UIBarButtonItem+Todd.h

#import <UIKit/UIKit.h>

@interface UIBarButtonItem (Todd)

@property (assign, nonatomic, getter = isSelected) BOOL selected;

- (instancetype)initWithImageName:(NSString *)imageName target:(id)target selector:(SEL)selector;
- (instancetype)initWithImageName:(NSString *)imageName selectedImageName:(NSString *)selectedImageName target:(id)target selector:(SEL)selector;

@end

UIBarButtonItem+Todd.m

#import "UIBarButtonItem+Todd.h"

@implementation UIBarButtonItem (Todd)

- (UIButton *)createButtonWithImage:(NSString *)imageName selectedImageName:(NSString *)selectedImageName target:(id)target selector:(SEL)selector {
    UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 48, 44)];
    [button setImage:[UIImage imageNamed:imageName] forState:UIControlStateNormal];
    if (selectedImageName) {
        [button setImage:[UIImage imageNamed:selectedImageName] forState:UIControlStateSelected];
    }

    [button addTarget:target action:selector forControlEvents:UIControlEventTouchUpInside];
    
    return button;
}

- (instancetype)initWithImageName:(NSString *)imageName target:(id)target selector:(SEL)selector {
    return [self initWithImageName:imageName selectedImageName:nil target:target selector:selector];
}

- (instancetype)initWithImageName:(NSString *)imageName selectedImageName:(NSString *)selectedImageName target:(id)target selector:(SEL)selector {
    UIButton *button = [self createButtonWithImage:imageName selectedImageName:selectedImageName target:target selector:selector];
    
    return [self initWithCustomView:button];
}

- (BOOL)isSelected {
    return ((UIButton *)self.customView).isSelected;
}

- (void)setSelected:(BOOL)selected {
    ((UIButton *)self.customView).selected = selected;
}

@end

This is an UIBarButtonItem category that helps to make it easy to add a borderless button as a bar button item.

Now added support for selected button state.