多級列表的實現

package com.example.expandable;

import java.util.ArrayList;
import java.util.List;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.ExpandableListView;
import android.widget.ExpandableListView.OnChildClickListener;
import android.widget.ExpandableListView.OnGroupClickListener;
import android.widget.Toast;

public class MainActivity extends Activity {
    private ExpandableListView expandableListView;
    private List<String> groupList;
    private List<List<String>> childList;
    private MyAdapter adapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        expandableListView = (ExpandableListView) findViewById(R.id.expandableListView);
        groupList = new ArrayList<String>();
        childList = new ArrayList<List<String>>();
        initDatas();
        adapter = new MyAdapter(this, groupList, childList);
        expandableListView.setAdapter(adapter);
        expandableListView.setGroupIndicator(getResources().getDrawable(R.drawable.expand_select));
        expandableListView.setOnGroupClickListener(new OnGroupClickListener() {
            
            @Override
            public boolean onGroupClick(ExpandableListView parent, View v,
                    int groupPosition, long id) {
                Toast.makeText(getApplicationContext(), groupList.get(groupPosition), 
                        Toast.LENGTH_SHORT).show();
                return false;
            }
        });
        expandableListView.setOnChildClickListener(new OnChildClickListener() {
            
            @Override
            public boolean onChildClick(ExpandableListView parent, View v,
                    int groupPosition, int childPosition, long id) {
                Toast.makeText(getApplicationContext(), childList.get(groupPosition).get(childPosition), 
                        Toast.LENGTH_SHORT).show();
                return false;
            }
        });
    }

    private void initDatas() {
        updateDatas("感興趣男明星", new String[] { "劉德華", "張學友", "郭富城" });
        updateDatas("感興趣女明星", new String[] { "劉亦菲", "張馨予", "郭采潔" });
    }

    private void updateDatas(String groupItem, String[] childs) {
        groupList.add(groupItem);
        List<String> childsItem = new ArrayList<String>();
        for (String item : childs) {
            childsItem.add(item);
        }
        childList.add(childsItem);
    }
}

package com.example.expandable;

import java.util.List;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.TextView;

public class MyAdapter extends BaseExpandableListAdapter {
    private Context context;
    private List<String> groupList;
    private List<List<String>> childList;
    private LayoutInflater layoutInflater;
    
    public MyAdapter(Context context, List<String> groupList,
            List<List<String>> childList) {
        this.context = context;
        this.groupList = groupList;
        this.childList = childList;
        this.layoutInflater = LayoutInflater.from(context);
    }

    @Override
    public int getGroupCount() {
        // TODO Auto-generated method stub
        return groupList.size();
    }

    @Override
    public int getChildrenCount(int groupPosition) {
        return childList.get(groupPosition).size();
    }

    @Override
    public Object getGroup(int groupPosition) {
        // TODO Auto-generated method stub
        return groupList.get(groupPosition);
    }

    @Override
    public Object getChild(int groupPosition, int childPosition) {
        // TODO Auto-generated method stub
        return childList.get(groupPosition).get(childPosition);
    }

    @Override
    public long getGroupId(int groupPosition) {
        // TODO Auto-generated method stub
        return groupPosition;
    }

    @Override
    public long getChildId(int groupPosition, int childPosition) {
        // TODO Auto-generated method stub
        return childPosition;
    }

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

    @Override
    public View getGroupView(int groupPosition, boolean isExpanded,
            View convertView, ViewGroup parent) {
        if (convertView==null) {
            convertView = layoutInflater.inflate(R.layout.group, parent,false);
        }
        TextView textView = (TextView) convertView.findViewById(R.id.tv_group);
        textView.setText(groupList.get(groupPosition));
        return convertView;
    }

    @Override
    public View getChildView(int groupPosition, int childPosition,
            boolean isLastChild, View convertView, ViewGroup parent) {
        if (convertView==null) {
            convertView = layoutInflater.inflate(R.layout.child, null);
        }
        TextView textView = (TextView) convertView.findViewById(R.id.tv_child);
        textView.setText(childList.get(groupPosition).get(childPosition));
        return convertView;
    }
    /**
     * 返回值爲true時   對child作出響應
     */
    @Override
    public boolean isChildSelectable(int groupPosition, int childPosition) {
        return true;
    }

}