如何在iOS中调用Javascript方法?

时间:2015-06-02 06:13:35

标签: javascript html ios webview



<html>
<head>
<script type="text/javascript" src="js/jquery.js"></script>
<script type="text/javascript" src="js/quiz-1.js"></script>
<link rel="stylesheet" type="text/css" href="style.css" />
</head>
<body>
<p class="question">1. What is the answer to this question?</p>        

<ul class="answers">            
<input type="radio" name="q1" value="a" id="q1a"><label for="q1a">Answer 1</label><br/>          
<input type="radio" name="q1" value="b" id="q1b"><label for="q1b">Answer 2</label><br/>            
<input type="radio" name="q1" value="c" id="q1c"><label for="q1c">Answer 3</label><br/>            
<input type="radio" name="q1" value="d" id="q1d"><label for="q1d">Answer 4</label><br/>       
</ul>        


<p class="question">2. What is the answer to this question?</p>        

<ul class="answers">            
<input type="radio" name="q2" value="a" id="q2a"><label for="q2a">Answer 1</label><br/>           
<input type="radio" name="q2" value="b" id="q2b"><label for="q2b">Answer 2</label><br/>            
<input type="radio" name="q2" value="c" id="q2c"><label for="q2c">Answer 3</label><br/>           
<input type="radio" name="q2" value="d" id="q2d"><label for="q2d">Answer 4</label><br/>       
</ul>        

<p class="question">3. What is the answer to this question?</p>        

<ul class="answers">            
<input type="radio" name="q3" value="a" id="q3a"><label for="q3a">Answer 1</label><br/>            
<input type="radio" name="q3" value="b" id="q3b"><label for="q3b">Answer 2</label><br/>            
<input type="radio" name="q3" value="c" id="q3c"><label for="q3c">Answer 3</label><br/>           
<input type="radio" name="q3" value="d" id="q3d"><label for="q3d">Answer 4</label><br/>       
</ul>        

<p class="question">4. What is the answer to this question?</p>        

<ul class="answers">           
<input type="radio" name="q4" value="a" id="q4a"><label for="q4a">Answer 1</label><br/>            
<input type="radio" name="q4" value="b" id="q4b"><label for="q4b">Answer 2</label><br/>            
<input type="radio" name="q4" value="c" id="q4c"><label for="q4c">Answer 3</label><br/>            
<input type="radio" name="q4" value="d" id="q4d"><label for="q4d">Answer 4</label><br/>        
</ul>        

<p class="question">5. What is the answer to this question?</p>        

<ul class="answers">            
<input type="radio" name="q5" value="a" id="q5a"><label for="q5a">Answer 1</label><br/>            
<input type="radio" name="q5" value="b" id="q5b"><label for="q5b">Answer 2</label><br/>            
<input type="radio" name="q5" value="c" id="q5c"><label for="q5c">Answer 3</label><br/>           
<input type="radio" name="q5" value="d" id="q5d"><label for="q5d">Answer 4</label><br/>        
</ul>        

<p class="question">6. What is the answer to this question?</p>        

<ul class="answers">            
<input type="radio" name="q6" value="a" id="q6a"><label for="q6a">Answer 1</label><br/>            
<input type="radio" name="q6" value="b" id="q6b"><label for="q6b">Answer 2</label><br/>            
<input type="radio" name="q6" value="c" id="q6c"><label for="q6c">Answer 3</label><br/>            
<input type="radio" name="q6" value="d" id="q6d"><label for="q6d">Answer 4</label><br/>        
</ul>       

<p class="question">7. What is the answer to this question?</p>        

<ul class="answers">            
<input type="radio" name="q7" value="a" id="q7a"><label for="q7a">Answer 1</label><br/>            
<input type="radio" name="q7" value="b" id="q7b"><label for="q7b">Answer 2</label><br/>            
<input type="radio" name="q7" value="c" id="q7c"><label for="q7c">Answer 3</label><br/>            
<input type="radio" name="q7" value="d" id="q7d"><label for="q7d">Answer 4</label><br/>        
</ul>        

<p class="question">8. What is the answer to this question?</p>        

<ul class="answers">            
<input type="radio" name="q8" value="a" id="q8a"><label for="q8a">Answer 1</label><br/>            
<input type="radio" name="q8" value="b" id="q8b"><label for="q8b">Answer 2</label><br/>            
<input type="radio" name="q8" value="c" id="q8c"><label for="q8c">Answer 3</label><br/>            
<input type="radio" name="q8" value="d" id="q8d"><label for="q8d">Answer 4</label><br/>       
</ul>        

