Develop Reference

Webview does not load javascript to get content

I want to get all text in body tag of a url but it doesn't work. I have searched many but i could not find anything. I have also added android.permission.INTERNET also.
so what is the problem?
This is my code:
public class Activity_Main extends Activity {
#SuppressLint("JavascriptInterface")
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final WebView webView = (WebView) findViewById(R.id.webView);
webView.getSettings().setJavaScriptEnabled(true);
webView.getSettings().setDomStorageEnabled(true);
final TextView contentView = (TextView) findViewById(R.id.contentView);
class MyJavaScriptInterface
{
private TextView contentView;
public MyJavaScriptInterface(TextView aContentView)
{
contentView = aContentView;
}
#SuppressWarnings("unused")
public void processContent(String aContent)
{
final String content = aContent;
contentView.setText(content);
}
}
webView.getSettings().setJavaScriptEnabled(true);
webView.addJavascriptInterface(new MyJavaScriptInterface(contentView), "INTERFACE");
webView.setWebViewClient(new WebViewClient() {
#Override
public void onPageFinished(WebView view, String url)
{
webView.loadUrl("javascript:window.INTERFACE.processContent(document.getElementsByTagName('body')[0].innerText);");
}
});
webView.loadUrl("https://stackoverflow.com");
}
}

update #JavascriptInterface for your interface function and check
class MyJavaScriptInterface
{
private TextView contentView;
public MyJavaScriptInterface(TextView aContentView)
{
contentView = aContentView;
}
#JavascriptInterface
public void processContent(String aContent)
{
final String content = aContent;
contentView.setText(content);
}
}
and there is another way to do this is this for above KITKAT
webView.evaluateJavascript("alert('pass here some ...')", new ValueCallback<String>() {
#Override
public void onReceiveValue(String s) {
}
});
this is update solution for executing js in android
full code is here
final WebView webView = (WebView) findViewById(R.id.webView);
webView.getSettings().setJavaScriptEnabled(true);
webView.getSettings().setDomStorageEnabled(true);
final TextView contentView = (TextView) findViewById(R.id.contentView);
class MyJavaScriptInterface
{
private TextView contentView;
public MyJavaScriptInterface(TextView aContentView)
{
contentView = aContentView;
}
#JavascriptInterface
public void processContent(String aContent)
{
final String content = aContent;
contentView.setText(content);
}
}
webView.getSettings().setJavaScriptEnabled(true);
webView.addJavascriptInterface(new MyJavaScriptInterface(contentView), "INTERFACE");
webView.setWebViewClient(new WebViewClient() {
#Override
public void onPageFinished(WebView view, String url)
{
super.onPageFinished(view,url);
if (Build.VERSION.SDK_INT>=Build.VERSION_CODES.KITKAT) {
webView.evaluateJavascript("document.getElementsByTagName('body')[0].innerText", new ValueCallback<String>() {
#Override
public void onReceiveValue(String s) {
contentView.setText(s);
}
});
}
else {
webView.loadUrl("javascript:window.INTERFACE.processContent(document.getElementsByTagName('body')[0].innerText)");
}
}
});
webView.loadUrl("https://stackoverflow.com");

To call a JavaScript function from Android you don't need to add interface prefix:
webView.loadUrl("javascript:processContent(document.getElementsByTagName('body')[0].innerText);");
Note: You must implement the called javascript function in your HTML page. So If you are calling a third party website in your webview, you have only access to the current existing functions in that page.
e.g https://stackoverflow.com has no javascript function named INTERFACE.processContent!
On the contrary when you want to call and Android method from javascript then you need that prefix:
<script>INTERFACE.myAndroidMethod()</script>
Finally if you want to proccess the HTML content of a thirdparty webpage you can not extract the content using a Webview and JavaScript function (that not exists in that page) but you need Android codes to load the webpage content without the WebView mediation.

Android webview href not support in html page

I want to load to a about.html page inside asset folder by clicking a button in index.html inside android webview.
Here's the code:
Button:
About
Java:
WebView browser = (WebView) findViewById(webview);
browser.getSettings().setJavaScriptEnabled(true);
browser.setWebChromeClient(new WebChromeClient());
browser.loadUrl("file:///android_asset/www/index.html");
browser.setWebViewClient(new WebViewClient() {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(url);
return false;
}
});
But the problem is when i click on button it doesn't load about.html but if I add a javascript function with below code it works.. but i want to use href.
Code:
<button onclick="about()">About</button>
<script>
function about() {
location.href = "about.html";
}
</script>
How do I solve it?

