android listview 二级菜单

Android中ListView的二级菜单可以通过嵌套ListView实现。具体步骤如下：

1. 创建一个主ListView并设置Adapter，Adapter中的数据包含一级菜单的内容；
2. 给主ListView的每个item设置点击事件，在点击事件中创建一个子ListView并设置Adapter，Adapter中的数据包含二级菜单的内容；
3. 将子ListView添加到主ListView的item中。

以下是一个简单的示例代码：

public class MainActivity extends AppCompatActivity {

    private ListView mListView;
    private List<String> mMainList;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        initData();
        initView();
    }

    private void initData() {
        mMainList = new ArrayList<>();
        mMainList.add("主菜单1");
        mMainList.add("主菜单2");
        mMainList.add("主菜单3");
    }

    private void initView() {
        mListView = findViewById(R.id.listview_main);
        MainAdapter mainAdapter = new MainAdapter();
        mListView.setAdapter(mainAdapter);
    }

    private class MainAdapter extends BaseAdapter {

        @Override
        public int getCount() {
            return mMainList.size();
        }

        @Override
        public Object getItem(int position) {
            return mMainList.get(position);
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ViewHolder holder;
            if (convertView == null) {
                convertView = LayoutInflater.from(MainActivity.this).inflate(R.layout.item_main, parent, false);
                holder = new ViewHolder();
                holder.tvMain = convertView.findViewById(R.id.tv_main);
                holder.lvSub = convertView.findViewById(R.id.lv_sub);
                convertView.setTag(holder);
            } else {
                holder = (ViewHolder) convertView.getTag();
            }

            final String mainText = mMainList.get(position);
            holder.tvMain.setText(mainText);
            holder.tvMain.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    SubAdapter subAdapter = new SubAdapter();
                    holder.lvSub.setAdapter(subAdapter);
                }
            });

            return convertView;
        }
    }

    private static class ViewHolder {
        TextView tvMain;
        ListView lvSub;
    }

    private class SubAdapter extends BaseAdapter {

        private List<String> mSubList;

        public SubAdapter() {
            mSubList = new ArrayList<>();
            mSubList.add("二级菜单1");
            mSubList.add("二级菜单2");
            mSubList.add("二级菜单3");
        }

        @Override
        public int getCount() {
            return mSubList.size();
        }

        @Override
        public Object getItem(int position) {
            return mSubList.get(position);
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            if (convertView == null) {
                convertView = LayoutInflater.from(MainActivity.this).inflate(R.layout.item_sub, parent, false);
            }

            String subText = mSubList.get(position);
            TextView tvSub = convertView.findViewById(R.id.tv_sub);
            tvSub.setText(subText);

            return convertView;
        }
    }
}

其中，item_main.xml和item_sub.xml分别对应主ListView的item布局和子ListView的item布局，可以根据自己的需求进行修改。