IOS UI 自定义navigationBar布局

//1. 配置navigationBar背景图片
[self.navigationController.navigationBar setBackgroundImage:[UIImage
imageNamed:@"header_bg.png" ]
forBarMetrics:UIBarMetricsDefault];

//2.配置中间标题为图片
UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 60, 35)];
imageView.image = [UIImage imageNamed:@"logo_title.png"];
self.navigationItem.titleView=imageView;

UIBarButtonItem *textItem = [[UIBarButtonItem alloc] initWithTitle:@"分类"
style:UIBarButtonItemStylePlain target:self
action:@selector(dealConfig:)];

UIBarButtonItem *systemItem = [[UIBarButtonItem alloc]
initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self
action:@selector(dealConfig:)];

UIButton *leftButton = [UIButton buttonWithType:UIButtonTypeCustom];

leftButton.frame = CGRectMake(0, 0, 45, 30);

[leftButton setBackgroundImage:[UIImage imageNamed:@"photo_left_nav.png"] forState:UIControlStateNormal];

[leftButton addTarget:self action:@selector(dealConfig:) forControlEvents:UIControlEventTouchUpInside];

UIBarButtonItem *leftItem = [[UIBarButtonItem alloc] initWithCustomView:leftButton];

self.navigationItem.leftBarButtonItem = leftItem;
self.navigationItem.rightBarButtonItem = rightItem;