UINavigationItem不显示

效果如图：

代码：

self.navigationItem.leftBarButtonItem = [UIBarButtonItem itemWithNormalImage:@"MainTagSubIcon" hignlightImage:@"MainTagSubIconClick" target:self action:@selector(leftButtonClick)];

+ (instancetype)itemWithNormalImage:(NSString *)normalImage hignlightImage:(NSString*)hignlightImage target:(id)target action:(SEL)action{

UIButton *buttonItem = [UIButton buttonWithType:UIButtonTypeCustom];

[buttonItem setImage:kImage(normalImage) forState:UIControlStateNormal];

[buttonItem setImage:kImage(hignlightImage) forState:UIControlStateHighlighted];

[buttonItem addTarget:target action:action forControlEvents:UIControlEventTouchUpInside];

return [[self alloc]initWithCustomView:buttonItem];

}

原因：customView没有指定尺寸（位置不用指定）

加了句：

buttonItem.size = buttonItem.currentImage.size;

效果如图：