导航栏设置为透明色后变成了黑色 #86

AXWebViewController *webVC = [AXWebViewController sharedManagerWithUrl:@"http://www.baidu.com"];
    webVC.enabledWebViewUIDelegate = YES;
    webVC.showsToolBar = NO;
    webVC.showsBackgroundLabel = NO;
    if (AX_WEB_VIEW_CONTROLLER_iOS9_0_AVAILABLE()) {
        webVC.webView.allowsLinkPreview = YES;
    }
    webVC.navigationType = AXWebViewControllerNavigationBarItem;
    UINavigationController *nav = [[UINavigationController alloc]initWithRootViewController:webVC];
    webVC.navigationController.navigationBar.translucent = NO;
    webVC.navigationController.navigationBar.barTintColor = [UIColor clearColor];
    webVC.navigationController.navigationBar.tintColor = [UIColor clearColor];
    
    self.window = [[UIWindow alloc] init];
    self.window.backgroundColor = [UIColor whiteColor];
    self.window.frame = [UIScreen mainScreen].bounds;
    self.window.rootViewController = nav;
    [self.window makeKeyAndVisible];