The `mom` and `momd` files are compiled versions of `xcdatamodel` and `xcdatamodeld` files.

There information about how the compiling process works [here][1] (page 31). To quote from the docs:

&gt; A data model is a deployment resource. In addition to details of the entities and properties in the model, a model you create in Xcode contains information about the diagram—its layout, colors of elements, and so on. This latter information is not needed at runtime. The model file is compiled using the model compiler, `momc`, to remove the extraneous information and make runtime loading of the resource as efficient as possible.


  [1]: http://www.warrenworks.com/ITP_137/References/CoreData.pdf

I am writing a single page ajax app with ASP.NET MVC - making heavy use of jQuery.  I do something similar to the following throughout the app:

JS:

    $.ajax({
    	type: &quot;GET&quot;,
    	url: &quot;/Home/GetSomePartialView/&quot;,
    	data: someArguments,
    	success: function (viewHTML) { 
    		$(&quot;#someDiv&quot;).html(viewHTML); 
    	},
    	error: function (errorData) { onError(errorData); }
    });

Controller C#:

    public ActionResult GetSomePartialView(SomeArgumentModel someArguments)
    {
    	
    	return PartialView(&quot;_CaseManager&quot;);
    }

This works great.  The `viewHTML` (in the ajax `success` function) is returned as a string and I can shove it on the page no problem.

Now what I would like to do is to return not only the PartialView HTML string, but also some sort of status indicator.  This is a permissions thing - for instance, if someone tries to get to a portion of they app they don&#39;t have permission to, I want to return a different PartialView than they asked for and also display a message in a popup window telling them why they got an View different from what they asked for.

So - to do this, I would like to do the following:

Controller C#:

    public ActionResult GetSomePartialView(SomeArgumentModel someArguments)
    {
    	ReturnArgs r = new ReturnArgs();
    	
    	bool isAllowed = CheckPermissions(); 
    	
    	if (isAllowed) 
    	{
    		r.Status = 400; //good status ... proceed normally
    	    r.View = PartialView(&quot;_CaseManager&quot;);
    	}
    	else
    	{
    		r.Status = 300; //not good ... display permissions pop up
            r.View = PartialView(&quot;_DefaultView&quot;);
    	}
    	
    	return Json(r);
    }

    public class ReturnArgs
    {
    	public ReturnArgs()
    	{
    	}
    
    	public int Status { get; set; }
    	public PartialViewResult View { get; set; }
    }



JS:

    $.ajax({
    	type: &quot;GET&quot;,
    	url: &quot;/Home/GetSomePartialView/&quot;,
    	data: someArguments,
    	success: function (jsReturnArgs) { 
    		
    		if (jsReturnArgs.Status === 300) { //300 is an arbitrary value I just made up right now
    			showPopup(&quot;You do not have access to that.&quot;);
    		}
    	
    		$(&quot;#someDiv&quot;).html(jsReturnArgs.View); //the HTML I returned from the controller
    	},
    	error: function (errorData) { onError(errorData); }
    });



This **SORTA** works right now.  I get a good object in JavaScript (what I am expecting to see), however I cannot see how to get at the full HTML string of the `jsReturnArgs.View` property.  

I am really just looking for the same string that would be returned if I were just returning the `PartialView` by itself.

(As I mentioned at the beginning, this is a single page app - so I can&#39;t just redirect them to another View).

Thanks in advance for any help!

ASP.NET MVC - Returning a PartialView to Ajax along with another object

I read https://stackoverflow.com/questions/3050518/what-http-status-response-code-should-i-use-if-the-request-is-missing-a-required but it did not specifically ask about headers and there didn&#39;t seem to be a consensus.

The context of this question assumes successful authentication.  I&#39;m currently favoring either a 400 (though that doesn&#39;t feel right because this isn&#39;t really a case of &quot;malformed syntax&quot;) or 403.  Given 403&#39;s description:

&gt; The server understood the request, but is refusing to fulfill it.
&gt; Authorization will not help and the request SHOULD NOT be repeated. **If
&gt; the request method was not HEAD and the server wishes to make public
&gt; why the request has not been fulfilled, it SHOULD describe the reason
&gt; for the refusal in the entity.**

This makes the most sense to me.

Can someone please enlighten me?  Thanks.

