如何删除片段的默认按钮？

Question

我正在开发一个包含很多片段的应用，默认情况下，每个片段的左上角都有一个按钮。当我按下那个小按钮时，什么也没发生。如何删除？ 谢谢！

我什么都没尝试，但是我在想必须删除onButtonPressed方法，但是我不确定

这是片段的代码         包com.flixarts.ar。*;

    import android.content.Context;
    import android.net.Uri;
    import android.os.Bundle;
    import android.support.v4.app.Fragment;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.view.ViewGroup;


    /**
     * A simple {@link Fragment} subclass.
     * Activities that contain this fragment must implement the
     * {@link schoolfragment0.OnFragmentInteractionListener}     interface
     * to handle interaction events.
     * Use the {@link schoolfragment0#newInstance} factory method to
     * create an instance of this fragment.
     */
public class schoolfragment0 extends Fragment {
// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";

// TODO: Rename and change types of parameters
private String mParam1;
private String mParam2;

private OnFragmentInteractionListener mListener;

public schoolfragment0() {
    // Required empty public constructor
}

/**
 * Use this factory method to create a new instance of
 * this fragment using the provided parameters.
 *
 * @param param1 Parameter 1.
 * @param param2 Parameter 2.
 * @return A new instance of fragment schoolfragment0.
 */
// TODO: Rename and change types and number of parameters
public static schoolfragment0 newInstance(String param1, String param2) {
    schoolfragment0 fragment = new schoolfragment0();
    Bundle args = new Bundle();
    args.putString(ARG_PARAM1, param1);
    args.putString(ARG_PARAM2, param2);
    fragment.setArguments(args);
    return fragment;
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    if (getArguments() != null) {
        mParam1 = getArguments().getString(ARG_PARAM1);
        mParam2 = getArguments().getString(ARG_PARAM2);
    }
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    return inflater.inflate(R.layout.fragment_schoolfragment0, container, false);
}

// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
    if (mListener != null) {
        mListener.onFragmentInteraction(uri);
    }
}


@Override
public void onDetach() {
    super.onDetach();
    mListener = null;
}

/**
 * This interface must be implemented by activities that contain this
 * fragment to allow an interaction in this fragment to be communicated
 * to the activity and potentially other fragments contained in that
 * activity.
 * <p>
 * See the Android Training lesson <a href=
 * "http://developer.android.com/training/basics/fragments/communicating.html"
 * >Communicating with Other Fragments</a> for more information.
 */
public interface OnFragmentInteractionListener {
    // TODO: Update argument type and name
    void onFragmentInteraction(Uri uri);
}

}

我要删除左上角的灰色按钮

这是XML

<FrameLayout                  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=".schoolfragment0">

<!-- TODO: Update blank fragment layout -->
    <TextView
        android:id="@+id/espacioFrases"
        android:layout_width="325dp"
        android:layout_height="111dp"
        android:layout_gravity="center_horizontal"
        android:layout_marginTop="150dp"
        android:text=""
        android:textColor="@color/ColorPrimary"
        android:textSize="36sp" />

    <TextView
        android:id="@+id/espacioFrasesTraducidas"
        android:layout_width="307dp"
        android:layout_height="103dp"
        android:layout_gravity="center_horizontal"
        android:layout_marginTop="360dp"
        android:text=""
        android:textColor="@color/ColorPrimary"
        android:textSize="36sp" />

</FrameLayout>

在XML中，我有两个textview（我已经介绍了，抱歉，我找不到那个按钮在哪里）