使用WKWebView加载本地pdf

- (void)viewDidLoad {
    [super viewDidLoad];
    WKWebView *webView = [[WKWebView alloc] initWithFrame:self.view.bounds];
    NSURL *pdfUrl = [NSURL URLWithString:[[NSBundle mainBundle] pathForResource:@"hello" ofType:@"pdf"]];
//    NSURL *pdfUrl = [NSURL URLWithString:@"http://www.taobao.com"];
    NSURLRequest *request = [NSURLRequest requestWithURL:pdfUrl];
    [webView loadRequest:request];
    [self.view addSubview:webView];
}

问题来了
加载网络链接的时候正常加载；
但是、
加载本地pdf的时候为空白页、
控制台log输出：

2020-05-22 15:19:12.172698+0800 appDemo[23683:1471101] WF: === Starting WebFilter logging for process 学谷智能
2020-05-22 15:19:12.172771+0800 appDemo[23683:1471101] WF: _userSettingsForUser mobile: {
    filterBlacklist =     (
    );
    filterWhitelist =     (
    );
    restrictWeb = 1;
    useContentFilter = 0;
    useContentFilterOverrides = 0;
    whitelistEnabled = 0;
}
2020-05-22 15:19:12.172812+0800 appDemo[23683:1471101] WF: _WebFilterIsActive returning: NO

然后很纠结、再然后就沙雕了

//既然是加载本地的，那就是用fileURLWithPath啊
NSURL *pdfUrl = [NSURL fileURLWithPath:path];

//谁让我用了
[NSURL URLWithString:];

GG