What is the most appropriate HTTP status code to return if a required header is missing?

I create a Master-Detail application using Core Data. And there is  a simple code to 
get the path for Model file:


    NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@&quot;Model&quot; withExtension:@&quot;momd&quot;];

I have no idea why the extension isn&#39;t &quot;xcdatamodel&quot; but &quot;momd&quot;. 

Does anyone know the answer?



Why the Extension is &quot;momd&quot; but not &quot;xcdatamodel&quot; when search the path for the Model file

I create a Master-Detail application using Core Data. And there is a simple code to
get the path for Model file:
<pre><code class="hljs language-ini">NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@"Model" withExtension:@"momd"];
</code></pre>
I have no idea why the extension isn't "xcdatamodel" but "momd".
Does anyone know the answer?

I am building a mobile application that will target iPhone/iPad and Android phones. The application will involve users taking photos and uploading to my server and later on the users will be able to look at those photos on their mobile devices (although not necessarily their own photos so an Android user might be looking at a photo taken with an iPhone).

Which sizes should I save the photos to be able to cover the most use cases? iPads are 1.333 W/H, most mobile phones are 1.5 or 1.333 W/H with some rare 1.666 W/H. Specifically:

iPad: 1024x768, iPad3: 2048x1536, iPhone and some other phones: 960x640, 480x320, 800x480.

To be able to keep it manageable, I need to decide on a few certain image sizes and save the photos in those sizes. I am not really looking for help on the technical side. I can do image scaling on the server side etc. I am looking for recommendations / best practices / lessons learned about image sizes before I go too far into building it.

* Which sizes should I save the photos in to cover the most use cases?
* Do you recommend any client side scaling before uploading to server to save on transfer time (for example scaling down 2048x1536 iPad photos) or should I always transfer originals?
* How should I handle incompatible image sizes (showing a picture taken with an iPad on an Android device for example)? Should I pre-cut those images on my server before sending to client or should I let the client phone handle image resizing?
* There is also the issue of UI. There will be other things on the page other than the photo maybe a button or two for navigation. Should I go for something smaller than the full screen size while keeping the same aspect ratio when saving pictures?

I know some of these questions don&#39;t have one answer and the answers are relative but I wanted to get some opinions. Thanks.


Image Size Best Practices for Mobile Application

I always get this message when I try to submit my app to the app store.

Here is a picture of the message:

![picture][1]

It would be great if someone could help me resolve that problem so I can submit my app to the store.




  [1]: http://i.stack.imgur.com/0LvhN.png

Xcode &quot;The private key for is not installed on this mac - distributing&quot;

For the past few weeks I&#39;ve been working with images in objective-c and noticing a lot of strange behavior.  First, like many other people, I&#39;ve been having this problem where images taken with the camera (or taken with somebody else&#39;s camera and MMS&#39;d to me) are rotated 90 degrees.  I wasn&#39;t sure why in the world this was happening (hence [my question][1]) but I was able to come up with a cheap work around.  

My question this time is **why is this happening**?  Why is Apple rotating images?  When I take a photo with my camera right-side up, unless I perform my code mentioned above, when I save the photo it gets saved rotated.  Now, my workaround was okay up until a few days ago.  

My application modifies individual pixels of an image, specifically the alpha channel of a PNG (so any JPEG conversion gets thrown out of the window for my scenario).  A few days ago I noticed that even though the image is displayed properly in my app thanks to my workaround code, when my algorithm modifies the individual pixels of the image, it thinks the image is rotated.  So instead of modifying the pixels at the top of the image, it modifies the pixels on the side of the image (because it thinks it should be rotated)!  I can&#39;t figure out how to rotate the image in memory - ideally I would prefer to just wipe away that `imageOrientation` flag all together.


Here&#39;s something else that has been baffling me as well... When I take the photo, the `imageOrientation` is set to 3.  My workaround code is smart enough to realize this and flip it so the user never notices.  Additionally, my code to save the image to the library realizes this, flips it, *then* saves it so it appears in the camera roll properly.  

