wikitude image recognition in fragment

i always error

this my activity

public class ARActivity extends SherlockFragmentActivity {

ArchitectView arview;

@Override
protected void onCreate(Bundle arg0) {
    // TODO Auto-generated method stub
    super.onCreate(arg0);
    setContentView(R.layout.sample_cam);

    this.arview = (ArchitectView) findViewById(R.id.architectView);
    final ArchitectConfig config = new ArchitectConfig(
            WikitudeSDKConstants.WIKITUDE_SDK_KEY);
    this.arview.onCreate(config);

}

@Override
protected void onPostCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onPostCreate(savedInstanceState);

    this.arview.onPostCreate();
    try {
        this.arview.load("assets/wikitude/imageRecognition/index.html");
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

}

and this my xml

and i get error

please help me :(