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POIn Objective-C, how do you set up properties of properties, i.e. of a class set up as another class property?
 

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  1. POIn Objective-C, how do you set up properties of properties, i.e. of a class set up as another class property?
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    <p>I have been trying to set up an instance property of a class which is itself a class that contains instance variables. I would like to access these as properties. In C#, this is easy to do with the pre-set get and set variables:</p> <pre><code>public class TheOverallClass { private ClassName _propertyName; public ClassName PropertyName { get { return _propertyName; } set { _propertyName = value; } } </code></pre> <p>...and PropertyName being instantiated within the constructor:</p> <pre><code> public TheOverallClass() { PropertyName = new ClassName(); } } </code></pre> <p>Say PropertyName had an instance variable/property named ThisValue, I could then access it as:</p> <pre><code>TheOverallClass overallClass = new TheOverallClass(); overallClass.PropertyName.ThisValue = 20; // int Console.WriteLine(overallClass.PropertyName.ThisValue.ToString()); </code></pre> <p>How would I go about doing this in Objective-C? I have had a go, but have run into difficulty.</p> <p>The PropertyName equivalent is coded as:</p> <p>... in AnotherClass.h:</p> <pre><code>@interface AnotherClass : NSObject { int thisValue; } @property (readwrite,assign) int ThisValue; @end </code></pre> <p>... and in AnotherClass.m</p> <pre><code>@implementation AnotherClass @synthesize ThisValue=thisValue; @end </code></pre> <p>This is then used in the ClassName equivalent, MyClass:</p> <p>... in MyClass.h:</p> <pre><code>@class AnotherClass; @interface MyClass : NSObject { AnotherClass* another; } @property (nonatomic,retain) AnotherClass* Another; @end </code></pre> <p>... and in MyClass.m:</p> <pre><code>@implementation MyClass @synthesize Another=another; @end </code></pre> <p>When I try to get/set values within code, Xcode returns "Accessing unknown 'ThisValue' component of a property". The code I use to access is:</p> <pre><code>MyClass* me = [[MyClass alloc] init]; me.Another.ThisValue = 20; NSLog(@"Value = %i", me.Another.ThisValue); </code></pre> <p>What am I doing wrong?</p>
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    1. USkiamlaluno
    1. USBWHazel
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    1. COJust a comment, but you should respect the coding conventions, i.e. make properties begin with *lower* letters.
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      1. POIn Objective-C, how do you set up properties of properties, i.e. of a class set up as another class property?
      1. USEiko
    2. COCheck MyClass.m is including AnotherClass.h.
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      1. POIn Objective-C, how do you set up properties of properties, i.e. of a class set up as another class property?
      1. USkiamlaluno
 

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