blocks|key|1154957|text|正如我在对原始问题的评论中所指出的，JavaScript注入方法是可行的。基本上，您需要做的是向DOM+onsubmit事件添加一些JavaScript代码，让它解析表单的字段，并将结果返回给Java注册的函数。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1154958|代码示例：|1154959|public+class+MyBrowser+extends+Activity+{
++++private+final+String+jsInjectCode+=+
++++++++"function+parseForm(event)+{"+%2B
++++++++"++++var+form+=+this;"+%2B
++++++++"++++//+make+sure+form+points+to+the+surrounding+form+object+if+a+custom+button+was+used"+%2B
++++++++"++++if+(this.tagName.toLowerCase()+!=+'form')"+%2B
++++++++"++++++++form+=+this.form;"+%2B++++
++++++++"++++var+data+=+'';"+%2B
++++++++"++++if+(!form.method)++form.method+=+'get';"+%2B
++++++++"++++data+%2B=+'method='+%2B+form.method;"+%2B
++++++++"++++data+%2B=+'&action='+%2B+form.action;"+%2B++++++++
++++++++"++++var+inputs+=+document.forms[0].getElementsByTagName('input');"+%2B
++++++++"++++for+(var+i+=+0;+i+<+inputs.length;+i%2B%2B)+{"+%2B
++++++++"+++++++++var+field+=+inputs[i];"+%2B
++++++++"+++++++++if+(field.type+!=+'submit'+&&+field.type+!=+'reset'+&&+field.type+!=+'button')"+%2B
++++++++"+++++++++++++data+%2B=+'&'+%2B+field.name+%2B+'='+%2B+field.value;"+%2B
++++++++"++++}"+%2B
++++++++"++++HTMLOUT.processFormData(data);"+%2B
++++++++"}"+%2B
++++++++""+%2B
++++++++"for+(var+form_idx+=+0;+form_idx+<+document.forms.length;+%2B%2Bform_idx)"+%2B
++++++++"++++document.forms[form_idx].addEventListener('submit',+parseForm,+false);"+%2B++++
++++++++"var+inputs+=+document.getElementsByTagName('input');"+%2B
++++++++"for+(var+i+=+0;+i+<+inputs.length;+i%2B%2B)+{"+%2B
++++++++"++++if+(inputs[i].getAttribute('type')+==+'button')"+%2B
++++++++"++++++++inputs[i].addEventListener('click',+parseForm,+false);"+%2B
++++++++"}"+%2B
++++++++"";

++++class+JavaScriptInterface+{
++++++++@JavascriptInterface
++++++++public+void+processFormData(String+formData)+{
++++++++++++//added+annotation+for+API+>+17+to+make+it+work
++++++++++++<do+whatever+you+need+to+do+with+the+form+data>
++++++++}
++++}

++++onCreate(Bundle+savedInstanceState)+{
++++++++super.onCreate(savedInstanceState);
++++++++setContentView(R.layout.browser);
++++++++WebView+browser+=+(WebView)findViewById(R.id.browser_window);
++++++++browser.getSettings().setJavaScriptEnabled(true);
++++++++browser.addJavascriptInterface(new+JavaScriptInterface(),+"HTMLOUT");
++++++++browser.setWebViewClient(new+WebViewClient()+{
++++++++@Override
++++++++public+boolean+shouldOverrideUrlLoading(WebView+view,+String+url)+{
++++++++++++view.loadUrl(url);
++++++++++++return+true;
++++++++}

