@interface BaiduViewController () <WKNavigationDelegate, WKUIDelegate>

@property (strong, nonatomic) WKWebView *webView;

@end

@implementation BaiduViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.

    _webView = [[WKWebView alloc] initWithFrame:self.view.bounds];
    _webView.UIDelegate = self;
    _webView.navigationDelegate = self;
    [self.view addSubview:_webView];

    [_webView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"http://www.baidu.com"]]];
}

#pragma mark - WKNavigationDelegate

/**
 *  页面开始加载时调用
 *
 *  @param webView    实现该代理的webview
 *  @param navigation 当前navigation
 */
- (void)webView:(WKWebView *)webView didStartProvisionalNavigation:(WKNavigation *)navigation {

    NSLog(@"%s", __FUNCTION__);
}

/**
 *  当内容开始返回时调用
 *
 *  @param webView    实现该代理的webview
 *  @param navigation 当前navigation
 */
- (void)webView:(WKWebView *)webView didCommitNavigation:(WKNavigation *)navigation {

    NSLog(@"%s", __FUNCTION__);
}

/**
 *  页面加载完成之后调用
 *
 *  @param webView    实现该代理的webview
 *  @param navigation 当前navigation
 */
- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation {

    NSLog(@"%s", __FUNCTION__);
}

/**
 *  加载失败时调用
 *
 *  @param webView    实现该代理的webview
 *  @param navigation 当前navigation
 *  @param error      错误
 */
- (void)webView:(WKWebView *)webView didFailProvisionalNavigation:(WKNavigation *)navigation withError:(NSError *)error {

    NSLog(@"%s", __FUNCTION__);
}

/**
 *  接收到服务器跳转请求之后调用
 *
 *  @param webView      实现该代理的webview
 *  @param navigation   当前navigation
 */
- (void)webView:(WKWebView *)webView didReceiveServerRedirectForProvisionalNavigation:(WKNavigation *)navigation {

    NSLog(@"%s", __FUNCTION__);
}

/**
 *  在收到响应后，决定是否跳转
 *
 *  @param webView            实现该代理的webview
 *  @param navigationResponse 当前navigation
 *  @param decisionHandler    是否跳转block
 */
- (void)webView:(WKWebView *)webView decidePolicyForNavigationResponse:(WKNavigationResponse *)navigationResponse decisionHandler:(void (^)(WKNavigationResponsePolicy))decisionHandler {

    // 如果响应的地址是百度，则允许跳转
    if ([navigationResponse.response.URL.host.lowercaseString isEqual:@"www.baidu.com"]) {

        // 允许跳转
        decisionHandler(WKNavigationResponsePolicyAllow);
        return;
    }
    // 不允许跳转
    decisionHandler(WKNavigationResponsePolicyCancel);
}

/**
 *  在发送请求之前，决定是否跳转
 *
 *  @param webView          实现该代理的webview
 *  @param navigationAction 当前navigation
 *  @param decisionHandler  是否调转block
 */
- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler {

    // 如果请求的是百度地址，则延迟5s以后跳转
    if ([navigationAction.request.URL.host.lowercaseString isEqual:@"www.baidu.com"]) {

//        // 延迟5s之后跳转
//        dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(5 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
//            
//            // 允许跳转
//            decisionHandler(WKNavigationActionPolicyAllow);
//        });

        // 允许跳转
        decisionHandler(WKNavigationActionPolicyAllow);
        return;
    }
    // 不允许跳转
    decisionHandler(WKNavigationActionPolicyCancel);
}

@end