Webview load html from assets directory

Whenever you are creating activity, you must add setcontentview(your layout) after super call. Because setcontentview bind xml into your activity so that's the reason you are getting nullpointerexception.

 setContentView(R.layout.webview);  
 webView = (WebView) findViewById(R.id.webView1);
 wv.loadUrl("file:///android_asset/xyz.html");

You are getting the WebView before setting the Content view so the wv is probably null.

public class ViewWeb extends Activity {  
        @Override  
        public void onCreate(Bundle savedInstanceState) {  
            super.onCreate(savedInstanceState);
            setContentView(R.layout.webview);  
            WebView wv;  
            wv = (WebView) findViewById(R.id.webView1);  
            wv.loadUrl("file:///android_asset/aboutcertified.html");   // now it will not fail here
        }  
    }