如何将不同的图标添加到可扩展ListView中的子元素？

public class MyExpandableListAdapter extends BaseExpandableListAdapter {
    private Context context;
    private List<String> groups;
    private Map<String, List<String>> children;
    private Map<String, Integer> icons;

    public MyExpandableListAdapter(Context context, List<String> groups, Map<String, List<String>> children, Map<String, Integer> icons) {
        this.context = context;
        this.groups = groups;
        this.children = children;
        this.icons = icons;
    }

    @Override
    public int getGroupCount() {
        return groups.size();
    }

    @Override
    public int getChildrenCount(int groupPosition) {
        String group = groups.get(groupPosition);
        return children.get(group).size();
    }

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

    @Override
    public Object getChild(int groupPosition, int childPosition) {
        String group = groups.get(groupPosition);
        return children.get(group).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 true;
    }

    @Override
    public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
        if (convertView == null) {
            LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = inflater.inflate(R.layout.group_item_layout, null);
        }

        ImageView icon = convertView.findViewById(R.id.group_icon);
        String group = groups.get(groupPosition);
        int groupIconRes = icons.get(group);
        icon.setImageResource(groupIconRes);

        TextView groupName = convertView.findViewById(R.id.group_name);
        groupName.setText(group);

        return convertView;
    }

    @Override
    public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
        if (convertView == null) {
            LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = inflater.inflate(R.layout.child_item_layout, null);
        }

        ImageView icon = convertView.findViewById(R.id.child_icon);
        String group = groups.get(groupPosition);
        String child = children.get(group).get(childPosition);
        int childIconRes = icons.get(child);
        icon.setImageResource(childIconRes);

        TextView childName = convertView.findViewById(R.id.child_name);
        childName.setText(child);

        return convertView;
    }

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

// 创建数据源
List<String> groups = new ArrayList<>();
groups.add("Group 1");
groups.add("Group 2");

Map<String, List<String>> children = new HashMap<>();
List<String> children1 = new ArrayList<>();
children1.add("Child 1");
children1.add("Child 2");
List<String> children2 = new ArrayList<>();
children2.add("Child 3");
children2.add("Child 4");
children.put("Group 1", children1);
children.put("Group 2", children2);

Map<String, Integer> icons = new HashMap<>();
icons.put("Group 1", R.drawable.group_icon);
icons.put("Group 2", R.drawable.group_icon);
icons.put("Child 1", R.drawable.child_icon);
icons.put("Child 2", R.drawable.child_icon);
icons.put("Child 3", R.drawable.child_icon);
icons.put("Child 4", R.drawable.child_icon);

// 创建适配器
MyExpandableListAdapter adapter = new MyExpandableListAdapter(this, groups, children, icons);

// 设置适配器
ExpandableListView expandableListView = findViewById(R.id.expandable_list_view);
expandableListView.setAdapter(adapter);