. Yet it has no extension. mdls reveals that it indeed has "com.apple.package" in the content type tree. The actual content type is dynamically assigned. How did iPhoto go about to create such a directory?

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  • Read Text File in Document Folder - Iphone SDK

    - by Kevin
    Hello everyone I have this code below: NSString *fileName = [[NSUserDefaults standardUserDefaults] objectForKey:@"recentDownload"]; NSString *fullPath = [NSBundle pathForResource:fileName ofType:@"txt" inDirectory:[NSHomeDirectory() stringByAppendingString:@"/Documents/"]]; NSError *error = nil; [textViewerDownload setText:[NSString stringWithContentsOfFile:fullPath encoding: NSUTF8StringEncoding error:&error]]; textviewerdownload is the textview displaying the text from the file. The actual file name is stored in an NSUserDefault called recentDownload. When I build this, I click the button which this is under, and my application crashes. Is there anything wrong with the syntax or just simple error?

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  • Is there a high-level gestures library for iPhone development?

    - by n8gray
    The iPhone platform has a number of common gesture idioms. For example, there are taps, pinches, and swipes, each with varying number of fingers. But when you're developing an app, it's up to you to implement these things based on low-level information about the number and locations of touches. It seems like this is a prime candidate for a library. You would register a delegate, set some parameters like multi-tap interval and swipe threshold, and get calls like swipeStarted/Ended, pinchStarted/Ended, multiTap, etc. Does such a library exist?

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  • Core Data: migrating entities with self-referential properties

    - by Dan
    My Core Data model contains an entity, Shape, that has two self-referential relationships, which means four properties. One pair is a one-to-many relationship (Shape.containedBy <- Shape.contains) and the another is a many-to-many relationship (Shape.nextShapes <<- Shape.previousShapes). It all works perfectly in the application, so I don't think self-referencing relationships is a problem in general. However, when it comes to migrating the model to a new version, then Xcode fails to compile the automatically generated mapping model, with this error message: 2009-10-30 17:10:09.387 mapc[18619:607] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Unable to parse the format string "FUNCTION($manager ,'destinationInstancesForSourceRelationshipNamed:sourceInstances:' , 'contains' , $source.contains) == 1"' *** Call stack at first throw: ( 0 CoreFoundation 0x00007fff80d735a4 __exceptionPreprocess + 180 1 libobjc.A.dylib 0x00007fff83f0a313 objc_exception_throw + 45 2 Foundation 0x00007fff819bc8d4 _qfqp2_performParsing + 8412 3 Foundation 0x00007fff819ba79d +[NSPredicate predicateWithFormat:arguments:] + 59 4 Foundation 0x00007fff81a482ef +[NSExpression expressionWithFormat:arguments:] + 68 5 Foundation 0x00007fff81a48843 +[NSExpression expressionWithFormat:] + 155 6 XDBase 0x0000000100038e94 -[XDDevRelationshipMapping valueExpressionAsString] + 260 7 XDBase 0x000000010003ae5c -[XDMappingCompilerSupport generateCompileResultForMappingModel:] + 2828 8 XDBase 0x000000010003b135 -[XDMappingCompilerSupport compileSourcePath:options:] + 309 9 mapc 0x0000000100001a1c 0x0 + 4294973980 10 mapc 0x0000000100001794 0x0 + 4294973332 ) terminate called after throwing an instance of 'NSException' Command /Developer/usr/bin/mapc failed with exit code 6 The 'contains' is the name of one of the self-referential properties. Anyway, the really big problem is that I can't even look at this Mapping Property as Xcode crashes as soon as I select the entity mapping when viewing the mapping model. So I'm a bit lost really where to go from here. I really can't remove the self-referential properties, so I'm thinking I've got manually create a mapping model that compiles? Any ideas? Cheers

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  • How to manually manage Core Data relationships when deleting

    - by Simon
    I have a Core Data entity, which contains a relationship to another entity. Under certain circumstances, I need to delete the managed objects in the relationship, and at other times no action needs to be taken. I have the Delete Rule on the entity is No Action because of this manual management. The problem I have is, where is the best place to enforce these rules? I cannot see any suitable messages to override on NSManagedObject (something that might notify the object it has been deleted and should clear up its relationships). I would rather not do it higher up in the application logic, because the entity objects can get deleted from array controllers and at different points in the applications, making it necessary to stuff relationship update code at all those levels.