That code looks like so:

    NSData* pngdata = UIImagePNGRepresentation (self.workingImage); //PNG wrap 
    UIImage* img = [self rotateImageAppropriately:[UIImage imageWithData:pngdata]];   
    UIImageWriteToSavedPhotosAlbum(img, nil, nil, nil);

When I load this newly saved image into my app, the `imageOrientation` is 0 - exactly what I want to see, and my rotation workaround doesn&#39;t even need to run (note: when loading images from the internet as opposed to images taken with a camera, the `imageOrientation` is always 0, resulting in perfect behavior).  For some reason, my save code seems to wipe away this `imageOrientation` flag.  I was hoping to just steal that code and use it to wipe away my imageOrientation as soon as the user takes a photo and has it added to the app, but it doesn&#39;t seem to work.  Does `UIImageWriteToSavedPhotosAlbum` do something special with `imageOrientation`?


Would the best fix for this problem  be to just blow away `imageOrientation` as soon as the user is done taking an image.  I assume Apple has the rotation behavior done for a reason, right?  A few people suggested that this is an Apple defect.  


(... if you&#39;re not lost yet... Note2:  When I take a horizontal photo, everything seems to work perfectly, just like photos taken from the internet)


EDIT:

Here are what some of the images and scenarios actually look like.  Based off the comments so far, it looks like this strange behavior is more than just an iPhone behavior, which I think is good.

This is a picture of the photo I took with my phone (note the proper orientation), it appears exactly as it did on my phone when I snapped the photo:

![Actual Photo taken on iPhone][2]

Here is what the image looks like in Gmail after I emailed it to myself (looks like Gmail handles it properly):

![Photo as it appears in Gmail][3]

Here is what the image looks like as a thumbnail in windows (doesn&#39;t look like it is handled properly):

![Windows Thumbnail][4]

And here is what the actual image looks like when opened with Windows Photo Viewer (still not handled properly):

![Windows Photo Viewer Version][5]

After all of the comments on this question, here&#39;s what I&#39;m thinking... The iPhone takes an image, and says &quot;to display this properly, it needs to be rotated 90 degrees&quot;.  This information would be in the EXIF data.  (Why it needs to be rotated 90 degrees, rather than defaulting to straight vertical, I don&#39;t know).  From here, Gmail is smart enough to read and analyze that EXIF data, and properly display it.  Windows however, is not smart enough to read the EXIF data, and therefore displays the image **improperly**.  Are my assumptions correct?


  [1]: https://stackoverflow.com/questions/10307521/ios-png-image-rotated-90-degrees &quot;my question&quot;
  [2]: http://i.stack.imgur.com/tG0Uf.png
  [3]: http://i.stack.imgur.com/pgIBL.png
  [4]: http://i.stack.imgur.com/S4rsI.png
  [5]: http://i.stack.imgur.com/SZKqC.png

iOS Image Orientation has Strange Behavior

The IOS simulator in my computer doesn&#39;t have app store.  I want to use the app store to test a program I wrote on my simulator.  

Is it possible to install the app store in my simulator?

Can I install the &quot;app store&quot; in an IOS simulator?

Is it possible to use Python to write cross-platform apps for both iOS and Android

Is it possible to use Python to write cross-platform apps for both iOS and Android?

I have added all of the relevant code to the App Delegate, and I am able to add to the data model and fetch from the data model in applicationDidFinishLaunchingWithOptions.

My problem comes when I am trying to write to the data model in my View Controller. I have added this code to the header file:

    NSFetchedResultsController *fetchedResultsController;
    NSManagedObjectContext *managedObjectContext;

    @property (nonatomic, retain) NSFetchedResultsController *fetchedResultsController;
    @property (nonatomic, retain) NSManagedObjectContext *managedObjectContext;

And this code to my implementation file:

    NSManagedObjectContext *context = [self managedObjectContext];
    NSManagedObject *model = [NSEntityDescription
                              insertNewObjectForEntityForName:@&quot;Events&quot; 
                              inManagedObjectContext:context];
    [model setValue:@&quot;Sample Event&quot; forKey:@&quot;eventName&quot;];
    
    NSError *error;
    if (![context save:&amp;error]) {
        NSLog(@&quot;Couldn&#39;t save: %@&quot;, [error localizedDescription]);
    }

However, I get the following error:

    &#39;NSInvalidArgumentException&#39;, reason: &#39;+entityForName: nil is not a legal NSManagedObjectContext parameter searching for entity name &#39;Events&#39;&#39;

Does anyone know what&#39;s going on? Any help would be appreciated.

