expandablelistview学习在listView里面嵌套GridView

   在网上看到一个例子，讲android中的expandablelistview，是一种可以扩展的listview，就是那种点击一下可以扩展出子项，再点一下收缩回去的显示list。因为需要查看一堆文件的目录结构，就使用了expandablelist以便于直观地看到结构形式。
顶层是group，第二层是child。实现ExpandableListView至少需要下面两个类。

        一、ExpandableListView
　　　　一个垂直滚动的显示两个级别（Child,Group）列表项的视图，列表项来自ExpandableListAdapter 。组可以单独展开。
　　其所用到的重要方法如下：

          expandGroup(int groupPos) :在分组列表视图中展开一组，
　　　　　　setSelectedGroup(int groupPosition) ：设置选择指定的组。
　　　　　　setSelectedChild(int groupPosition, int childPosition, boolean shouldExpandGroup) ：设置选择指定的子项。
　　　　　　getPackedPositionGroup(long packedPosition) ：返回所选择的组
　　　　　　getPackedPositionForChild(int groupPosition, int childPosition) ：返回所选择的子项
　　　　　　getPackedPositionType(long packedPosition) ：返回所选择项的类型（Child,Group）
　　　　　　isGroupExpanded(int groupPosition) :判断此组是否展开

二、ExpandableListAdapter
　　　　一个接口，将基础数据链接到一个ExpandableListView。此接口的实施将提供访问Child的数据（由组分类），并实例化的Child和Group。
　　其里面重要方法：

getChildId(int groupPosition, int childPosition) 获取与在给定组给予孩子相关的数据。
　　　　getChildrenCount(int groupPosition) 返回在指定Group的Child数目。
        getChildView() 获取子视图（就是二级视图）
        getChildView()获取父视图

当我们想做到自己的打开或者关闭的标记时，可以先设置一个selector.xml，然后再用ExpandableListView的实例去调用setGroupIndicator(this.getResources().getDrawable(R.drawable.expand_list_selector));  这样就可以了。

下面就看下例子：

这个代码好像也是在eoe上下载下来的，具体也记不太清楚了，先看下效果图：

先给下代码，人家写的，咱们学习下：

public class ListViewActivity extends Activity
{
    ExpandableListView expandableListView;

    ListViewAdapter treeViewAdapter;

    public String[] groups = { "列表1", "列表2", "列表3" };

    public String[][] child = { { "" }, { "" }, { "", "" } };

    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        treeViewAdapter = new ListViewAdapter(this,
                ListViewAdapter.PaddingLeft >> 1);
        expandableListView = (ExpandableListView) this
        .findViewById(R.id.expandableListView);

        List<ListViewAdapter.TreeNode> treeNode = treeViewAdapter.GetTreeNode();
        for (int i = 0; i < groups.length; i++)
        {
            ListViewAdapter.TreeNode node = new ListViewAdapter.TreeNode();
            node.parent = groups[i];
            for (int ii = 0; ii < child[i].length; ii++)
            {
                node.childs.add(child[i][ii]);
            }
            treeNode.add(node);
        }

        treeViewAdapter.UpdateTreeNode(treeNode);
        expandableListView.setAdapter(treeViewAdapter);
    }

    
}

GridView的定义：

class MyGridView extends GridView
    {
        public MyGridView(android.content.Context context,
                android.util.AttributeSet attrs)
        {
            super(context, attrs);
        }

        /**
         * 设置不滚动
         */
        public void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
        {
            int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2,
            MeasureSpec.AT_MOST);
            super.onMeasure(widthMeasureSpec, expandSpec);
        }
    }

adapter的代码：

public class ListViewAdapter extends BaseExpandableListAdapter implements
        OnItemClickListener
{
    public static final int ItemHeight = 48;// 每项的高度
    public static final int PaddingLeft = 36;// 每项的高度
    private int myPaddingLeft = 0;
    private MyGridView toolbarGrid;
    private String menu_toolbar_name_array[] = { "存储卡", "我的下载", "图书导入", "系统备份",
            "系统恢复", "清除全部", "在线升级", "快速入门", "关于开卷", "退出系统", "在线升级", "快速入门",
            "关于开卷", "退出系统", "关于开卷", "退出系统", "关于开卷", "退出系统", "关于开卷", "退出系统" };
    private int menu_toolbar_image_array[] = { R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard };

    private List<TreeNode> treeNodes = new ArrayList<TreeNode>();
    private Context parentContext;
    private LayoutInflater layoutInflater;
    static public class TreeNode
    {
        Object parent;
        List<Object> childs = new ArrayList<Object>();
    }

    public ListViewAdapter(Context view, int myPaddingLeft)
    {
        parentContext = view;
        this.myPaddingLeft = myPaddingLeft;
    }

    public List<TreeNode> GetTreeNode()
    {
        return treeNodes;
    }

    public void UpdateTreeNode(List<TreeNode> nodes)
    {
        treeNodes = nodes;
    }

    public void RemoveAll()
    {
        treeNodes.clear();
    }

    public Object getChild(int groupPosition, int childPosition)
    {
        return treeNodes.get(groupPosition).childs.get(childPosition);
    }