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  • Filter entire NSDictionaries out of NSArray based on multiple keys

    - by user270475
    Hi, I have an NSArray of NSDictionary objects which I would like to be able to return a new array of NSDictionaries from, where every NSDictionary has "Area == North" (for example). The closest example I have found so far is http://stackoverflow.com/questions/958622/using-nspredicate-to-filter-an-nsarray-based-on-nsdictionary-keys but this just returns the unique values for a given key, not the dictionary that has that key. Is there any way to perform a similar operation, and to return the entire dictionary?

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  • Mixing garbage collected framework with normal code

    - by shw
    I know my way around Objective-C and I have experience with garbage collection from .NET, although I never used it in objective-c. I write my code without using it. Now I'm thinkig about using one of the frameworks (Blocks) which is available as GC-only. My question is - can I still use the framework without any changes to my current non-GC code and without using GC myself?

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  • Can I avoid explicitly casting objects with a common subclass?

    - by prendio2
    I have an iPodLibraryGroup object and Artist and Album both inherit from it. When it comes to my view controllers though I find that I'm duplicate lots of code, for example I have an ArtistListViewController and and AlbumListViewController even though they're both doing basically the same thing. The reason I've ended up duplicating the code is because these view controllers each refer to either an Artist object or al Album object and I'm not sure how to set it up so that one view controller could handle both — these view controllers are mainly accessing methods that that the objects have in common from iPodLibraryGroup. As an example, to hopefully make this clearer consider this code in AlbumListViewController: - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { Album *album = nil; album = [self albumForRowAtIndexPath:indexPath inTableView:tableView]; … if (!album.thumbnail) { [self startThumbnailDownload:album forIndexPath:indexPath inTableView:tableView]; cell.imageView.image = [UIImage imageNamed:@"Placeholder.png"]; } else { cell.imageView.image = album.thumbnail; } return cell; } This is essentially completely repeated (along with a hell of a lot more repeated code) in ArtistListViewController just so that I can typecast the local variable as an Artist instead of an Album. Is there a way to not explicitly need to set Artist or Album here so that the same code could work for any object that is a child of iPodLibraryGroup?

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  • Best way to show a loading screen in an iPhone app?

    - by pkulak
    I'm building what is essentially a web app. Every piece of data has to be fetched from a web API. So, every UITableView that I show takes some amount of time to fill with data and I'm struggling to find a good way to show the user a loading screen. Right now I'm popping up an action sheet, but that just seems a bit wrong. Ideally, I'd popup up a blank view over the tableview with "Loading..." on it, then fade it away when the data comes in, but I can't think of a way to do that in 8 places in my app without massive code duplication.

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  • What's a better way to display a handle for resizing a view on iPhone / iPad?

    - by Christian
    I want to display a handle at the corners of a UIView that can be used to resize the view. How can I display the handles floating on the top of everything else and still have a connection to and be in sync with a view? The solution I implemented before looks like this: I put the view into another view that shows the handles on top of the corners. The problem with this approach is that the handles add extra space to the original view's size. Since Apple recommends at least 40 x 40 px for the size of a button, it is not very little space and also goes beyond the visible bounds of the original view. Another problem is that the original view has to be encapsulated in this 'helper view' object and thus becomes a part of something although it really is the main component.

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  • Using Reachability for Internet *or* local WiFi?

    - by randallmeadows
    I've searched SO for the answer to this question, and it's not really addressed, at least not to a point where I can make it work. I was originally only checking for Internet reachability, using: self.wwanReach = [Reachability reachabilityWithHostName:@"www.apple.com"]; [wwanReach startNotifer]; I now need to support a local WiFi connection (in the absence of reaching the Internet in general), and when I found +reachabilityForLocalWiFi, I also noticed there was +reachabilityForInternetConnection. I figured I could use these, instead of hard-coding "www.apple.com" in there, but alas, when I use self.wwanReach = [Reachability reachabilityForInternetConnection]; [wwanReach startNotifer]; self.wifiReach = [Reachability reachabilityForLocalWiFi]; [wifiReach startNotifer]; the reachability callback that I've set up "never" gets called, for values of "never" up to 10, 12, 15 minutes or so (which was as long as my patience lasted. (User's patience will be much less, I'm sure.) Switching back to +reachabilityWithHostName: works within seconds. I also tried each "pair" individually, in case there was an issue with two notifiers in progress simultaneously, but that made no difference. So: what is the appropriate way to determine reachability to either the Internet/WWAN or a local Wifi network (either one, or both)? [This particular use case is an iPhone or iPad connecting to a Mac mini computer-to-computer network; I'm sure other situations apply.]