write an interface for TagHandler and in your fromHtml method check for the tag and handle it by loading the page
https://developer.android.com/reference/android/text/Html.html

try this code:
private void loadWebView(WebView webView,String htmlString)
{
try {
final String mimeType = "text/html";
final String encoding = "UTF-8";
WebViewClient yourWebClient = new WebViewClient()
{
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url)
{
// This line we let me load only pages inside Webpage
if ( url.contains("") == true )
// Load new URL Don't override URL Link
return false;
// Return true to override url loading (In this case do nothing).
return true;
}
};
// Get Web view
webView.getSettings().setJavaScriptEnabled(true);
webView.getSettings().setSupportZoom(true);
webView.getSettings().setBuiltInZoomControls(true);
webView.setWebViewClient(yourWebClient);
// Load URL
webView.loadDataWithBaseURL("", htmlString, mimeType, encoding, "");
} catch (Exception e) {
e.printStackTrace();
}
}
use it as:
loadWebView(browser, "file:///android_asset/www/index.html") //pass url

Get href value from anchor tag in Android WebView when link is clicked

I am loading a webpage in WebView. There is a link in the webpage, which on desktop will download the file, but in the app the link should display a Toast saying the link is disabled for the app.
I am not sure how to get the value from href of the anchor tag, when the link is clicked.
<a class="btn btn-primary" download="http://xx.xxx.com/wp-content/uploads/2015/11/abc-27-15.mp3" href="http://xx.xxx.com/wp-content/uploads/2015/11/abc-27-15.mp3">
<i class="fa fa-download"></i> Download Audio</a>
Can someone share an idea or any sample code on how to do this.
EDIT:1
Here is what I am doing currently:
private static final String URL = "http://xx.xxx.com/wp-content/uploads/";
webView.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
WebView.HitTestResult hr = ((WebView) v).getHitTestResult();
String extra = hr.getExtra();
if (extra != null && extra.startsWith(URL) && extra.endsWith(".mp3")) {
Log.d("WebviewActivity", "Extra: " + extra);
Log.d("WebviewActivity", "Contains URL");
return true;
}
}
return false;
}
});
The problem with this approach is:
When i click on the link, i get the url in extra. It works fine till here. But, from next time, no matter where i click on the webview, the same extra is being returned. So even if i click on an image after i click on the url, i get the same url in the extra. Not sure if i doing anything wrong. Or is this the correct approach.
Please let me know if you need any details.
EDIT:2
private Handler mHandler = new Handler() {
#Override
public void handleMessage(Message msg) {
// Get link-URL.
String url = (String) msg.getData().get("url");
// Do something with it.
if (url != null) {
Log.d(TAG, "URL: "+url);
}
}
};
webView.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
WebView.HitTestResult hr = ((WebView) v).getHitTestResult();
if (hr.getType() == WebView.HitTestResult.SRC_ANCHOR_TYPE) {
Message msg = mHandler.obtainMessage();
webView.requestFocusNodeHref(msg);
}
}
return false;
}
});
webView.loadUrl(mUrl);
}
Now, i get the URL that is clicked in the last action_down event. How to get the current URL?
EDIT 3 (Attempt with webviewclient:
private class MyWebViewClient extends WebViewClient {
private static final String URL = "xx.xxx.com/wp-content/uploads/";
#Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {
super.onPageStarted(view, url, favicon);
if (!isFinishing())
mProgressDialog.show();
}
#Override
public void onPageFinished(WebView view, String url) {
super.onPageFinished(view, url);
mProgressDialog.dismiss();
}
#Override
public void onReceivedError(WebView view, int errorCode,
String description, String failingUrl) {
super.onReceivedError(view, errorCode, description, failingUrl);
Toast.makeText(WebviewActivity.this,
"Please check your internet " + "connection and try again",
Toast.LENGTH_SHORT).show();
}
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
Log.d("xxx", "Url: " + url);
if(url.contains(URL)) {
Log.d("xxx", "Url Contains: " + URL);
return true;
}
return false;
}
}
mMyWebViewClient = new MyWebViewClient();
webView.setWebViewClient(mMyWebViewClient);
Output in logcat when the link is clicked:
03-01 15:38:19.402 19626-19626/com.xx.xxx D/cr_Ime: [ImeAdapter.java:553] focusedNodeChanged: isEditable [false]
03-01 15:38:19.428 19626-19626/com.xx.xxx D/cr_Ime: [ImeAdapter.java:253] updateKeyboardVisibility: type [0->0], flags [0], show [true],
03-01 15:38:19.428 19626-19626/com.xx.xxx D/cr_Ime: [ImeAdapter.java:326] hideKeyboard
03-01 15:38:19.429 19626-19626/com.xx.xxx D/cr_Ime: [InputMethodManagerWrapper.java:56] isActive: true
03-01 15:38:19.429 19626-19626/com.xx.xxx D/cr_Ime: [InputMethodManagerWrapper.java:65] hideSoftInputFromWindow

