Objective-C 代码与Javascript 代码相互调用实例

-(void)webViewLoad{
  
  NSURL * url = [[NSURL alloc]initWithString:@"http://www.baidu.com"];
  self.webView = [[UIWebView alloc]initWithFrame:self.view.bounds];
  NSURLRequest * request = [[NSURLRequest alloc]initWithURL:url];
  self.webView.delegate = self;
  [self.webView loadRequest:request];
  
  [self.view addSubview:self.webView];
  
}

//JS调用OC
-(BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType{
  NSString * str = request.URL.relativeString;
  if ([str isEqualToString:@"http://www.baidu.com/"]) {
    NSLog(@"来找度娘");
  }
  return YES;
}
//OC调用JS
-(void)webViewDidFinishLoad:(UIWebView *)webView{
  NSString * str = [self.webView stringByEvaluatingJavaScriptFromString:@"document.getElementById(""\"index-kw""\").value=""\"li""\""];
  NSLog(@"webViewDidFinishLoad=%@",str);
  
}

-(void)webViewBridge{
  self.webView = [[UIWebView alloc]initWithFrame:[UIScreen mainScreen].bounds];
  
  NSString * path = [[NSBundle mainBundle]pathForResource:@"ExampleApp.html" ofType:nil];
  NSURL * url = [[NSURL alloc]initFileURLWithPath:path];
  
  [self.webView loadRequest:[NSURLRequest requestWithURL:url]];
  self.webView.delegate = self;
  [self.view addSubview:self.webView];
  //设置能够桥接
  [WebViewJavascriptBridge enableLogging];
  //设置桥接
   self.bridge =  [WebViewJavascriptBridge bridgeForWebView:self.webView];
  //设置代理
  [self.bridge setWebViewDelegate:self];
  //JS调用OC（testObjcCallback是和html统一的方法名字）
  [self.bridge registerHandler:@"testObjcCallback" handler:^(id data, WVJBResponseCallback responseCallback) {
    NSLog(@"按钮点击了");
    self.view.backgroundColor= [UIColor blackColor];
    responseCallback(@"按钮点击了");
  }];
  
  
}


//OC调用JS

-(void)webViewDidFinishLoad:(UIWebView *)webView{
  NSLog(@"webViewDidFinishLoad");
  [self.bridge callHandler:@"registerHandler"];
}