&#39;+entityForName: nil is not a legal NSManagedObjectContext parameter - Core Data

When should I check &quot;use scalar properties for primitive data types&quot; during creating `NSManagedObject` objects? &lt;br/&gt;
What it will cost me (will my data base improve performance or be more lightweight)?

Core Data &quot;use scalar properties for primitive data types&quot; check box

So, it finally happened. The worst case scenario for any independent iPhone developer occurred. Several users are reporting complete **data loss** after upgrading my app. iCloud Core Data sync is not working. My users are using this app partially to run their businesses. This is a truly *catastrophic failure*.

The only iCloud related thing I changed was to add the key-value store to iCloud. The core data code remained exactly the same, same model version (no migration) etc.

In my tests everything worked beautifully! But to my dismay, users reported that their data was not there anymore when they opened the updated app. 

What could be the reason for this? 

- The *persistent store URL* (an ubiquitous URL) should not have changed. 
- *Merge conflicts* are also unlikely, as this problem should have arisen before the update.
- &lt;strike&gt;Some interference with the new *ubiquitous key-value store* perhaps?&lt;/strike&gt;    
(I have pretty much ruled this out.)

Below please find the code for my managed object model and persistent store. Let me know if you need anything else to assess the problem. 


    - (NSManagedObjectContext *)managedObjectContext {
        
        if (managedObjectContext_ != nil) {
            return managedObjectContext_;
        }
        
        NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator];
        if (coordinator != nil) {
            managedObjectContext_ = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSMainQueueConcurrencyType];
    		[managedObjectContext_ performBlockAndWait:^{
    			[managedObjectContext_ setPersistentStoreCoordinator:coordinator];
    			if (useICloud) {
    				[managedObjectContext_ setMergePolicy:NSMergeByPropertyObjectTrumpMergePolicy];
    				[[NSNotificationCenter defaultCenter] addObserver:self
               selector:@selector(mergeiCloud:)
               name:NSPersistentStoreDidImportUbiquitousContentChangesNotification
               object:coordinator];
    			}
    		}];
        }
        return managedObjectContext_;
    }

and 

    - (NSPersistentStoreCoordinator *)persistentStoreCoordinator {
        if (persistentStoreCoordinator_ != nil) {
            return persistentStoreCoordinator_;
        }
    
    	NSMutableDictionary *options = [NSMutableDictionary dictionary];
    	NSURL *storeURL = [[self applicationDocumentsDirectory] 
                URLByAppendingPathComponent:@&quot;SalesCalls.sqlite&quot;];
        
    	[options setObject:[NSNumber numberWithBool:YES] 
                      forKey:NSMigratePersistentStoresAutomaticallyOption];
    	[options setObject:[NSNumber numberWithBool:YES] 
                      forKey:NSInferMappingModelAutomaticallyOption];
    	
    	if (useICloud) {  // this is an internal flag set to YES
    		NSURL *iCloudURL = [[NSFileManager defaultManager] 
                                   URLForUbiquityContainerIdentifier:nil];
    		
    		if (nil!=iCloudURL) {
    			NSString *cloudData = [[iCloudURL path] 
                           stringByAppendingPathComponent:@&quot;data&quot;];
    			iCloudURL = [NSURL fileURLWithPath:cloudData];		
    			
    			[options setObject:@&quot;at.topofmind.salesplus.store&quot; 
                            forKey:NSPersistentStoreUbiquitousContentNameKey];
    			[options setObject:iCloudURL 
                            forKey:NSPersistentStoreUbiquitousContentURLKey];
    			
    			NSURL *nosyncDir = [iCloudURL 
                            URLByAppendingPathComponent:@&quot;data.nosync&quot;];
    			[[NSFileManager defaultManager] createDirectoryAtURL:nosyncDir 
                            withIntermediateDirectories:YES 
                            attributes:nil error:nil];
    
    			storeURL = [nosyncDir 
                            URLByAppendingPathComponent:@&quot;SalesCalls.sqlite&quot;];
    		}
    	}
        
        NSError *error = nil;
        persistentStoreCoordinator_ = [[NSPersistentStoreCoordinator alloc] 
                 initWithManagedObjectModel:[self managedObjectModel]];
    	if (![persistentStoreCoordinator_ 
                      addPersistentStoreWithType:NSSQLiteStoreType
                      configuration:nil URL:storeURL options:options error:&amp;error]) 
       {
    		NSLog(@&quot;Cannot create persistent store coordinator, %@, %@&quot;, 
                            error, [error userInfo]);
    		abort();
        }    
        
        return persistentStoreCoordinator_;
    }

Comments, opinions, wild guesses etc. (and of course solutions!) are all welcome. 

