自定义navigationbar

 

   UINavigationBar *bar = [[UINavigationBar alloc] initWithFrame:CGRectMake(0, 0, kDeviceWidth, 64)];

    [bar setBackgroundImage:[UIImage imageNamed:@"blackbg"] forBarMetrics:UIBarMetricsDefault];

    UINavigationItem *item = [[UINavigationItem alloc] init];

    

    UIButton *backBarButton=[[UIButton alloc] initWithFrame:CGRectMake(0, 7, 30, 30)];

    [backBarButton setBackgroundImage:[UIImage imageNamed:@"nav_back"] forState:UIControlStateNormal];

    backBarButton.showsTouchWhenHighlighted=YES;

    [backBarButton addTarget:self action:@selector(backAction:) forControlEvents:UIControlEventTouchUpInside];

    

    UIBarButtonItem *backItem=[[UIBarButtonItem alloc] initWithCustomView:backBarButton];

    item.leftBarButtonItem = backItem;

    [bar pushNavigationItem:item animated:NO];

    [self.view addSubview:bar];

    

    UILabel * titleLabel=[[UILabel alloc]initWithFrame:CGRectMake(0, 0, 100, 44)];

    titleLabel.backgroundColor=[UIColor clearColor];

    titleLabel.font=[UIFont systemFontOfSize:18];

    titleLabel.text=@"Etcast";

    titleLabel.textAlignment=NSTextAlignmentCenter;

    titleLabel.textColor=[UIColor whiteColor];

    item.titleView=titleLabel;