With `UIKit` Apple added support for CGPoint to `NSValue`, so you can do:

    NSArray *points = [NSArray arrayWithObjects:
                         [NSValue valueWithCGPoint:CGPointMake(5.5, 6.6)],
                         [NSValue valueWithCGPoint:CGPointMake(7.7, 8.8)],
                         nil];

List as many [NSValue] instances as you have CGPoint, and end the list in nil. All objects in this structure are auto-released.

On the flip side, when you&#39;re pulling the values out of the array:

    NSValue *val = [points objectAtIndex:0];
    CGPoint p = [val CGPointValue];



I use this:

Create array:

    NSArray *myArray = @[[NSValue valueWithCGPoint:CGPointMake(30.0, 150.0)],[NSValue valueWithCGPoint:CGPointMake(41.67, 145.19)]];



Get 1st CGPoint object:
    
    CGPoint myPoint = [myArray[0] CGPointValue];

You can also write this in a minimal form of:

    CGPoint myArray[] = { CGPointMake(5.5, 6.6), CGPointMake(7.7, 8.8) };
    
    CGPoint p2 = myArray[1];

Have you taken a look at `CFMutableArray`? That might work better for you.

Why is `UnhandledExceptionEventArgs.ExceptionObject` an object and not an `Exception`?

I am attaching to `AppDomain.UnhandledException`.

I would like to cast `UnhandledExceptionEventArgs.ExceptionObject` to an `Exception` and interogate it.

And with this in mind will it ever be null?

The [MSDN documentation][1] is not exatly useful.

&gt; Gets the unhandled exception object.




  [1]: http://msdn.microsoft.com/en-us/library/system.unhandledexceptioneventargs.exceptionobject.aspx

Why is UnhandledExceptionEventArgs.ExceptionObject an object and not an Exception?

We&#39;re currently using subversion on a relatively large codebase. Each release gets its own branch, and fixes are performed against the trunk and migrated into release branches using `svnmerge.py`

I believe the time has come to move on to better source control, and I&#39;ve been toying with Mercurial for a while.

There seems to be two schools of though on managing such a release structure using Mercurial.  Either each release gets its own repo, and fixes are made against the release branch and pushed to the main branch (and any other newer release branches.)  OR using named branches within a single repository (or multiple matching copies.)

In either case it seems like I might be using something like transplant to cherrypick changes for inclusion in the release branches.

I ask of you; what are the relative merits of each approach?

Named Branches vs Multiple Repositories

I have about 50 CGPoint objects that describe something like a &quot;path&quot;, and I want to add them to an NSArray. It&#39;s going to be a method that will just return the corresponding CGPoint for an given index. I don&#39;t want to create 50 variables like p1 = ...; p2 = ..., and so on. Is there an easy way that would let me to define those points &quot;instantly&quot; when initializing the NSArray with objects?


How can I add CGPoint objects to an NSArray the easy way?

<p>I have about 50 CGPoint objects that describe something like a "path", and I want to add them to an NSArray. It's going to be a method that will just return the corresponding CGPoint for an given index. I don't want to create 50 variables like p1 = ...; p2 = ..., and so on. Is there an easy way that would let me to define those points "instantly" when initializing the NSArray with objects?</p>


How do I convert an `NSString` value to `NSData`?

How do I convert an NSString value to NSData?

I&#39;m surfing through the wonderful blog maintained by Scott Stevenson, and I&#39;m trying to understand a fundamental Objective-C concept of assigning delegates the &#39;assign&#39; property vs &#39;retain&#39;. Note, the both are the same in a garbage collected environment. I&#39;m mostly concerned with a non-GC based environment (eg: iPhone).

Directly from Scott&#39;s blog:

&quot;The assign keyword will generate a setter which assigns the value to the instance variable directly, rather than copying or retaining it. This is best for primitive types like NSInteger and CGFloat, or objects you don&#39;t directly own, such as delegates.&quot;

What does it mean that you don&#39;t directly own the delegate object? I typically retain my delegates, because if I don&#39;t want them to go away into the abyss, retain will take care of that for me. I usually abstract UITableViewController away from its respective dataSource and delegate also. I also retain that particular object. I want to make sure it never goes away so my UITableView always has its delegate around.

Can someone further explain where/why I&#39;m wrong, so I can understand this common paradigm in Objective-C 2.0 programming of using the assign property on delegates instead of retain?

Thanks!

Why are Objective-C delegates usually given the property assign instead of retain?

Is there an easy way delay a method call for 1 second?

I have a `UIImageView` that reacts on a touch event. When the touch is detected, some animations happen in the app. After one second, I want to call another method. In this case, I can&#39;t use the `animationDidStop` selector.

How can I delay a method call for 1 second?

I want to wobble an image back and forth in my application similar to how the iPhone icons wobble when you press down on it.  What&#39;s the best way to do that?  