++++++++@Override
++++++++public+void+onPageFinished(WebView+view,+String+url)+{
++++++++++++view.loadUrl("javascript:(function()+{+"+%2B+
++++++++++++++++++++++MyBrowser.jsInjectCode+%2B+"})()");
++++++++}
}|code-block|syntax|javascript|1154960|非正式地，它所做的是在页面完成加载时注入定制JavaScript代码(作为onsubmit处理程序)。在提交表单时，Javascript将解析表单数据，并通过JavaScriptInterface对象将其传递回Java+land。|offset|length|style|CODE|1154961|为了解析表单字段，Javascript代码添加了表单onsubmit和按钮onclick处理程序。前者可以通过常规的提交按钮处理规范的表单提交，而后者处理自定义的提交按钮，即在调用form.submit()之前执行一些额外的Javascript魔术的按钮。|1154962|请注意，Javascript代码可能并不完美:可能还有其他方法可以提交表单，而我插入的代码可能无法捕获这些表单。然而，我相信注入的代码可以更新以处理这种可能性。|1154963|entityMap^0|0|0|0|11|8|27|J|0|Q|8|11|7|2I|D|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|W|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|X|8|@$K|Y|L|Z|M|N]|$K|10|L|11|M|N]]|9|@]|A|$]]|$1|O|3|P|5|6|7|12|8|@$K|13|L|14|M|N]|$K|15|L|16|M|N]|$K|17|L|18|M|N]]|9|@]|A|$]]|$1|Q|3|R|5|6|7|19|8|@]|9|@]|A|$]]|$1|S|3|-4|5|6|7|1A|8|@]|9|@]|A|$]]]|T|$]]

As indicated in my own comment to the original question, the JavaScript injection approach works. Basically, what you need to do is add some piece of JavaScript code to the DOM onsubmit event, have it parse the form's fields, and return the result back to a Java-registered function.

Code example:

<pre><code>public class MyBrowser extends Activity {
 private final String jsInjectCode = 
 "function parseForm(event) {" +
 " var form = this;" +
 " // make sure form points to the surrounding form object if a custom button was used" +
 " if (this.tagName.toLowerCase() != 'form')" +
 " form = this.form;" + 
 " var data = '';" +
 " if (!form.method) form.method = 'get';" +
 " data += 'method=' + form.method;" +
 " data += '&amp;action=' + form.action;" + 
 " var inputs = document.forms[0].getElementsByTagName('input');" +
 " for (var i = 0; i &lt; inputs.length; i++) {" +
 " var field = inputs[i];" +
 " if (field.type != 'submit' &amp;&amp; field.type != 'reset' &amp;&amp; field.type != 'button')" +
 " data += '&amp;' + field.name + '=' + field.value;" +
 " }" +
 " HTMLOUT.processFormData(data);" +
 "}" +
 "" +
 "for (var form_idx = 0; form_idx &lt; document.forms.length; ++form_idx)" +
 " document.forms[form_idx].addEventListener('submit', parseForm, false);" + 
 "var inputs = document.getElementsByTagName('input');" +
 "for (var i = 0; i &lt; inputs.length; i++) {" +
 " if (inputs[i].getAttribute('type') == 'button')" +
 " inputs[i].addEventListener('click', parseForm, false);" +
 "}" +
 "";

 class JavaScriptInterface {
 @JavascriptInterface
 public void processFormData(String formData) {
 //added annotation for API &gt; 17 to make it work
 &lt;do whatever you need to do with the form data&gt;
 }
 }

 onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.browser);
 WebView browser = (WebView)findViewById(R.id.browser_window);
 browser.getSettings().setJavaScriptEnabled(true);
 browser.addJavascriptInterface(new JavaScriptInterface(), "HTMLOUT");
 browser.setWebViewClient(new WebViewClient() {
 @Override
 public boolean shouldOverrideUrlLoading(WebView view, String url) {
 view.loadUrl(url);
 return true;
 }

 @Override
 public void onPageFinished(WebView view, String url) {
 view.loadUrl("javascript:(function() { " + 
 MyBrowser.jsInjectCode + "})()");
 }
}
</code></pre>

Informally, what this does is inject the custom JavaScript code (as a <code>onsubmit</code> handler) whenever a page finishes loading. On submission of a form, Javascript will parse the form data and pass it back to Java land through the <code>JavaScriptInterface</code> object.

In order to parse form fields, the Javascript code adds form <code>onsubmit</code> and button <code>onclick</code> handlers. The former can handle canonical form submissions through a regular submit button while the latter deals with custom submit buttons, i.e., buttons that do some additional Javascript magic before calling <code>form.submit()</code>.

