Custom UIBarButtonItem for UIToolbar
<p>In my testing project, I am planning to have multiple picker views. For these picker views, there will be UIToolbars and custom UIBarButtons. I tried to create a class method so that I will not have to repeat the codes, but it seems like the button is not showing up.</p>

<p><strong>Picker Done Button.h</strong></p>

<pre><code>#import &lt;UIKit/UIKit.h&gt;

@interface UIBarButtonItem (test)
+ (UIBarButtonItem*)barButtonItemWithTint:(UIColor*)color andTitle:(NSString*)itemTitle andTarget:(id)theTarget andSelector:(SEL)selector;
@end
</code></pre>

<p><strong>Picker Done Button.m</strong></p>

<pre><code>#import "PickerDoneButton.h"

@implementation UIBarButtonItem (test)
+ (UIBarButtonItem*)barButtonItemWithTint:(UIColor*)color andTitle:(NSString*)itemTitle andTarget:(id)theTarget andSelector:(SEL)selector
{
    UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
    button.tintColor = color;
    button.backgroundColor = [UIColor yellowColor];
    [button addTarget:theTarget action:selector forControlEvents:UIControlEventValueChanged];
    UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithCustomView:button];
    return doneButton;
}
@end
</code></pre>

<p>And to use this class method on my View Controller.m (I am omitting picker view methods which come after viewDidLoad)</p>

<pre><code>#import "ViewController.h"
#import "PickerDoneButton.h"

@interface ViewController ()
@property (strong, nonatomic) NSArray *numberofPeople;
@property (strong, nonatomic) UIPickerView *countPeople;
@end

@implementation ViewController
- (void)viewDidLoad {
    [super viewDidLoad];
    self.countPeople = [[UIPickerView alloc] init];
    self.countPeople.dataSource = self;
    self.countPeople.delegate = self;
    self.numberofPeople = @[@"1",@"2",@"3"];

    UIToolbar *countPeopleToolbar = [[UIToolbar alloc] initWithFrame:CGRectMake(0,0,0,50)];
    countPeopleToolbar.barStyle = UIBarStyleBlackOpaque;
    // Call the UIBarButtonItem from PickerDoneButton.h
    countPeopleToolbar.items = @[[UIBarButtonItem barButtonItemWithTint:[UIColor redColor] andTitle:@"Done" andTarget:self andSelector:@selector(doneClicked)]];
    [self pickerView:self.countPeople didSelectRow:0 inComponent:0];
}
</code></pre>

<p>Am I using the class method correctly?</p>