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How to determine if a property is IBOutlet software at runtime?

I install unit tests in my project to make sure that all UIViewController IBOutlets are connected to their respective Xib objects (ie, not zero after viewDidLoad.) I was considering applying a protocol to these UIViewControllers with the required function "getAllOutletNames", for example:

-(NSArray*)getAllOutletNames
{
    return @[ @"outletproperty1", @"outletProperty2", ...];
}

... and then using [viewController valueForKey: outletName] to make sure none of them are null. The problem is that it is a little cumbersome; "getAllOutletNames" needs to be updated for each output added to xib, which can be easily overlooked. I would prefer to do this programmatically so that all the properties of IBOutlet can be automatically detected and repeated.

I read in this NSHipster article (cmd + f for attributes with an attribute) that the attribute applies to IBOutlets (or, an attribute supported by an attribute that I don't quite understand.)

It looks like I can get a list of all the properties in the class using part of this answer , and I can get their attributes using part of this answer . But, printing the attributes from IBOutlet and non-IBOutlet properties using the following code, I see no difference:

const char * type = property_getAttributes(class_getProperty([self class], [outletName UTF8String]));
NSString * typeString = [NSString stringWithUTF8String:type];
NSArray * attributes = [typeString componentsSeparatedByString:@","];
NSLog(@"%@",attributes);

IBOutlet

(
    "T@\"UILabel\"",
    "&",
    N,
    "V_titleLabel"
)

Non-iboutlet

(
    "T@\"UIView\"",
    "&",
    N,
    "V_programmaticallySetupView"
)

Is there a way to access this attribute, supported by the attribute that NSHipster mentioned in the article or otherwise determined whether the property is IBOutlet software programmatically, or am I taking the wrong tree here?

+4
1

, , , :

#import <objc/runtime.h>

#define synthesize_nooutlet(name) \
synthesize name=_ ## name;        \
- (oneway id)name {               \
  return _ ## name;               \
}

@interface ViewController ()

@property (nonatomic, strong) UIView *theView;

@end

@implementation ViewController

@synthesize_nooutlet(theView);

- (void) viewDidLoad {

  [super viewDidLoad];

  [self.theView setBackgroundColor:[UIColor clearColor]];

  char returnType;
  method_getReturnType(class_getInstanceMethod([self class], @selector(theView)), &returnType, 1);
  if (returnType == 'V') {
    // Do stuff
  }
}

@end

- , :

https://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/ObjCRuntimeGuide/Articles/ocrtTypeEncodings.html#//apple_ref/doc/uid/TP40008048-CH100-BABHAIFA

, , iOS, .

+1

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