Can't see Swift object hierarchy in debug area when used within Objective-C class

Question

My problem may be so simple but I'm so lost in it. Any comment, idea, help, prediction would be so useful.

Here are my classes

TrialSwiftClass.swift

import Foundation

@objc public class TrialSwiftClass : NSObject{
    var first : String?
    var second : NSString?
    var third : NSNumber = 0


    override init(){
        super.init()
    }

    init(data:NSArray){

            self.first = data[0] as? String
            self.second = data[1] as? NSString
            self.third = data[2] as! NSNumber
    }
}

TrialObjectiveCClass.h

#import <Foundation/Foundation.h>

@interface TrialObjectiveCClass : NSObject

@property (nonatomic, strong) NSString *first;
@property (nonatomic, strong) NSString *second;
@property (nonatomic, assign) NSNumber *third;

- (instancetype)initWithArray:(NSArray *)data;

@end

TrialObjectiveCClass.m

#import "TrialObjectiveCClass.h"

@implementation TrialObjectiveCClass


- (instancetype)initWithArray:(NSArray *)data{
    self.first = data[0];
    self.second = data[1];
    self.third = data[2];

    return self;
}
@end

Now here comes the problem.When I use these two classes in my ViewController.m which has following code in it:

#import "ViewController.h"
#import "TrialObjectiveCClass.h"
#import "Codemaster-Swift.h" //Automatically created header to use Swift code in Objective-C


@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    NSArray *trialArray = @[@"FirstString", @"SecondString", @99];


    //First the Swift part
    TrialSwiftClass *obj = [[TrialSwiftClass alloc] initWithData:trialArray];

    NSLog(@"%@", obj.first);
    NSLog(@"%@", obj.second);
    NSLog(@"%@", obj.third);


    //Now the Objective-C part
    TrialObjectiveCClass *obj2 = [[TrialObjectiveCClass alloc] initWithArray:trialArray];
    NSLog(@"%@", obj2.first);
    NSLog(@"%@", obj2.second);
    NSLog(@"%@", obj2.third);


}

If I put a breakpoint in the last NSLog in ViewController.m, here is what i see in debug area:

My logs are showing the right value of my object's properties.

Why can't i see the hierarchy of my Swift class but can see my Objective-C class? How to solve this problem?

Answer 1

The variables in your Swift class get exposed to ObjC as properties. At present the Locals view does not show the properties of an object, only its ivars. This is true regardless of whether the class comes from ObjC or Swift. That's why the swift variables don't show up in the locals view.

You can work around this by using the expression command in the lldb console to view the object's properties. For instance, stopped in your example, you can do:

(lldb) expr obj.first
(__NSCFConstantString *) $0 = 0x00000001002d1498 @"FirstString"

etc.