如何禁用展开式列表视图图标

Question

我想在导航抽屉上禁用可展开列表视图项。 现在，我使用以下代码禁用列表视图上的可扩展列表视图图标：

 android:groupIndicator="@null"

但这不是我想要的。如果该项目有子菜单，我想要Icon。如果没有子菜单，则不应该有可扩展的列表视图图标。那是我的List Adapter。有谁知道，如何实现它？

public class ExpandableListAdapter extends BaseExpandableListAdapter {
    private Context mContext;
    private List<ExpandedMenuModel> mListDataHeader; // header titles

    // child data in format of header title, child title
    private HashMap<ExpandedMenuModel, List<String>> mListDataChild;
    ExpandableListView expandList;

    public ExpandableListAdapter(Context context, List<ExpandedMenuModel> listDataHeader, HashMap<ExpandedMenuModel, List<String>> listChildData, ExpandableListView mView) {
        this.mContext = context;
        this.mListDataHeader = listDataHeader;
        this.mListDataChild = listChildData;
        this.expandList = mView;
    }

    @Override
    public int getGroupCount() {
        int i = mListDataHeader.size();
        Log.d("GROUPCOUNT", String.valueOf(i));
        return this.mListDataHeader.size();
    }

    @Override
    public int getChildrenCount(int groupPosition) {
        int childCount = 0;
        if (groupPosition != 1) {   //War ursprünglich != 2 !!!
            childCount = this.mListDataChild.get(this.mListDataHeader.get(groupPosition))
                    .size();
        }
        return childCount;
    }

    @Override
    public Object getGroup(int groupPosition) {
        return this.mListDataHeader.get(groupPosition);
    }

    @Override
    public Object getChild(int groupPosition, int childPosition) {
        Log.d("CHILD", mListDataChild.get(this.mListDataHeader.get(groupPosition))
                .get(childPosition).toString());
        return this.mListDataChild.get(this.mListDataHeader.get(groupPosition))
                .get(childPosition);
    }

    @Override
    public long getGroupId(int groupPosition) {
        return groupPosition;
    }

    @Override
    public long getChildId(int groupPosition, int childPosition) {
        return childPosition;
    }

    @Override
    public boolean hasStableIds() {
        return false;
    }

    @Override
    public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
        ExpandedMenuModel headerTitle = (ExpandedMenuModel) getGroup(groupPosition);
        if (convertView == null) {
            LayoutInflater infalInflater = (LayoutInflater) this.mContext
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = infalInflater.inflate(R.layout.listheader, null);
        }
        TextView lblListHeader = (TextView) convertView
                .findViewById(R.id.submenu);

        lblListHeader.setTypeface(null, Typeface.BOLD);
        lblListHeader.setText(headerTitle.getIconName());

        return convertView;
    }

    @Override
    public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
        final String childText = (String) getChild(groupPosition, childPosition);

        if (convertView == null) {
            LayoutInflater infalInflater = (LayoutInflater) this.mContext
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = infalInflater.inflate(R.layout.list_submenu, null);
        }

        TextView txtListChild = (TextView) convertView
                .findViewById(R.id.submenu);

        txtListChild.setText(childText);

        return convertView;
    }

    @Override
    public boolean isChildSelectable(int groupPosition, int childPosition) {
        return true;
    }
}