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  • Does UIActivityIndicator require manual threading on iPhone

    - by Akusete
    I am running creating an iPhone application which performs a costly operation and I wanted to create an activityIndicator to let the user know the application has not frozen. The operation is performed entirely in one event call... so there is no chance for the UI framework to receive control to actually display and animate this indicator. The sample apps which use the UIActivityIndicator (or any other similar animation) start and stop the animation in different events, triggered separately at different stages of the program. Do I need to manually create a separate thread to run my operation in, or is there already default support for this kind of behavior?

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  • Setting up a "to-many" relationship value dependency for a transient Core Data attribute

    - by Greg Combs
    I've got a relatively complicated Core Data relationship structure and I'm trying to figure out how to set up value dependencies (or observations) across various to-many relationships. Let me start out with some basic info. I've got a classroom with students, assignments, and grades (students X assignments). For simplicity's sake, we don't really have to focus much on the assignments yet. StudentObj <--->> ScoreObj <<---> AssignmentObj Each ScoreObj has a to-one relation with the StudentObj and the AssignmentObj. ScoreObj has real attributes for the numerical grade, the turnInDate, and notes. AssignmentObj.scores is the set of Score objects for that assignment (N = all students). AssignmentObj has real attributes for name, dueDate, curveFunction, gradeWeight, and maxPoints. StudentObj.scores is the set of Score objects for that student (N = all assignments). StudentObj also has real attributes like name, studentID, email, etc. StudentObj has a transient (calculated, not stored) attribute called gradeTotal. This last item, gradeTotal, is the real pickle. it calculates the student's overall semester grade using the scores (ScoreObj) from all their assignments, their associated assignment gradeWeights, curves, and maxPoints, and various other things. This gradeTotal value is displayed in a table column, along with all the students and their individual assignment grades. Determining the value of gradeTotal is a relatively expensive operation, particularly with a large class, therefore I want to run it only when necessary. For simplicity's sake, I'm not storing that gradeTotal value in the core data model. I don't mind caching it somewhere, but I'm having a bitch of a time determining where and how to best update that cache. I need to run that calculation for each student whenever any value changes that affects their gradeTotal. If this were a simple to-one relationship, I know I could use something like keyPathsForValuesAffectingGradeTotal ... but it's more like a many-to-one-to-many relationship. Does anyone know of an elegant (and KVC correct) solution? I guess I could tear through all those score and assignment objects and tell them to register their students as observers. But this seems like a blunt force approach.

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  • Problem with reading data from plist iphone sdk

    - by neha
    Hi all, I'm creating a myDb.plist file in my resources folder and trying to read it, but it's not getting read. I'm using the following code. NSString* plistPath = [[NSBundle mainBundle] pathForResource:@"myDb" ofType:@"plist"]; contentArray = [NSArray arrayWithContentsOfFile:plistPath]; contentArray is showing null. Can anybody please help me? Thanx in advance.

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  • NSTableView selection & highlights

    - by Christian
    I have a NSTableView as a very central part of my Application and want it to integrate more with the rest of it. It has only one column (it's a list) and I draw all Cells (normal NSTextFieldCells) myself. The first problem is the highlighting. I draw the highlight myself and want to get rid of the blue background. I now fill the whole cell with the original background color to hide the blue background, but this looks bad when dragging the cell around. I tried overriding highlight:withFrame:inView: and highlightColorWithFrame:inView: of NSCell but nothing happened. How can I disable automatic highlighting? I also want all rows/cells to be deselected when I click somewhere outside my NSTableView. Since the background / highlight of the selected cell turns gray there must be an event for this, but I can't find it. I let my cells expand on a double click and may need to undo this. So getting rid of the gray highlight is not enough. EDIT: I add a subview to the NSTableView when a cell gets double clicked and then resignFirstResponder of the NSTableView gets called. I tried this: - (BOOL)resignFirstResponder { if (![[self subviews] containsObject:[[self window] firstResponder]]) { [self deselectAll:self]; ... } return YES; } Besides that it's not working I would need to implement this method for all objects in the view hierarchy. Is there an other solution to find out when the first responder leaves a certain view hierarchy?

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