public class ProgressTest extends Activity{

final Activity context = this;

@Override
public void onCreate(Bundle b) {
   super.onCreate(b);
   requestWindowFeature(Window.FEATURE_PROGRESS);//讓進度條顯示在標題欄上
   setContentView(R.layout.main);

   WebView webview = (WebView)findViewById(R.id.webview);
   webview.setWebChromeClient(new WebChromeClient() {
              public void onProgressChanged(WebView view, int progress) {
                //Activity和Webview根據(jù)加載程度決定進度條的進度大小
               //當加載到100%的時候 進度條自動消失
                context.setProgress(progress * 100);
       }
    });
   webview.loadUrl(url);
}