objective-c

NSString value not same across method calls?

I have an Objective-C method that formats a double to a currency NSString: - (NSString*) formatCurrencyValue:(double)value { NSNumberFormatter *numberFormatter = [[[NSNumberFormatter alloc] init] autorelease]; [numberFormatter setFormatterBehavior:NSNumberFormatterBehaviorDefault]; [numberFormatter setCurrencySymbol:@"$"]; ...

How do I call a variable from another class?

I have a class called 'Constants' that I am storing a String variable in. This class contains a few global variables used in my app. I want to be able to reference this class and call the variable (called profileId) in other Views of my app. I looked around and found a few examples, but am not sure how to do this. Currently my setup is...

iPhone not returning to application after calling eMail send

I am sending an email from within my iPhone application. The eMail page pops up ok, I click on the Send button, the iPhone plays a whoosh sound, and the eMail actually arrives at the recipient. Unfortunately, the mail dialog still sits there unresponsive, and the only option - to click the home button - kills the app. Is there somethi...

UIImages on UITableView?

what is the best method to display about 300 png images into a UITableView.. i dont wanna display them at the same time... i have 3 tableViewControllers that will each display about 100 imgaes.. (its for a catalog so the images are important to display) i used [uiimage imageNamed:] but that method caches the images and they dont get ...

What's the difference between single and double quotes in Objective-C?

I'm working through a book exercise to generate some random serial number, and here's my function: NSString *randomSerialNumber = [NSString stringWithFormat:@"%c%c%c%c%c", '0' + random() % 10, 'A' + random() % 26, '0' + random() %...

Accessing the stringValue from NSTextFields on different NIBs

I'm having an extremely difficult time trying to access information from an object (e.g. an NSTextField) that is located on a NIB other than my "MainMenu.nib". My current setup: I have a MainMenu.xib that contains only a toolbar at the top and an NSView. I have four other .xib files containing custom NSViews and each of their File Owner...

Difference between objective-c and java

i'm experienced with Java and want to learn objective-c to write apps for the iPhone. What are some fundamental differences? (other than syntax) ...

OpenGL behaving strangely

OpenGL is acting very strangely for some reason. In my subclass of NSOpenGLView, I have the following code in the -prepareOpenGL method: - (void)prepareOpenGL { GLfloat lightAmbient[] = { 0.5f, 0.5f, 0.5f, 1.0f }; GLfloat lightDiffuse[] = { 1.0f, 1.0f, 1.0f, 1.0f }; GLfloat lightPosition[] = { 0.0f, 0.0f, 2.0f }; quality = 0; zCoo...

How can I access data that's stored in my App Delegate from my various view controllers?

This question is similar to this other post, but I'm new to iPhone development and I'm getting used to the good practices for organizing my data throughout my app. I understand the ApplicationDelegate object to be the best place to manage data that is global to my app, correct? If so, how can I access data that's stored in my App Deleg...

How do I refer to a view controller in a subclass?

Hey all, I'm currently teaching myself Objective C and I'm kind of stuck. I'm building a backgammon game and I have a subclass, "Piece", which is being initialized, repeatedly, in BackGammonViewController. In BackGammonViewController, if I do this: UIImage *myImage = [ UIImage imageNamed: @"white-piece.png" ]; UIImageView *myImageVie...

How important is managing memory in Objective-C?

Background: I'm (jumping on the bandwagon and) starting learning about iPhone/iPad development and Objective-C. I have a great background in web development and most of my programming is done in javascript (no libraries), Ruby, and PHP. Question: I'm learning about allocating and releasing memory in Objective-C, and I see it as quite a ...

Beat Detection on iPhone with wav files and openal

Using this website i have tried to make a beat detection engine. http://www.gamedev.net/reference/articles/article1952.asp { ALfloat energy = 0; ALfloat aEnergy = 0; ALint beats = 0; bool init = false; ALfloat Ei[42]; ALfloat V = 0; ALfloat C = 0; ALshort *hold; hold = new ALshort[[myDat length]/2]; [myDat getBytes:hold length:[myD...

Skype Mac API - Use AppleScript or 5 year old API?

I have a x86_64 app that I would like to have optionally read Skype status messages. However, the 5 year old skype mac framework is 32-bit, and if there is a way to have that compile within a 64-bit app, I haven't found it. My question is, basically, how should I go about doing this? I really only need to get and set the USERSTATUS AWA...

OO model for nsxmlparser when delegate is not self

Hi, I am struggling with the correct design for the delegates of nsxmlparser. In order to build my table of Foos, I need to make two types of webservice calls; one for the whole table and one for each row. It's essentially a master-query then detail-query, except the master-query-result-xml doesn't return enough information so i then n...

how to tell which object called a delegate method (objective c)

Let's say you have two objects (for example, a UITextviews, but it could be any type) in your class. When the text view changes, you have a delegate method that catches the change.. but how can you tell programatically WHICH object was changed and called the delegate ?? (Possible thought) Basically how to you get the variable name of a...

I know I can't say myView.frame.origin.x = val - But why ?

I know that I can't use that myView.frame.origin.x = 25.0; that I have to use instead CGRect myFrame = myView.frame; myFrame.origin.x = 25.0; myView.frame = myFrame; And I'm doing it all the time (f.e. in animations), but I don't know why I must do it that way. I would like to fill that gap in my understanding. Can someone explain ...

How does one access subviews and handle groups of them?

If I want to manipulate a view I get it with [self viewWithTag:5];. Is there a better way to do this? Sometimes I need to manipulate a bunch of view (e.g. move them all out of the way. I do this by adding a UIView (e.g. UIView iHoldViews) and then adding the views, buttons, etc to this view. Then I can move the iHoldViews view and all i...

Add shading to clipped UIView

I'm creating an iphone application. I have this UIView whose content is clipped with a path. I want to add shading and/or shadow to it. What's the best way to do this? For shadow, I tried CGContextSetShadow() but it doesn't seem to have an effect (perhaps it's drawing outside the shown region?) . How about shading? I want it to appear al...

Is there any way to get the iPhone Model number ?

I just figure out the device on which i'm working by the code given bellow: struct utsname systemInfo; uname(&systemInfo); NSLog(@"%@", [NSString stringWithCString:systemInfo.version encoding:NSUTF8StringEncoding]); But is there any way to find the model of my iPhone??? Thanks in advance .... ...

Best way of testing if an NSImage / CGImageRef is completely transparent

I have an image with tiles that I am splitting up and creating individual tiles with. However, these images typically contain completely blank areas (tiles in this case) that I wish to exclude. These areas are completely transparent. Now, how do I go about detecting them? Could read the tile pixel by pixel, by way of NSBitmapImageRep...