Please be aware that the Javascript code may not be perfect: There might be other methods to submit a form that my injected code may not be able to catch. However, I'm convinced that the injected code can be updated to deal with such possibilities.

blocks|key|940751|text|提供的答案给出了错误，所以我决定做一个更简单的实现，它也具有良好结构的JavaScript+(意味着JS在一个文件中)：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|940752|在assets文件夹中，创建一个名为inject.js的文件，其中包含以下代码：|940753|document.getElementsByTagName('form')[0].onsubmit+=+function+()+{
++++var+objPWD,+objAccount,+objSave;
++++var+str+=+'';
++++var+inputs+=+document.getElementsByTagName('input');
++++for+(var+i+=+0;+i+<+inputs.length;+i%2B%2B)+{
++++++++if+(inputs[i].name.toLowerCase()+===+'username')+{
++++++++++++objAccount+=+inputs[i];
++++++++}+else+if+(inputs[i].name.toLowerCase()+===+'password')+{
++++++++++++objPWD+=+inputs[i];
++++++++}+else+if+(inputs[i].name.toLowerCase()+===+'rememberlogin')+{
++++++++++++objSave+=+inputs[i];
++++++++}
++++}
++++if(objAccount+!=+null)+{
++++++++str+%2B=+objAccount.value;
++++}
++++if(objPWD+!=+null)+{
++++++++str+%2B=+'+,+'+%2B+objPWD.value;
++++}
++++if(objSave+!=+null)+{
++++++++str+%2B=+'+,+'+%2B+objSave.value;
++++}
++++window.AndroidInterface.processHTML(str);
++++return+true;
};|code-block|syntax|javascript|940754|这是我们将用于注入的javascript代码，您可以根据自己的需要替换掉if语句，并使用类型，或者使用下面这行代码：window.AndroidInterface.processHTML(str);|offset|length|style|CODE|940755|那么你的活动/片段应该是这样的：|940756|public+class+MainActivity+extends+ActionBarActivity+{
++++class+JavaScriptInterface+{
++++++++@JavascriptInterface
++++++++public+void+processHTML(String+formData)+{
++++++++++++Log.d("AWESOME_TAG",+"form+data:+"+%2B+formData);
++++++++}
++++}

++++@Override
++++protected+void+onCreate(Bundle+savedInstanceState)+{
++++++++super.onCreate(savedInstanceState);
++++++++WebView+webView+=+new+WebView(this);
++++++++this.setContentView(webView);

++++++++//+enable+javascript
++++++++WebSettings+webSettings+=+webView.getSettings();
++++++++webSettings.setJavaScriptEnabled(true);
++++++++webView.addJavascriptInterface(new+JavaScriptInterface(),+"AndroidInterface");

++++++++//+catch+events
++++++++webView.setWebViewClient(new+WebViewClient(){
++++++++++++@Override
++++++++++++public+void+onPageFinished(WebView+view,+String+url)+{
++++++++++++++++try+{
++++++++++++++++++++view.loadUrl("javascript:"+%2B+buildInjection());
++++++++++++++++}+catch+(IOException+e)+{
++++++++++++++++++++e.printStackTrace();
++++++++++++++++}
++++++++++++}
++++++++});

++++++++webView.loadUrl("http://someurl.com");
++++}

++++private+String+buildInjection()+throws+IOException+{
++++++++StringBuilder+buf+=+new+StringBuilder();
++++++++InputStream+inject+=+getAssets().open("inject.js");//+file+from+assets
++++++++BufferedReader+in+=+new+BufferedReader(new+InputStreamReader(inject,+"UTF-8"));
++++++++String+str;
++++++++while+((str+=+in.readLine())+!=+null)+{
++++++++++++buf.append(str);
++++++++}
++++++++in.close();

++++++++return+buf.toString();
++++}|940757|entityMap^0|0|0|0|1M|15|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|W|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|X|8|@$K|Y|L|Z|M|N]]|9|@]|A|$]]|$1|O|3|P|5|6|7|10|8|@]|9|@]|A|$]]|$1|Q|3|R|5|F|7|11|8|@]|9|@]|A|$G|H]]|$1|S|3|-4|5|6|7|12|8|@]|9|@]|A|$]]]|T|$]]

