如何在Cocoa中打印控件层次结构？

#import <Cocoa/Cocoa.h>

void printViewHierarchy(NSView *view, NSInteger level) {
    NSMutableString *indentation = [NSMutableString string];
    for (NSInteger i = 0; i < level; i++) {
        [indentation appendString:@"  "];
    }
    
    NSLog(@"%@%@", indentation, view);
    
    for (NSView *subview in view.subviews) {
        printViewHierarchy(subview, level + 1);
    }
}

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        NSView *rootView = [[NSApplication sharedApplication] mainWindow].contentView;
        printViewHierarchy(rootView, 0);
    }
    return 0;
}