如何在ios7.0中更改leftbarbuttonitem颜色

我已经做了上面的工作，但它不起作用。颜色仍然和背景色一样

创建按钮并替换

    self.navigationItem.leftBarButtonItem.tintColor = [UIColor whiteColor];

或

文本颜色：

+ (UIBarButtonItem*)itemWithNormalImage:(UIImage*)normalImage
                           pressedImage:(UIImage*)pressedImage
                                 target:(id)target
                                 action:(SEL)action
{
    UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
    [button setImage:normalImage
            forState:UIControlStateNormal];
    [button setImage:pressedImage
            forState:UIControlStateSelected];
    [button setImage:pressedImage
            forState:UIControlStateHighlighted];

    button.frame = CGRectMake(0, 0, normalImage.size.width, normalImage.size.height);
    [button addTarget:target action:action forControlEvents:UIControlEventTouchUpInside];
    UIBarButtonItem* item=[[UIBarButtonItem alloc] initWithCustomView:button];
    return item;
}

---

创建按钮并替换

    self.navigationItem.leftBarButtonItem.tintColor = [UIColor whiteColor];

或

文本颜色：

+ (UIBarButtonItem*)itemWithNormalImage:(UIImage*)normalImage
                           pressedImage:(UIImage*)pressedImage
                                 target:(id)target
                                 action:(SEL)action
{
    UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
    [button setImage:normalImage
            forState:UIControlStateNormal];
    [button setImage:pressedImage
            forState:UIControlStateSelected];
    [button setImage:pressedImage
            forState:UIControlStateHighlighted];

    button.frame = CGRectMake(0, 0, normalImage.size.width, normalImage.size.height);
    [button addTarget:target action:action forControlEvents:UIControlEventTouchUpInside];
    UIBarButtonItem* item=[[UIBarButtonItem alloc] initWithCustomView:button];
    return item;
}