how to get html content from a webview

Question

Which is the simplest method to get html code from a webview  I have tried several methods from stackoverflow and google  but can t find an exact method  Please mention an exact way   public class htmldecoder extends Activity implements OnClickListener TextWatcher   TextView txturl  Button btgo  WebView wvbrowser  TextView txtcode  ImageButton btcode  LinearLayout llayout  int flagbtcode  public void onCreate Bundle savedInstanceState                super onCreate savedInstanceState                   setContentView R layout htmldecoder        txturl  TextView findViewById R id txturl        btgo  Button findViewById R id btgo       btgo setOnClickListener this        wvbrowser  WebView findViewById R id wvbrowser       wvbrowser setWebViewClient new HelloWebViewClient         wvbrowser getSettings   setJavaScriptEnabled true       wvbrowser getSettings   setPluginsEnabled true       wvbrowser getSettings   setJavaScriptCanOpenWindowsAutomatically true       wvbrowser addJavascriptInterface new MyJavaScriptInterface    HTMLOUT          wvbrowser loadUrl  http   www google com        wvbrowser loadUrl  javascript window HTMLOUT showHTML   lt html gt   document getElementsByTagName  html   0  innerHTML   lt  html gt              txtcode  TextView findViewById R id txtcode       txtcode addTextChangedListener this        btcode  ImageButton findViewById R id btcode       btcode setOnClickListener this           public void onClick View v        if btgo  v                String url txturl getText   toString            if  txturl getText   toString   contains  http                             url  http     url                    wvbrowser loadUrl url             wvbrowser loadData   lt html gt  lt head gt  lt  head gt  lt body gt  lt div style  width 100px height 100px border 1px red solid   gt  lt  div gt  lt  body gt  lt  html gt    text html   utf-8              else if btcode  v                ViewGroup LayoutParams params1 wvbrowser getLayoutParams            ViewGroup LayoutParams params2 txtcode getLayoutParams            if flagbtcode  1                        params1 height 200              params2 height 220              flagbtcode 0                txtcode setText wvbrowser getContentDescription                       else                       params1 height 420              params2 height 0              flagbtcode 1                    wvbrowser setLayoutParams params1           txtcode setLayoutParams params2             public class HelloWebViewClient extends WebViewClient        Override     public boolean shouldOverrideUrlLoading WebView view  String url             view loadUrl url           return true               Override     public void onPageFinished WebView view  String url                   This call inject JavaScript into the page which just finished loading           wvbrowser loadUrl  javascript window HTMLOUT processHTML   lt head gt   document getElementsByTagName  html   0  innerHTML   lt  head gt                   class MyJavaScriptInterface        SuppressWarnings  unused       public void showHTML String html                 txtcode setText html            public void afterTextChanged Editable s           TODO Auto-generated method stub     public void beforeTextChanged CharSequence s  int start  int count          int after           TODO Auto-generated method stub     public void onTextChanged CharSequence s  int start  int before  int count        wvbrowser loadData   lt html gt  lt div  txtcode getText   toString     gt  lt  div gt  lt  html gt    text html   utf-8

User · Answer

One touch point I found that needs to be put in place is "hidden" away in the Proguard configuration. While the HTML reader invokes through the javascript interface just fine when debugging the app, this works no longer as soon as the app was run through Proguard, unless the HTML reader function is declared in the Proguard config file, like so:

-keepclassmembers class <your.fully.qualified.HTML.reader.classname.here> {
    public *; 
}

Tested and confirmed on Android 2.3.6, 4.1.1 and 4.2.1.

User · Answer

Actually this question has many answers  Here are 2 of them       This first is almost the same as yours  I guess we got it from the same tutorial      public class TestActivity extends Activity         Override     protected void onCreate Bundle savedInstanceState            super onCreate savedInstanceState           setContentView R layout webview           final WebView webview    WebView  findViewById R id browser           webview getSettings   setJavaScriptEnabled true           webview addJavascriptInterface new MyJavaScriptInterface this    HtmlViewer             webview setWebViewClient new WebViewClient                  Override             public void onPageFinished WebView view  String url                    webview loadUrl  javascript window HtmlViewer showHTML                                lt html gt   document getElementsByTagName  html   0  innerHTML   lt  html gt                                           webview loadUrl  http   android-in-action com index php post                      Common-errors-and-bugs-and-how-to-solve-avoid-them               class MyJavaScriptInterface            private Context ctx           MyJavaScriptInterface Context ctx                this ctx   ctx                     public void showHTML String html                new AlertDialog Builder ctx  setTitle  HTML   setMessage html                       setPositiveButton android R string ok  null  setCancelable false  create   show                         This way your grab the html through javascript  Not the prettiest way but when you have your javascript interface  you can add other methods to tinker it      An other way is using an HttpClient like there    The option you choose also depends  I think  on what you intend to do with the retrieved html

