key-value-coding
Getting the maximum value from dictionary
I\'m facing problem with this. I have 10,000 rows in my dictionary and this is one of the rows Example: A (8) C (4) G (48419) T (2) when printed out[详细]
2023-02-08 19:02 分类:问答Directly accessing nested dictionary values in Objective-C
Is there a way to directly access an inner-array of an an outer array in Objective-C?For example, a call to an external data source returns the following object:[详细]
2023-01-27 10:59 分类:问答What's the point of -primitiveValueForKey:?
-setPrimitiveValue:forKey: won\'t trigger KVO notifications. But in my brain, KVO only makes sense when something changes. But how can change开发者_Go百科 something when I only access it for read?[详细]
2023-01-24 04:44 分类:问答Defining your own key path operators in cocoa
Is it possible to define your own key path operators, such as @avg开发者_运维问答, @sum, etc…Short answer: Kinda. You can override valueForKeyPath: to intercept your custom operator or forward on to[详细]
2023-01-23 19:20 分类:问答ExecuteFetchRequest intermittently throwing exception with same parameters. "not key value coding-compliant for the key"
EDIT Thanks to Matt\'s post I now understand that I should not be trying to access \'started\' as an array.However, if that is the case, I would like to know why this code appears to be working in oth[详细]
2023-01-23 15:02 分类:问答Carry out action when multiple properties change
I have three different properties, x, y, z. If they all turn nil, I need to take an action, and if one of them is set to a value != nil, I have to carry out a different action.[详细]
2023-01-21 04:14 分类:问答Core Data: Two Different Ways to Access Attributes, Only One Works
For the following code, of the two comment preceded lines below, only the first works. NSManagedObject * Event = [NSEntityDescription insertNewObjectForEntityForName:str inManagedObjectContext:app.m[详细]
2023-01-19 18:35 分类:问答Observing the editing property of a UITableViewController
Why can\'t I observe the editing property of an instance of UITableViewController? I\'m using the following code:[详细]
2023-01-18 03:52 分类:问答add<Key>Object vs insertNewObjectForEntityForName Core Data Relationships
Hi, Although I have a lot of experience in database development, I\'m having a hard time conceptualizing linking relationships in Core Data. As I understand it, the many relationship is an NSSet at[详细]
2023-01-15 23:10 分类:问答KVC string conversion not working for BOOL value
Hey.I am reading in a string from a file and attempting to use the resulting string to set a BOOL property on an object using the KVC method -setValue:forKeyPath:.However, this breaks with an exceptio[详细]
2023-01-15 00:08 分类:问答