通过继承封装导航栏,使导航栏上面出现的按钮和图标均相同

<pre name="code" class="objc"><p>当我们做多个导航控制器 我们需要自定义返回按钮 每次都要写大量的代码 </p><p>既浪费了时间 也没有从根本上解决我们的问题 </p><p>我们需要的功能是实现页面间的返回 并且右上角的按钮点击之后 可以直接返回到主页减少代码</p><p>为了减少代码 我们可以选择继承 </p><p>这是一种解决方法 </p><p>但是不建议大家这样做 因为apple 为我们提供的控制器太多了 </p><p>不一定都是UIViewController  ,有UITableViewController UICollectionVIewController 如果我们通过继承 那么当UITableViewController 改为继承UIVIewController 那就出大问题了 本来有tableView 单继承下来就会报错 </p><p>下面给出一个例子 用于 一般的 </p><p>#import "QHBaseViewController.h"</p>@interface QHBaseViewController ()@end@implementation QHBaseViewController- (void)viewDidLoad {    [super viewDidLoad];    //设置图片    UIButton *backBtn = [UIButton buttonWithType:UIButtonTypeCustom];    [backBtn addTarget:self action:@selector(back) forControlEvents:UIControlEventTouchUpInside];    [backBtn setBackgroundImage:[UIImage imageNamed:@"navigationbar_back"] forState:UIControlStateNormal];    [backBtn setBackgroundImage:[UIImage imageNamed:@"navigationbar_back_highlighted"] forState:UIControlStateHighlighted];    //设置尺寸    backBtn.size = backBtn.currentBackgroundImage.size;    //这时一个自定义的方法        self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc]initWithCustomView:backBtn];    UIButton *moreBtn = [UIButton buttonWithType:UIButtonTypeCustom];    [moreBtn addTarget:self action:@selector(more) forControlEvents:UIControlEventTouchUpInside];    [moreBtn setBackgroundImage:[UIImage imageNamed:@"navigationbar_more"] forState:UIControlStateNormal];    [moreBtn setBackgroundImage:[UIImage imageNamed:@"navigationbar_more_highlighted"] forState:UIControlStateHighlighted];    moreBtn.size = moreBtn.currentBackgroundImage.size;        self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc]initWithCustomView:moreBtn];    // Do any additional setup after loading the view.}-(void)back{    [self.navigationController popViewControllerAnimated:YES];}-(void)more{    [self.navigationController popToRootViewControllerAnimated:YES];}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}/*#pragma mark - Navigation// In a storyboard-based application, you will often want to do a little preparation before navigation- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {    // Get the new view controller using [segue destinationViewController].    // Pass the selected object to the new view controller.}*/@end