PhoneGap ใน Javascript จะเรียก Progress Dialog Loading ของ Android ยังไงครับ...???

public class MainActivity extends DroidGap {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        super.setIntegerProperty("splashscreen", R.drawable.splash);
        // Display a native loading dialog.  Format for value = "Title,Message".  
        // (String - default=null)
        super.setStringProperty("loadingDialog", "Wait,Loading Demo...");

       super.loadUrl("file:///android_asset/www/index.html");
      }
}