<p class="question">9. What is the answer to this question?</p>        

<ul class="answers">            
<input type="radio" name="q9" value="a" id="q9a"><label for="q9a">Answer 1</label><br/>            
<input type="radio" name="q9" value="b" id="q9b"><label for="q9b">Answer 2</label><br/>            
<input type="radio" name="q9" value="c" id="q9c"><label for="q9c">Answer 3</label><br/>            
<input type="radio" name="q9" value="d" id="q9d"><label for="q9d">Answer 4</label><br/>        
</ul>        

<p class="question">10. What is the answer to this question?</p>        

<ul class="answers">           
<input type="radio" name="q10" value="a" id="q10a"><label for="q10a">Answer 1</label><br/>            
<input type="radio" name="q10" value="b" id="q10b"><label for="q10b">Answer 2</label><br/>            
<input type="radio" name="q10" value="c" id="q10c"><label for="q10c">Answer 3</label><br/>            
<input type="radio" name="q10" value="d" id="q10d"><label for="q10d">Answer 4</label><br/>        
</ul>        

<br/>
<div id="results">            
Show me the answers!       
</div>                

<div id="category1">            
<p>              
<strong>Question 1:</strong> The correct answer is the <strong>Answer 1</strong>.</p>        
</div>        

<div id="category2">            
<p>              
<strong>Question 2:</strong> The correct answer is <strong>Answer 2</strong>.</p>        
</div>        

<div id="category3">            
<p>                
<strong>Question 3:</strong> The correct answer is <strong>Answer 3</strong>.</p>        
</div>        

<div id="category4">            
<p>               
<strong>Question 4:</strong> The correct answer is <strong>Answer 4</strong>.</p>        
</div>        

<div id="category5">            
<p>                
<strong>Question 5:</strong> The correct answer is <strong>Answer 1</strong>.</p>        
</div>        

<div id="category6">            
<p>                
<strong>Question 6:</strong> The correct answer is <strong>Answer 2</strong>.</p>        
</div>        

<div id="category7">            
<p>                
<strong>Question 7:</strong> The correct answer is <strong>Answer 3</strong>.</p>        
</div>        

<div id="category8">            
<p>               
<strong>Question 8:</strong> The correct answer is <strong>Answer 4</strong>.</p>        
</div>        

<div id="category9">           
<p>               
<strong>Question 9:</strong> The correct answer is <strong>Answer 1</strong>.</p>        
</div>        

<div id="category10">            
<p>                
<strong>Question 10:</strong> The correct answer is <strong>Answer 2</strong>.</p>        
</div>        

<div id="category11">            
<p>                
You answered them all right!</p>        
</div>
</body>
</html>
&#13;
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我的iOS编码面临一个大问题。我的要求是我有一个 HTML 文件。该文件包含一些多项选择Q&amp; A.我在UIWebView中加载该html文件。当我单击该答案按钮时,我必须检索在webView上单击了哪个按钮。

我必须从html文件中检索该方法。

怎么可能?

这不是一个重复的问题,我已经用Google搜索了这个,无论我得到什么,它都不能满足我的要求。

我的代码如下:

- (void)viewDidLoad {
    [super viewDidLoad];

    NSString *path;
    NSBundle *thisBundle = [NSBundle mainBundle];
    path = [thisBundle pathForResource:@"Untitled" ofType:@"html"];
    NSURL *instructionsURL = [NSURL fileURLWithPath:path];
   [_webview loadRequest:[NSURLRequest requestWithURL:instructionsURL]];
  }
  - (void)webViewDidFinishLoad:(UIWebView*)theWebView
  {
    NSString* returnValue =[theWebView stringByEvaluatingJavaScriptFromString:@"myFunction()"];
    NSLog(@"returnValue = %@ ",returnValue);
  }
  - (void)webView:(UIWebView *)webView didFailLoadWithError:(NSError *)error
  {
     NSLog(@" didFailLoadWithError");
  }

enter image description here

但我的输出是: Sample_JS [2218:44719] returnValue =

请帮帮我....

4 个答案:

答案 0 :(得分:4)

在您的代码中,这是事情发生的顺序:

  1. 您在viewDidload
  2. 中加载了请求
  3. 您的webview已完成加载。因此您可以选择该值。但此时此刻。您还没有选择任何内容。
  4. 当您选择某个项目时,您没有做任何事情告诉iOS您选择了一个
  5. 所以,我建议使用WKWebview,最好使用JS代码。

    1. 在您的js代码中,添加一个提交按钮。 然后在按钮动作功能

      function submit () {
          var message = //here get all your selected items
          window.webkit.messageHandlers.observe.postMessage(message);
       }
      
    2. 在ViewController中,创建WKUserContentController来处理通知

      WKWebViewConfiguration *configuration = [[WKWebViewConfiguration alloc]init];
      WKUserContentController *controller = [[WKUserContentController alloc]
                                         init];
      [controller addScriptMessageHandler:self name:@"observe"];
       configuration.userContentController = controller;
      _webView = [[WKWebView alloc] initWithFrame:self.view.frame
                                configuration:configuration];
      