This is my first foray into animations that&#39;s not using an animated GIF.  I think the idea is to slightly rotate the image back and forth to create the wobbling effect.  I&#39;ve looked at using CABasicAnimation and CAKeyframeAnimation.  CABasicAnimation creates a jitter every time it repeats because it jumps to the from position and doesn&#39;t interpolate back.  CAKeyframeAnimation seems like the solution except that I can&#39;t get it to work.  I must be missing something.  Here&#39;s my code using the CAKeyframeAnimation (which doesn&#39;t work):

    	NSString *keypath = @&quot;wobbleImage&quot;;
	CAKeyframeAnimation *animation = [CAKeyframeAnimation animationWithKeyPath:keypath];
	animation.duration = 1.0f;
	animation.delegate = self;
	animation.repeatCount = 5;
	
	CGFloat wobbleAngle = 0.0872664626f;
	NSValue *initial = [NSValue valueWithCATransform3D:CATransform3DMakeRotation(0.0f, 0.0f, 0.0f, 1.0f)];
	NSValue *middle = [NSValue valueWithCATransform3D:CATransform3DMakeRotation(wobbleAngle, 0.0f, 0.0f, 1.0f)];
	NSValue *final = [NSValue valueWithCATransform3D:CATransform3DMakeRotation(-wobbleAngle, 0.0f, 0.0f, 1.0f)];
	animation.values = [NSArray arrayWithObjects:initial, middle, final, nil];
	
	[imageView.layer addAnimation:animation forKey:keypath];

&lt;br /&gt;
Or there could be a totally simpler solution that I&#39;m just missing.  Appreciate any pointers.  Thanks!


how to create iphone&#39;s wobbling icon effect?

I have the following simple code to connect to a SSL webpage

    NSMutableURLRequest *urlRequest=[NSMutableURLRequest requestWithURL:url];
	[ NSURLConnection sendSynchronousRequest: urlRequest returningResponse: nil error: &amp;error ];

Except it gives an error if the cert is a self signed one `Error Domain=NSURLErrorDomain Code=-1202 UserInfo=0xd29930 &quot;untrusted server certificate&quot;.` Is there a way to set it to accept connections anyway (just like in a browser you can press accept) or a way to bypass it?

How to use NSURLConnection to connect with SSL for an untrusted cert?

Well, for integers I would use `NSNumber`. But YES and NO aren&#39;t objects, I guess. A.f.a.i.k. I can only add objects to an `NSDictionary`, right?

I couldn&#39;t find any wrapper class for booleans. Is there any?

How can I add a boolean value to a NSDictionary?

The `NSObject` method `performSelector:withObject:afterDelay:` allows me to invoke a method on the object with an object argument after a certain time. It cannot be used for methods with a non-object argument (e.g. ints, floats, structs, non-object pointers, etc.).

What is the *simplest* way to achieve the same thing with a method with a non-object argument? I know that for regular `performSelector:withObject:`, the solution is to use `NSInvocation` (which by the way is really complicated). But I don&#39;t know how to handle the &quot;delay&quot; part.

Thanks,

How to use performSelector:withObject:afterDelay: with primitive types in Cocoa?

This may seem stupid, but I still couldn&#39;t figure out how to mark a attribute as a primary key in the xcdatamodel file.
My persistent storage is sqlite file.
Can anyone help me?

In that case, how can I &quot;validate&quot; a ID to be unique?
Should I write a validation method or something?



Core Data Primary Key

In short: I want to have two fullscreen views, where I can switch between view A and view B. I know I could just use an Tab Bar Controller, but I dont want to. I want to see how this is done by hand, for learning what&#39;s going on under the hood.

I have an UIViewController that acts as an root controller:

    @interface MyRootController : UIViewController {
    	IBOutlet UIView *contentView;
    }
    @property(nonatomic, retain) UIView *contentView;

    @end

The contentView is hooked up to an UIView which I added as an subview to the &quot;view&quot; of the Nib. This has green color and I see it fullscreen. Works fine.

Then, I created two other View Controllers pretty much the same way. ViewControllerA and ViewControllerB. ViewControllerA has a blue background, ViewControllerB has a black background. Just to see which one is active.

So, in the implementation of myRootController, I do this:

    // Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
    - (void)viewDidLoad {
        [super viewDidLoad];

        ViewControllerA *vcA = [[ViewControllerA alloc] initWithNib];
        [self.contentView addSubview:vcA.view];

        [cvA release];
    }

By the way, the -initWithNib method looks like this:

    - (id)initWithNib { // Load the view nib
    	if (self = [super initWithNibName:@&quot;ViewA&quot; bundle:nil]) {
    		// do ivar initialization here, if needed
    	}
    	return self;
    }

That works. I see the view from ViewControllerA when I start the app. But now the big question is: A View Controller typically has all those methods like:

- (void)viewWillAppear:(BOOL)animated;
- (void)viewDidDisappear:(BOOL)animated;
- (void)viewDidLoad;

...and so on. Who or what, or how would those methods be called if I do it &quot;my&quot; way without a tab bar controller? I mean: If I allocate that ViewController&#39;s class and the view get&#39;s visible, would I have to take care about calling those methods? How does it know that viewWillAppear, viewDidDisappear, or viewDidLoad? I believe that the Tab Bar Controller has all this &quot;cleverness&quot; under the hood. Or am I wrong?

