public class MainActivity extends Activity implements CordovaInterface{
 .....
 .....
 public void changeText(String txt){
    textView = (TextView) findViewById(R.id.textView);
    textView.setText(txt);

 }

}

public boolean execute(String action, JSONArray args, final CallbackContext callbackContext){
          if (action.equals("changeText")) {
                      ..............
                 }
  }
}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >

   <org.apache.cordova.CordovaWebView
       android:id="@+id/tutorialView"
       android:layout_width="match_parent"
       android:layout_height="196dp" />

   <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" />

</RelativeLayout>

cordova.getActivity().runOnUiThread(new Runnable(){
 public void run() {

                textView.setText("Cordova Hello World");

                callbackContext.success();

                // Thread-safe.

        } });