Because you are using a WebView and the link is not Java script this is very easy to achieve with a WebViewClient which you can use to monitor your WebView
myWebView.setWebViewClient( new WebViewClient() {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
// check something unique to the urls you want to block
if (url.contains("xx.xxx.com")) {
Toast.make... //trigger the toast
return true; //with return true, the webview wont try rendering the url
}
return false; //let other links work normally
}
} );
It's possible that because your URL ends in .mp3 the file is being treated as a resource. You should also override the shouldInterceptRequest method of the WebViewClient to check this.
#Override
#TargetApi(Build.VERSION_CODES.LOLLIPOP)
public WebResourceResponse shouldInterceptRequest(WebView view, WebResourceRequest request) {
String url = request.getUrl().toString();
Log.d("XXX", "Url from API21 shouldInterceptRequest : " + url);
if (url.contains(URL)) {
return new WebResourceResponse("text/html", "UTF-8", "<html><body>No downloading from app</body></html>");
} else {
return null;
}
}
public WebResourceResponse shouldInterceptRequest (WebView view, String url) {
Log.d("XXX", "Url from shouldInterceptRequest : " + url);
if (url.contains(URL)) {
return new WebResourceResponse("text/html", "UTF-8", "<html><body>No downloading from app</body></html>");
} else {
return null;
}
}

Most of the work can be done at the web page side itself. You have to write java script to identify which device is accessing the page (mobile, desktop etc) if its mobile then use java script binding technique to call the native android code to show Toast message.
http://developer.android.com/guide/webapps/webview.html
WebView webView = (WebView) findViewById(R.id.webview);
webView.addJavascriptInterface(new WebAppInterface(this), "Android");
WebAppInterface.java
public class WebAppInterface {
Context mContext;
/** Instantiate the interface and set the context */
WebAppInterface(Context c) {
mContext = c;
}
/** Show a toast from the web page */
#JavascriptInterface
public void showToast(String toast) {
Toast.makeText(mContext, toast, Toast.LENGTH_SHORT).show();
}
}
YourHTML Page (this sample got a button click)
<input type="button" value="Say hello" onClick="showAndroidToast('Hello
Android!')" />
<script type="text/javascript">
function showAndroidToast(toast) {
Android.showToast(toast);
}
</script>

How to show local html file into webview?

I want show my local html file into webview .I use this codes :
WebView wv;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
wv=new WebView(this);
setContentView(wv);
try {
InputStream stream = this.getAssets().open("index.html");
int sreamsize = stream.available();
byte[] bufer = new byte[sreamsize];
stream.read(bufer);
stream.close();
String html= new String(bufer);
wv.loadData(html, "text/html", "UTF-8");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
Now I can see elements into webview with out css and js effect . How to solve this?

Try this:-
WebView wv;
wv = (WebView) findViewById(R.id.webView1);
WebSettings webViewSettings = wv.getSettings();
webViewSettings.setJavaScriptEnabled(true);
webViewSettings.setDomStorageEnabled(true);
wv.loadUrl("file:///android_asset/index.html");

Try this:-
WebView wv;
wv = (WebView) findViewById(R.id.webView1);
wv.loadUrl("file:///android_asset/index.html");

Try to replace
try {
InputStream stream = this.getAssets().open("index.html");
int sreamsize = stream.available();
byte[] bufer = new byte[sreamsize];
stream.read(bufer);
stream.close();
String html= new String(bufer);
wv.loadData(html, "text/html", "UTF-8");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
with
wv.loadUrl("file:///android_asset/index.html");
And try again.
Update
For JS get works perfectly
try
WebSettings webViewSettings = wv.getSettings();
webViewSettings.setJavaScriptEnabled(true);
webViewSettings.setDomStorageEnabled(true);
As #Sabari preferred.

Have you tried just doing wv.loadUrl("file:///android_asset/index.html");?

My JavaScript is not changing color or dimensions as I expected

I am trying to use JavaScript in an Android webview. I used following code. I did not get color changed or offset height of body.
webview.getSettings().setJavaScriptEnabled(true);
webview.addJavascriptInterface(new myJavaScriptInterface(webview), "jsInterface");
webview.loadUrl("file:///android_asset/sample/contents.html");
//webview.loadData("file:///android_asset/sample",convertStreamToString(inputStream), "text/html", "UTF-8");
webview.loadUrl("javascript:" +
"document.getElementsByTagName('p')[0].style.color='red';" +
"");
wbview.loadUrl("javascript:window.jsInterface.EchoText(document.body.offsetHeight);");
//webview.
}
class myJavaScriptInterface
{
WebView mywebview;
public myJavaScriptInterface(WebView webview)
{
this.mywebview=webview;
}
public void EchoText(String message)
{
Toast.makeText(mywebview.getContext(), message, Toast.LENGTH_SHORT).show();
}
}
What am I missing?

I think this is because your page is not loaded (still loading) when you are using webview.loadUrl("javascript:" + ...) statements.
Try the following...
webview.loadUrl("file:///android_asset/sample/contents.html");
webview.setWebViewClient(new WebViewClient() {
public void onPageFinished(WebView webview, String url) {
webview.loadUrl("javascript:" +
"document.getElementsByTagName('p')[0].style.color='red';");
wbview.loadUrl("javascript:" +
"window.jsInterface.EchoText(document.body.offsetHeight);");
}
});