iOS中WkWebView与js交互

1、初始化wkwebview

- (WKWebView *)wkWebView{
    if (!_wkWebView) {
        //设置网页的配置文件
        WKWebViewConfiguration * Configuration = [[WKWebViewConfiguration alloc]init];
        //允许视频播放
        Configuration.allowsAirPlayForMediaPlayback = YES;
        // 允许在线播放
        Configuration.allowsInlineMediaPlayback = YES;
        // 允许可以与网页交互，选择视图
        Configuration.selectionGranularity = YES;
        // web内容处理池
        Configuration.processPool = [[WKProcessPool alloc] init];
        //自定义配置,一般用于 js调用oc方法(OC拦截URL中的数据做自定义操作)
        WKUserContentController * UserContentController = [[WKUserContentController alloc]init];
        // 添加消息处理，注意：self指代的对象需要遵守WKScriptMessageHandler协议，结束时需要移除
        [UserContentController addScriptMessageHandler:self name:@"WXPay"];
        // 是否支持记忆读取
Configuration.suppressesIncrementalRendering = YES;
        // 允许用户更改网页的设置
        Configuration.userContentController = UserContentController;
        _wkWebView = [[WKWebView alloc] initWithFrame:CGRectMake(0, 0, KScreenWidth, 200) configuration:Configuration];
        _wkWebView.backgroundColor = [UIColor colorWithRed:240.0/255 green:240.0/255 blue:240.0/255 alpha:1.0];
        // 设置代理
        _wkWebView.navigationDelegate = self;
        _wkWebView.UIDelegate = self;
        
        //kvo 添加进度监控
//        [_wkWebView addObserver:self forKeyPath:NSStringFromSelector(@selector(estimatedProgress)) options:0 context:WkwebBrowserContext];
        //开启手势触摸_wkWebView.allowsBackForwardNavigationGestures = YES;
    }
    return _wkWebView;
}

2、获取js返回的信息

- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message
{
    
}

3、原生调用js方法

[self.webView evaluateJavaScript:@"function('action')" completionHandler:nil];

4、拦截url（可在此方法中实现判断url执行相应的oc方法）：js会尝试加载某个URL，客户端在加载前拦截这个URL，通过解析这个URL识别它的内容，调用相应的原生方法，并阻止浏览器加载这个URL

- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler{
NSLog(@"%@",navigationAction.request.URL.absoluteString);
    NSURL *url = navigationAction.request.URL;
    NSString *urlStr = url.absoluteString;
    
    if ([urlStr isEqualToString:@"xxx"]) {
        // do something ;
        
        //不允许跳转
        decisionHandler(WKNavigationActionPolicyCancel);
        return;
    }
    //允许跳转decisionHandler(WKNavigationActionPolicyAllow);
}