不是每个界面都写一遍
UIImage image = [UIImage imageNamed:imagePath];
UIButton button = [UIButton buttonWithType:UIButtonTypeCustom];
button.frame = CGRectMake(0.0, 0.0, image.size.width, image.size.height);
[button setImage:image forState:UIControlStateNormal];
[button setImage:[UIImage imageNamed:highLightImagePath] forState:UIControlStateHighlighted];
[button addTarget:self action:selector forControlEvents:UIControlEventTouchUpInside];
self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:button];
能不能有一个统一的方法统一设置?