ExpandableListView点击出错

如题，我的group选项都没有child选项，然后一点击就会数组越界异常，错误指向适配器里的getChildrenCount方法。

public int getChildrenCount(int groupPosition) {
return child.get(groupPosition).size();
}

就这个了，哪个大神知道要怎么改啊，坐等

public Object getChild(int groupPosition, int childPosition) {
    if (childArray != null && childPosition < childArray.size()) {
        return childArray.get(groupPosition).get(childPosition);
    }
    return null;
}