**UPDATE:** 

One of my customers lost all his data and after reinstalling and resetting everything (rebooting device, etc.) he could not sync with iCloud any more. The symbol simply does not show up in the Settings.

More iCloud Core Data synching woes

I&#39;m new to iOS. I&#39;ve been trying to make an application that will store an image captured from the camera into `CoreData`. I now know how to store data like `NSString`s, `NSDate` and other type but struggling to store an image. I&#39;ve read so many articles saying you must write it to the disk and write to a file, but I can&#39;t seem to understand it.

The following code is the one i used to store other data to core data.


    - (IBAction)submitReportButton:(id)sender
    {
        UrbanRangerAppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];
        
        managedObjectContext = [appDelegate managedObjectContext];
        
        NSEntityDescription *entity = [NSEntityDescription entityForName:@&quot;PotholesDB&quot; inManagedObjectContext:appDelegate.managedObjectContext];
        NSManagedObject *newPothole = [[NSManagedObject alloc]initWithEntity:entity insertIntoManagedObjectContext:managedObjectContext];
        
           
        [newPothole setValue:self.relevantBody.text forKey:@&quot;relevantBody&quot;];
        [newPothole setValue:self.subjectReport.text forKey:@&quot;subjectReport&quot;];
        [newPothole setValue:self.detailReport.text forKey:@&quot;detailReport&quot;];
    //    [newPothole setValue:self.imageView forKey:@&quot;photo&quot;];
    
        NSDate *now = [NSDate date];
        //NSLog(@&quot;now : %@&quot;, now);
        NSString *strDate = [[NSString alloc] initWithFormat:@&quot;%@&quot;, now];
        NSArray *arr = [strDate componentsSeparatedByString:@&quot; &quot;];
        NSString *str;
        str = [arr objectAtIndex:0];
        NSLog(@&quot;now : %@&quot;, str);
        
        [newPothole setValue:now forKey:@&quot;photoDate&quot;];
        [newPothole setValue:self.latitudeLabel.text forKey:@&quot;latitude&quot;];
        [newPothole setValue:self.longitudeLabel.text forKey:@&quot;longitude&quot;];
        [newPothole setValue:self.addressLabel.text forKey:@&quot;streetName&quot;];
        [newPothole setValue:streeNameLocation forKey:@&quot;location&quot;];
        
        
        NSError *error;
        [managedObjectContext save:&amp;error];
        
        UIAlertView *ll = [[UIAlertView alloc] initWithTitle:@&quot;Saving&quot; message:@&quot;Saved data&quot; delegate:nil cancelButtonTitle:@&quot;OK&quot; otherButtonTitles:nil];
        
        [ll show];
    } 

How to store an image in core data

I&#39;m preparing an update for a Core Data based app for fixes with iOS 7. I use Xcode 5 and iOS 7 SDK GM. However I realized a different behavior of the persistent store (which is a `UIManagedDocument`): Prior to iOS 7 builds there was only one file `persistentStore` in the documents folder (sometimes there was a second one `persistentStore-journal`).

In iOS 7 builds (clean installation) there are now three files for the persistent store:

 - `persistentStore`
 - `persistentStore-wal` and
 - `persistentStore-shm`

Did Apple change the journal mode by default to WAL now? I wonder if there is an impact on my app (think of users how update from the last version)? Would it be best to disable WAL - and if so, how can I do this with iOS 7/`UIManagedDocument`?

Content Type	Original Author	Original Content on Stackoverflow
Question	VIRGIL	View Question on Stackoverflow
Solution 1 - Ios	Amy Worrall	View Answer on Stackoverflow

Why the Extension is "momd" but not "xcdatamodel" when search the path for the Model file

Ios Problem Overview

Ios Solutions

Solution 1 - Ios

What is the most appropriate HTTP status code to return if a required header is missing?

ASP.NET MVC - Returning a PartialView to Ajax along with another object

Attributions