User · Answer

I would suggest instead of trying to extract the HTML from the WebView  you extract the HTML from the URL  By this  I mean using a third party library such as JSoup to traverse the HTML for you  The following code will get the HTML from a specific URL for you  public static String getHtml String url  throws ClientProtocolException  IOException           HttpClient httpClient   new DefaultHttpClient            HttpContext localContext   new BasicHttpContext            HttpGet httpGet   new HttpGet url           HttpResponse response   httpClient execute httpGet  localContext           String result                BufferedReader reader   new BufferedReader              new InputStreamReader                  response getEntity   getContent                                     String line   null          while   line   reader readLine       null               result    line     n                     return result

User · Answer

Its Simple to implement Just need javasript methods in your html to get value of html content  As Above your code some changes to be need     public class htmldecoder extends Activity implements OnClickListener TextWatcher           Button btsubmit     this button in your xml file     WebView wvbrowser      public void onCreate Bundle savedInstanceState                        super onCreate savedInstanceState                       setContentView R layout htmldecoder              btsubmit  Button findViewById R id btsubmit           btsubmit setOnClickListener this            wvbrowser  WebView findViewById R id wvbrowser           wvbrowser setWebViewClient new HelloWebViewClient             wvbrowser getSettings   setJavaScriptEnabled true           wvbrowser getSettings   setPluginsEnabled true           wvbrowser getSettings   setJavaScriptCanOpenWindowsAutomatically true           MyJavaScriptInterface myinterface new MyJavaScriptInterface            wvbrowser addJavascriptInterface myinterface  interface            webView loadUrl  file    android asset simple html       use one html file for   testing put your html file in assets  Make sure that you done JavaScript methods to get   values for html content in html file            public void onClick View v        if btsubmit  v                 webView loadUrl  javascript showalert        call javascript method              wvbr          final class MyJavaScriptInterface              MyJavaScriptInterface                         public void sendValueFromHtml String value               System out println  Here is the value from html    value                         Your Javascript in html    lt script type  text javascript  gt         lt   CDATA      var n1      function callme        n1 document getElementById  FacadeAL   value            function showalert         window interface sendValueFromHtml n1     this method calling the method of interface which   you attached to html file in android      amp  we called this showalert javasript method on   submmit buttton click of android                  gt       lt  script gt     amp  Make sure you calling callme like below in html   lt input name  FacadeAL  id  FacadeAL  type  text  size  5   onblur  callme     gt  Hope this will help you

User · Answer

Android WebView is just another render engine that render HTML contents downloaded from a HTTP server  much like Chrome or FireFox  I don t know the reason why you need get the rendered page  or screenshot  from WebView  For most of situation  this is not necessary  You can always get the raw HTML content from HTTP server directly   There are already answers posted talking about getting the raw stream using HttpUrlConnection or HttpClient  Alternatively  there is a very handy library when dealing with HTML content parse process on Android  JSoup  it provide very simple API to get HTML contents form HTTP server  and provide an abstract representation of HTML document to help us manage HTML parsing not only in a more OO style but also much easily      Single line of statement to get HTML document from HTTP server  Document doc   Jsoup connect  http   en wikipedia org    get      It is handy when  for example  you want to download HTML document first then add some custom css or javascript to it before passing it to WebView for rendering  Much more on their official web site  worth to check it out

User · Answer

try using HttpClient as Sephy said   public String getHtml String url        HttpClient vClient   new DefaultHttpClient        HttpGet vGet   new HttpGet url       String response                try           ResponseHandler lt String gt  vHandler   new BasicResponseHandler            response   vClient execute vGet  vHandler         catch  Exception e            e printStackTrace              return response

User · Answer

For android 4 2  dont forget to add  JavascriptInterface to all javasscript functions

