Android之实现QQ好友分组(ExpandableListView)

在项目开发中，也许我们遇到过ListView中嵌套ListView，但谷歌建议我们最好别这样做，因此他们写好了一个ExpandableListView类，他继承ListView，可以实现ListView中嵌套ListView的效果，好了，废话不多说，先上效果图：

点击下载源码：仿QQ好友分组源代码

主代码：

public class ExListView extends Activity {
	private static final String GROUP_TEXT = "group_text";//大组成员Map的key
	private static final String CHILD_TEXT1 = "child_text1";//小组成员Map的第一个key
	private static final String CHILD_TEXT2 = "child_text2";//小组成员Map的第二个key

	List> groupData = new ArrayList>();//大组成员
	List>> childData = new ArrayList>>();//小组成员

	ExAdapter adapter;
	ExpandableListView exList;//可扩展的ListView

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		//为大小组中添加数据
		for (int i = 1; i < 6; i++) {
			Map curGroupMap = new HashMap();
			groupData.add(curGroupMap);
			curGroupMap.put(GROUP_TEXT, "第" + i + "大组");

			List> children = new ArrayList>();
			for (int j = 1; j < 6; j++) {
				Map curChildMap = new HashMap();
				children.add(curChildMap);
				curChildMap.put(CHILD_TEXT1, "第" + j + "小组");
				curChildMap.put(CHILD_TEXT2, "第" + j + "小组签名");
			}
			childData.add(children);
		}

		adapter = new ExAdapter(ExListView.this);
		exList = (ExpandableListView) findViewById(R.id.list);
		exList.setAdapter(adapter);
		exList.setGroupIndicator(null);//不设置大组指示器图标，因为我们自定义设置了
		exList.setDivider(null);//设置图片可拉伸的
	}
	//关键代码是这个可扩展的listView适配器
	class ExAdapter extends BaseExpandableListAdapter {
		Context context;

		public ExAdapter(Context context) {
			super();
			this.context = context;
		}
		//得到大组成员的view
		public View getGroupView(int groupPosition, boolean isExpanded,
				View convertView, ViewGroup parent) {
			View view = convertView;
			if (view == null) {
				LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
				view = inflater.inflate(R.layout.member_listview, null);
			}

			TextView title = (TextView) view.findViewById(R.id.content_001);
			title.setText(getGroup(groupPosition).toString());//设置大组成员名称

			ImageView image = (ImageView) view.findViewById(R.id.tubiao);//是否展开大组的箭头图标
			if (isExpanded)//大组展开时
				image.setBackgroundResource(R.drawable.btn_browser2);
			else//大组合并时
				image.setBackgroundResource(R.drawable.btn_browser);

			return view;
		}
		//得到大组成员的id
		public long getGroupId(int groupPosition) {
			return groupPosition;
		}
		//得到大组成员名称
		public Object getGroup(int groupPosition) {
			return groupData.get(groupPosition).get(GROUP_TEXT).toString();
		}
		//得到大组成员总数
		public int getGroupCount() {
			return groupData.size();

		}

		// 得到小组成员的view
		public View getChildView(int groupPosition, int childPosition,
				boolean isLastChild, View convertView, ViewGroup parent) {
			View view = convertView;
			if (view == null) {
				LayoutInflater inflater = LayoutInflater.from(context);
				view = inflater.inflate(R.layout.member_childitem, null);
			}
			final TextView title = (TextView) view
					.findViewById(R.id.child_text);
			title.setText(childData.get(groupPosition).get(childPosition)
					.get(CHILD_TEXT1).toString());//大标题
			final TextView title2 = (TextView) view
					.findViewById(R.id.child_text2);
			title2.setText(childData.get(groupPosition).get(childPosition)
					.get(CHILD_TEXT2).toString());//小标题

			return view;
		}
		//得到小组成员id
		public long getChildId(int groupPosition, int childPosition) {
			return childPosition;
		}
		//得到小组成员的名称
		public Object getChild(int groupPosition, int childPosition) {
			return childData.get(groupPosition).get(childPosition).get(CHILD_TEXT1)
					.toString();
		}
		//得到小组成员的数量
		public int getChildrenCount(int groupPosition) {
			return childData.get(groupPosition).size();
		}
		/**
	     * Indicates whether the child and group IDs are stable across changes to the
	     * underlying data.
	     * 表明大組和小组id是否稳定的更改底层数据。
	     * @return whether or not the same ID always refers to the same object
	     * @see Adapter#hasStableIds()
	     */
		public boolean hasStableIds() {
			return true;
		}
		//得到小组成员是否被选择
		public boolean isChildSelectable(int groupPosition, int childPosition) {
			return true;
		}

	}
}

主界面配置文件main.xml:

大组成员配置文件member_listview.xml：

小组成员配置文件member_childitem.xml：

好了，今天就到这里，中午休息一会。。。