UIImagePickerController导航字体颜色和背景

 // 创建图片选择器
            UIImagePickerController *picker = [[UIImagePickerController alloc] init];
            picker.sourceType =UIImagePickerControllerSourceTypePhotoLibrary;
            picker.allowsEditing = YES;
            picker.delegate = self;

             //设置导航栏背景颜色

             picker.navigationBar.barTintColor = HexRGB(0x4294FE);

             //设置右侧取消按钮的字体颜色

             picker.navigationBar.tintColor = [UIColor whiteColor]; // 以富文本方式更改[picker.navigationBar setTitleTextAttributes:@{NSForegroundColorAttributeName:[UIColor whiteColor], NSFontAttributeName:[UIFont boldSystemFontOfSize:18]}];

           [self presentViewController:picker animated:YES completion:nil];

- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated
{
    [viewController.navigationItem.rightBarButtonItem setTitleTextAttributes:@{NSForegroundColorAttributeName:[UIColor whiteColor], NSFontAttributeName:[UIFont systemFontOfSize:18]} forState:UIControlStateNormal];
    
    [viewController.navigationItem.leftBarButtonItem setTitleTextAttributes:@{NSForegroundColorAttributeName:[UIColor whiteColor], NSFontAttributeName:[UIFont systemFontOfSize:18]} forState:UIControlStateNormal];
}