The provided answer gives error so I decided to make a simpler implementation which also featured well structured JavaScript (meaning JS is in a file):

In your assets folder create a file called inject.js with following code inside:

<pre><code>document.getElementsByTagName('form')[0].onsubmit = function () {
 var objPWD, objAccount, objSave;
 var str = '';
 var inputs = document.getElementsByTagName('input');
 for (var i = 0; i &lt; inputs.length; i++) {
 if (inputs[i].name.toLowerCase() === 'username') {
 objAccount = inputs[i];
 } else if (inputs[i].name.toLowerCase() === 'password') {
 objPWD = inputs[i];
 } else if (inputs[i].name.toLowerCase() === 'rememberlogin') {
 objSave = inputs[i];
 }
 }
 if(objAccount != null) {
 str += objAccount.value;
 }
 if(objPWD != null) {
 str += ' , ' + objPWD.value;
 }
 if(objSave != null) {
 str += ' , ' + objSave.value;
 }
 window.AndroidInterface.processHTML(str);
 return true;
};
</code></pre>

This is the javascript code we'll use for injections, you can switch out the if statements as you see fit and use types instead or names.The callback to Android is this line: <code>window.AndroidInterface.processHTML(str);</code>

Then your Activity/fragment should look like this:

<pre><code>public class MainActivity extends ActionBarActivity {
 class JavaScriptInterface {
 @JavascriptInterface
 public void processHTML(String formData) {
 Log.d("AWESOME_TAG", "form data: " + formData);
 }
 }

 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 WebView webView = new WebView(this);
 this.setContentView(webView);

 // enable javascript
 WebSettings webSettings = webView.getSettings();
 webSettings.setJavaScriptEnabled(true);
 webView.addJavascriptInterface(new JavaScriptInterface(), "AndroidInterface");

 // catch events
 webView.setWebViewClient(new WebViewClient(){
 @Override
 public void onPageFinished(WebView view, String url) {
 try {
 view.loadUrl("javascript:" + buildInjection());
 } catch (IOException e) {
 e.printStackTrace();
 }
 }
 });

 webView.loadUrl("http://someurl.com");
 }

 private String buildInjection() throws IOException {
 StringBuilder buf = new StringBuilder();
 InputStream inject = getAssets().open("inject.js");// file from assets
 BufferedReader in = new BufferedReader(new InputStreamReader(inject, "UTF-8"));
 String str;
 while ((str = in.readLine()) != null) {
 buf.append(str);
 }
 in.close();

 return buf.toString();
 }
</code></pre>

I've started to write an app which provides the user with an HTML form via a WebView. As the form is not under my control, the data filled in may be sent as either GET or POST request. My app is required to capture the transported form data, that is, get a hold on what was entered into the form fields.

Using an adequate callback from WebViewClient such as <code>onPageLoaded()</code>, it is easy to capture form data from a GET request. However, I cannot find any appropriate method to allow the same for POSTed data, i.e., be able to access the HTTP POST message body containing the form data. Am I missing a relevant callback here or is there simply no way to accomplish the specified goal with the given API (even the latest level 8)?

Assuming it wasn't possible, I considered overriding and extending parts of android.webkit in order to introduce a new callback hook that is passed the POST body somehow. That way, my app could be shipped with a customized browser/WebViewClient that fulfills the desired feature. However, I couldn't find any good spot to start with in the code and would be glad for any hints in this regards (in case the approach looks promising at all).

Thanks in advance!

is it possible to access HTML form data POSTed through a WebView?

Java

我已经开始编写一个应用程序，通过一个WebView为用户提供一个超文本标记语言表单。由于表单不在我的控制之下，填写的数据可能会以GET或POST请求的形式发送。我的应用程序需要捕获传输的表单数据，即获取输入到表单域中的内容。使用来自WebViewClient的适当回调(如onPageLoaded() )，可以轻松地从G...

问可以通过WebView访问HTML form data POSTed吗？
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