User · Answer

above given methods are for if you have an web url  but if you have an local html then you can have also html by this code   AssetManager mgr   mContext getAssets                 try   InputStream in   null                if condition   you have a local html saved in assets                                                           in   mgr open mFileName AssetManager ACCESS BUFFER                                                            else if condition   you have an url                                                           URL feedURL   new URL sURL                     in   feedURL openConnection   getInputStream                                     here you will get your html                  String sHTML   streamToString in                    in close                        display this html in the browser or web view                                catch  IOException e                    TODO Auto-generated catch block              e printStackTrace                           public static String streamToString InputStream in  throws IOException               if in    null                    return                                Writer writer   new StringWriter                char   buffer   new char 1024                try                   Reader reader   new BufferedReader new InputStreamReader in   UTF-8                      int n                  while   n   reader read buffer      -1                        writer write buffer  0  n                                    finally                               return writer toString

User · Answer

Android will not let you do this for security concerns   An evil developer could very easily steal user-entered login information   Instead  you have to catch the text being displayed in the webview before it is displayed   If you don t want to set up a response handler  as per the other answers   I found this fix with some googling   URL url   new URL  https   stackoverflow com questions 1381617    URLConnection con   url openConnection    Pattern p   Pattern compile  text html   s charset      s     s     Matcher m   p matcher con getContentType        If Content-Type doesn t match this pre-conception  choose default and     hope for the best     String charset   m matches     m group 1     ISO-8859-1   Reader r   new InputStreamReader con getInputStream    charset   StringBuilder buf   new StringBuilder    while  true      int ch   r read      if  ch  lt  0      break    buf append  char  ch     String str   buf toString      This is a lot of code  and you should be able to copy paster it  and at the end of it str will contain the same html drawn in the webview   This answer is from Simplest way to correctly load html from web page into a string in Java and it should work on Android as well   I have not tested this and did not write it myself  but it might help you out   Also  the URL this is pulling is hardcoded  so you ll have to change that

User · Answer

In KitKat and above  you could use evaluateJavascript method on webview  wvbrowser evaluateJavascript            function     return    lt html gt   document getElementsByTagName  html   0  innerHTML   lt  html gt                      new ValueCallback lt String gt                   Override             public void onReceiveValue String html                    Log d  HTML   html                       code here                         See this answer for more examples

User · Answer

I suggest to try out some Reflection approach  if you have time to spend on the debugger  sorry but I didn t have    Starting from the loadUrl   method of the android webkit WebView class   http   grepcode com file repository grepcode com java ext com google android android 2 2 r1 1 android webkit WebView java WebView loadUrl 28java lang String 2Cjava util Map 29  You should arrive on the android webkit BrowserFrame that call the nativeLoadUrl   native method   http   grepcode com file repository grepcode com java ext com google android android 2 2 r1 1 android webkit BrowserFrame java BrowserFrame nativeLoadUrl 28java lang String 2Cjava util Map 29  The implementation of the native method should be here   http   gitorious org 0xdroid external webkit blobs a538f34148bb04aa6ccfbb89dfd5fd784a4208b1 WebKit android jni WebCoreFrameBridge cpp  Wish you good luck

User · Answer

Why not get the html first then pass it to the web view   private String getHtml String url       HttpGet pageGet   new HttpGet url        ResponseHandler lt String gt  handler   new ResponseHandler lt String gt              public String handleResponse HttpResponse response  throws ClientProtocolException  IOException               HttpEntity entity   response getEntity                String html                if  entity    null                    html   EntityUtils toString entity                   return html                else                   return null                                      pageHTML   null      try           while  pageHTML  null               pageHTML   client execute pageGet  handler                   catch  ClientProtocolException e               TODO Auto-generated catch block         e printStackTrace          catch  IOException e               TODO Auto-generated catch block         e printStackTrace               return pageHTML      Override public void customizeWebView final ServiceCommunicableActivity activity  final WebView webview  final SearchResult mRom        mRom setFileSize getFileSize mRom getURLSuffix          webview getSettings   setJavaScriptEnabled true       WebViewClient anchorWebViewClient   new WebViewClient                   Override         public void onPageStarted WebView view  String url  Bitmap favicon                super onPageStarted view  url  favicon                  Do what you want to with the html             String html   getHTML url                if  html  null  amp  amp   url equals lastLoadedURL                    lastLoadedURL   url                  webview loadDataWithBaseURL url  html  null   utf-8   url                     This should roughly do what you want to do  It is adapted from Is it possible to get the HTML code from WebView and shout out to https   stackoverflow com users 325081 aymon-fournier for his answer

[android] how to get html content from a webview?

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