    3. 在委托方法中,处理js事件

      -(void)userContentController:(WKUserContentController *)userContentController
        didReceiveScriptMessage:(WKScriptMessage *)message {
      //message.body
      }
      
    4. 更新整个项目

      #import <WebKit/WebKit.h>
      @interface ViewController ()<WKScriptMessageHandler>
      
      @property (strong, nonatomic) WKWebView  * webview;
      
      @end
      
      @implementation ViewController
      
      - (void)viewDidLoad {
          NSString *path;
          NSBundle *thisBundle = [NSBundle mainBundle];
          path = [thisBundle pathForResource:@"Untitled" ofType:@"html"];
          NSURL *instructionsURL = [NSURL fileURLWithPath:path];
      
          WKWebViewConfiguration *configuration = [[WKWebViewConfiguration alloc]init];
          WKUserContentController *controller = [[WKUserContentController alloc]
                                             init];
          [controller addScriptMessageHandler:self name:@"observe"];
          configuration.userContentController = controller;
          _webview = [[WKWebView alloc] initWithFrame:self.view.frame
                                    configuration:configuration];
          [_webview loadRequest:[NSURLRequest requestWithURL:instructionsURL]];
          [self.view addSubview:self.webview];
      }
      
      -(void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message{
          NSLog(@"%@",message.body);
      }
      

      和htmlfile

      <html>
      <head>
      <script type="text/javascript">
      function getFirstSelect(){
          var rates = document.getElementsByName('q1');
          var rate_value;
          for(var i = 0; i < rates.length; i++){
              if(rates[i].checked){
                  rate_value = rates[i].value;
                  break;
              }
          }
          window.webkit.messageHandlers.observe.postMessage(rate_value);
      }
      </script>
      
      <link rel="stylesheet" type="text/css" href="style.css" />
      </head>
      <body>
      <p class="question">1. What is the answer to this question?</p>
      
      <ul class="answers">
      <input type="radio" name="q1" value="a" id="q1a"><label for="q1a">Answer 1</label><br/>
      <input type="radio" name="q1" value="b" id="q1b"><label for="q1b">Answer 2</label><br/>
      <input type="radio" name="q1" value="c" id="q1c"><label for="q1c">Answer 3</label><br/>
      <input type="radio" name="q1" value="d" id="q1d"><label for="q1d">Answer 4</label><br/>
      </ul>
      
      <div id="Submit">
           <button onclick="getFirstSelect()">Submit</button>
      </div>
      
      </body>
      </html>
      

      点击提交时 enter image description here

      这是测试项目,我相信你可以自己找出休息

答案 1 :(得分:1)

最后我能够解决这个大问题..

首先为WebView设置委托方法。

 - (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType
{
 if ([[[request URL] absoluteString] hasPrefix:@"ios:"])
 {
    // Call the given selector
    [self performSelector:@selector(webToNativeCall)];
    return NO;
 }
 return YES;
}

- (void)webToNativeCall
{
 NSString *returnvalue =  [self.webview stringByEvaluatingJavaScriptFromString:@"returnVal()"];
 NSLog(@"returnvalue == %@",returnvalue);
}

在javascript文件中:

function getData ()
{
   window.location  = 'ios:webToNativeCall';
}
function returnVal(){
  return values;
}

答案 2 :(得分:0)

请检查以下代码,我已在我的系统中测试过。

- (void)viewDidLoad
{
    [super viewDidLoad];

    NSString *htmlFile = [[NSBundle mainBundle] pathForResource:@"File" ofType:@"html"];
    NSString* htmlString = [NSString stringWithContentsOfFile:htmlFile encoding:NSUTF8StringEncoding error:nil];
    [self.webView loadHTMLString:htmlString baseURL:nil];

}

单击单选按钮后检查html结果的按钮操作方法 -

- (IBAction)action:(id)sender {

    NSString* javaScriptString = @"document.querySelector('input[name=\"sex\"]:checked').value;";
    NSLog(@"%@",  [self.webView stringByEvaluatingJavaScriptFromString: javaScriptString]);
}

Html文件 -

<!DOCTYPE html>
<html>
    <body>

        <form action="">
            <input type="radio" name="sex" value="male">Male<br>
            <input type="radio" name="sex" value="female">Female
        </form>

    </body>
</html>

答案 3 :(得分:0)

你必须在JavaScript中创建一个存储answer值的全局变量。 你的函数myFunction()在webview加载后调用,当时选择用户时没有调用函数。所以你必须在一段时间内快速调用该函数并检查它的值是什么