Lets presume I want to add a <div>hello</div> a the bottom of the webpage http://www.google.com that I loaded in a WebView. Is it possible?
I can do it for an internal webpage (a page located on the internal memory of the device).
Here is the code of my Activity:
import android.app.Activity; import android.os.Bundle; import android.os.Handler; import android.webkit.WebView; import android.webkit.WebViewClient; import android.widget.Toast; public class Main extends Activity { private WebView mWebview; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); mWebview = new WebView(this); mWebview.getSettings().setJavaScriptEnabled(true); final Activity activity = this; mWebview.setWebViewClient(new WebViewClient() { public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) { Toast.makeText(activity, description, Toast.LENGTH_SHORT).show(); } private final String jsFileURL = "file:///android_asset/script.js"; @Override public void onPageFinished(WebView view, String url){ final WebView v = view; view.loadUrl("javascript:{" + "var script = document.createElement('script');" + "script.type = 'text/javascript';" + "script.src = '" + jsFileURL + "';" + "document.getElementsByTagName('head').item(0).appendChild(script); };"); new Handler().postDelayed(new Runnable() { @Override public void run() { v.loadUrl("javascript:job();"); } }, 100); } }); mWebview.loadUrl("file:///android_asset/page.html"); //mWebview.loadUrl("http://www.google.com"); setContentView(mWebview ); } } The content of script.js located in the "/assets" folder:
function job() { var div = document.createElement('div'); div.innerHTML = 'hello'; document.getElementsByTagName('body').item(0).appendChild(div); } And the content of page.html located in the "/assets" folder too:
<html> <head></head> <body> <div>content of my page</div> </body> </html> BUT
If I change
mWebview.loadUrl("file:///android_asset/page.html"); //mWebview.loadUrl("http://www.google.com"); by
//mWebview.loadUrl("file:///android_asset/page.html"); mWebview.loadUrl("http://www.google.com"); the trick doesn't work anymore... Is there a security reason?