Key Value Coding is a mechanism for accessing an object’s properties indirectly, using strings to identify properties, rather than through invocation of an accessor method or accessing them directly through instance variables.
References
Questions tagged [kvc]
193 questions
2
votes
1 answer
Objective-C - How does KVC work under the hood?
I am working with KVC and I am wondering how it works under the hood.
Since it uses keys and values, I could assume that the self of each object holds a dictionary with keys = properties name and values = setters . So when I call [self…
BlackM
- 3,927
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2
votes
3 answers
How can I use KVC Collection Operators for distinctUnionOfObjects in NSArray of NSDictionaries?
I want to get the Collection of a Specific Property from an array dictionary which has an array of values. Following is my array NSDictionaries:
NSArray *arrGroupsFromServer= @[
@{@"Id": @"7d1021ba-e9be-40c1-a0a1-ad2a2d185b74",@"Name":…
BhavikKama
- 8,566
- 12
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- 164
2
votes
1 answer
Swift: Boolean attributes and KVC mysteries
So I'm playing with this simple CoreData entity
import CoreData
class Figure: NSManagedObject {
@NSManaged var approx: NSNumber? // Defined as Boolean type without default value
}
As you would expect, for a new figure, you get
figure.approx #…
Arnaud
- 17,268
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2
votes
1 answer
Can't get value from Google-Books JSON API
I'm using a bar code scanner to get data on a scanned book using the google books api. I successfully call the API and get a JSON object back.
I'm trying to get the book title which follows the path items.volumeInfo.title.
When I call valueForPath…
nhyne
- 405
- 1
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- 18
2
votes
1 answer
Prefer property-accessor or KVC style for accessing Core Data properties
I have read the iOS-related chapters of Marcus S. Zarra's Core Data: Data Storage and Management for iOS, OS X, and iCloud (2nd edition) to great benefit. I am wondering about one aspect, though, where the book suggests a style that is different…
Drux
- 11,992
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- 66
- 116
2
votes
1 answer
Detect if at least one property of object was modified
I have class with many strings and mutable arrays. All this objects represent form data. So if I modify textfield or add new photo to array I keep this data in my properties of object.
How can I create validator that will check if some of that…
Matrosov Oleksandr
- 25,505
- 44
- 151
- 277
2
votes
1 answer
Observing on NSMutableArray - Only Array accessors to be used
I have a mutable array which I have exposed in interface. I have also exposed the array accessors to modify the array. If any modification happens within the array, I would have to reset and re-calculate some data using KVO. To support KVO, I am…
Raj Pawan Gumdal
- 7,390
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2
votes
3 answers
Restkit Mapping - No response descriptors match the response loaded
I'm new to RestKit and Objective C. I'm trying to retrieve data from a Web Service with RestKit. I have done the mapping but some how I'm getting the error that it could not find a match for the response. I am using Mapping without KVC as the JSON…
greenhatman
- 76
- 1
- 7
2
votes
3 answers
NSMutableDictionary from NSMutableArray using KVC
I have an Input Array of Dictionaries :
myArray = (
{
name:"abc";
time:"6:00";
},
{
name:"xyz";
time:"7:00";
},
.
.
)
I want Output Dictionary like this :
myDictionary = {
"6:00":(
…
Bhavin
- 27,155
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- 94
2
votes
1 answer
MagicalRecord sorting using by KVC
I used KVC until now to access object's properties.
In my object i have a method like this:
-(Address *)mainAddress {
if (self.addresses != nil) {
return [self.addresses anyObject]; //stub method
}
else {
return nil;
…
IgnazioC
- 4,554
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2
votes
4 answers
Custom class NSObject not key value coding compliant
Possible Duplicate:
Why is my object not key value coding-compliant?
I'm having a dictionary and I want to add keys/values to a custom class, but i always get the error, that the class is not KVC compliant, but the Apple documents state that it…
matttrakker
- 204
- 3
- 15
2
votes
2 answers
Remove UIColor CGColor - KVC warning
How to remove [[UIColor grayColor] CGColor] stupid warning?
[self setValue:
[[UIColor grayColor] CGColor]
forKeyPath:[NSString stringWithFormat:@"_View_%@%d.layer.borderColor",
i>=10?@"":@"0", i]];
Incompatible…
elp
- 8,021
- 7
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- 120
2
votes
1 answer
How to return a primitive property value with CALayer's "+ (id) defaultValueForKey", etc?
So.. CALayer KVC "extensions" handle all the weirdo's... such as..
+ (id) defaultValueForKey: (NSString*)key {
return [key isEqualToString:@"borderColor"]
? (id)cgPINK
: [super defaultValueForKey:key]; }
And Apple's Docs…
Alex Gray
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2
votes
1 answer
[myArray objectAtIndex:i].property in kvc
Anybody know the kvc key/key path fore this code
[myArray objectAtIndex:i].property
Johnykutty
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2
votes
1 answer
Core Data - Why does the object data stays fault even after accessing the property?
I'm using Core Data and i have a managed object that the description states its data is fault.
I try to access a property with dot syntax but it's nil.
If I use -[object valueForKey:@"key"]; the object fires fault and I get the correct value.
from…
Or Arbel
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