UPDATE: I&#39;ve tested it. If I release the view controller (for example: ViewControllerA), I will get no log message on viewDidDisappear. Only when allocating and initializing the ViewControllerA, I get an viewDidLoad. But that&#39;s it. So all signs stand for the cleverness of UITabBarController now ;) and I have to figure out how to replicate that, right?


View Controllers: How to switch between views programmatically?

How can I remove a previously installed development provisioning profile from xcode? 

removing provisioning profile from xcode

I&#39;m looking for a way to completely remove the separator line in a UITableView when in the plain mode. This is done automatically in grouped, but this also changes the dimensions of the table in a way that is hard to measure. I have set the seperator line color to colorClear. But this does not completely solve the problem.

As I am trying to draw a custom background view in the cells, and I want the cells to be seamless, the one pixel line that remains in-between is causing me problems. Is there a more elegant workaround then using a grouped view and then stretching it?

Is there a way to remove the separator line from a UITableView?

I basically need to get current date and time separately, formatted as:

&lt;pre&gt;
2009-04-26 
11:06:54
&lt;/pre&gt;

The code below, from another question on the same topic, generates

&lt;pre&gt;
now:        |2009-06-01 23:18:23 +0100| 
dateString: |Jun 01, 2009 23:18| 
parsed:     |2009-06-01 23:18:00 +0100|
&lt;/pre&gt;

This is almost what I&#39;m looking for, but I want to separate the day and time.

    NSDateFormatter *format = [[NSDateFormatter alloc] init];
    [format setDateFormat:@&quot;MMM dd, yyyy HH:mm&quot;];
    	
    NSDate *now = [[NSDate alloc] init];
    
    NSString *dateString = [format stringFromDate:now];
    	
    NSDateFormatter *inFormat = [[NSDateFormatter alloc] init];
    [inFormat setDateFormat:@&quot;MMM dd, yyyy&quot;];
    
    NSDate *parsed = [inFormat dateFromString:dateString];
    	
    NSLog(@&quot;\n&quot;
    &quot;now:        |%@| \n&quot;
    &quot;dateString: |%@| \n&quot;
    &quot;parsed:     |%@|&quot;, now, dateString, parsed);

Formatting NSDate into particular styles for both year, month, day, and hour, minute, seconds

Edit Feb 2014: **Note that this question dates from iOS 2.0!** Image requirements and handling have moved on a lot since then. Retina makes images bigger and loading them slightly more complex. With the built in support for iPad and retina images, **you should certainly use ImageNamed in your code**.

I see a lot of people saying `imageNamed` is bad but equal numbers of people saying the performance is good - especially when rendering `UITableView`s. See [this SO question][1] for example or [this article][2] on iPhoneDeveloperTips.com 

`UIImage`&#39;s `imageNamed` method used to leak so it was best avoided but has been fixed in recent releases. I&#39;d like to understand the caching algorithm better in order to make a reasoned decision about where I can trust the system to cache my images and where I need to go the extra mile and do it myself. My current basic understanding is that it&#39;s a simple `NSMutableDictionary` of `UIImages` referenced by filename. It gets bigger and when memory runs out it gets a lot smaller.

For example, does anyone know for sure that the image cache behind `imageNamed` does not respond to `didReceiveMemoryWarning`? It seems unlikely that Apple would not do this.

If you have any insight into the caching algorithm, please post it here.


  [1]: https://stackoverflow.com/questions/316236/uiimage-imagenamed-vs-uiimage-imagewithdata
  [2]: http://iphonedevelopertips.com/memory-management/images-and-caching.html

Content Type	Original Author	Original Content on Stackoverflow
Question	Thanks	View Question on Stackoverflow
Solution 1 - Ios	Jarret Hardie	View Answer on Stackoverflow
Solution 2 - Ios	Tibidabo	View Answer on Stackoverflow
Solution 3 - Ios	GilesDMiddleton	View Answer on Stackoverflow
Solution 4 - Ios	Ramin	View Answer on Stackoverflow

How can I add CGPoint objects to an NSArray the easy way?

Ios Problem Overview

Ios Solutions

Solution 1 - Ios

Solution 2 - Ios

Solution 3 - Ios

Solution 4 - Ios

Named Branches vs Multiple Repositories

Why is UnhandledExceptionEventArgs.ExceptionObject an object and not an Exception?

Attributions