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

    static public TextView getTextView(Context context)
    {
        AbsListView.LayoutParams lp = new AbsListView.LayoutParams(
                ViewGroup.LayoutParams.FILL_PARENT, ItemHeight);

        TextView textView = new TextView(context);
        textView.setLayoutParams(lp);
        textView.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);
        return textView;
    }

    /**
     * 可自定义ExpandableListView
     */
    public View getChildView(int groupPosition, int childPosition,
            boolean isLastChild, View convertView, ViewGroup parent)
    {
        if (convertView == null)
        {
            layoutInflater = (LayoutInflater) parentContext
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = layoutInflater.inflate(R.layout.view, null);

            toolbarGrid = (MyGridView) convertView
                    .findViewById(R.id.GridView_toolbar);
            toolbarGrid.setNumColumns(4);// 设置每行列数
            toolbarGrid.setGravity(Gravity.CENTER);// 位置居中
            toolbarGrid.setHorizontalSpacing(10);// 水平间隔
            toolbarGrid.setAdapter(getMenuAdapter(menu_toolbar_name_array,
                    menu_toolbar_image_array));// 设置菜单Adapter
            toolbarGrid.setOnItemClickListener(this);

        }
        return convertView;
    }

    /**
     * 可自定义list
     */
    public View getGroupView(int groupPosition, boolean isExpanded,
            View convertView, ViewGroup parent)
    {
        TextView textView = getTextView(this.parentContext);
        textView.setText(getGroup(groupPosition).toString());
        textView.setPadding(myPaddingLeft + PaddingLeft, 0, 0, 0);
        return textView;
    }

    public long getChildId(int groupPosition, int childPosition)
    {
        return childPosition;
    }

    public Object getGroup(int groupPosition)
    {
        return treeNodes.get(groupPosition).parent;
    }

    public int getGroupCount()
    {
        return treeNodes.size();
    }

    public long getGroupId(int groupPosition)
    {
        return groupPosition;
    }

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

    public boolean hasStableIds()
    {
        return true;
    }

    /**
     * 构造菜单Adapter
     * 
     * @param menuNameArray
     *            名称
     * @param imageResourceArray
     *            图片
     * @return SimpleAdapter
     */
    private SimpleAdapter getMenuAdapter(String[] menuNameArray,
            int[] imageResourceArray)
    {
        ArrayList<HashMap<String, Object>> data = new ArrayList<HashMap<String, Object>>();
        for (int i = 0; i < menuNameArray.length; i++)
        {
            HashMap<String, Object> map = new HashMap<String, Object>();
            map.put("itemImage", imageResourceArray[i]);
            map.put("itemText", menuNameArray[i]);
            data.add(map);
        }
        SimpleAdapter simperAdapter = new SimpleAdapter(parentContext, data,
                R.layout.item_menu, new String[] { "itemImage", "itemText" },
                new int[] { R.id.item_image, R.id.item_text });
        return simperAdapter;
    }

    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position,
            long id)
    {
        Toast.makeText(parentContext, "当前选中的是:" + position, Toast.LENGTH_SHORT)
                .show();

    }
}

里面比较简单的是listView，比较难的就是嵌套GridView吧!

定义文字和图片：

private String menu_toolbar_name_array[] = { "存储卡", "我的下载", "图书导入", "系统备份",
            "系统恢复", "清除全部", "在线升级", "快速入门", "关于开卷", "退出系统", "在线升级", "快速入门",
            "关于开卷", "退出系统", "关于开卷", "退出系统", "关于开卷", "退出系统", "关于开卷", "退出系统" };
    private int menu_toolbar_image_array[] = { R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard, R.drawable.icon_sdcard,
            R.drawable.icon_sdcard };

里面很重要的是那个node,一定要看理解：

public List<TreeNode> GetTreeNode()
    {
        return treeNodes;
    }

    public void UpdateTreeNode(List<TreeNode> nodes)
    {
        treeNodes = nodes;
    }

    public void RemoveAll()
    {
        treeNodes.clear();
    }

    public Object getChild(int groupPosition, int childPosition)
    {
        return treeNodes.get(groupPosition).childs.get(childPosition);
    }

    public int getChildrenCount(int groupPosition)
    {
        return treeNodes.get(groupPosition).childs.size();
    }
    
    public Object getGroup(int groupPosition)
    {
        return treeNodes.get(groupPosition).parent;
    }

    public int getGroupCount()
    {
        return treeNodes.size();
    }

adapter也挺简单：

private SimpleAdapter getMenuAdapter(String[] menuNameArray,
            int[] imageResourceArray)
    {
        ArrayList<HashMap<String, Object>> data = new ArrayList<HashMap<String, Object>>();
        for (int i = 0; i < menuNameArray.length; i++)
        {
            HashMap<String, Object> map = new HashMap<String, Object>();
            map.put("itemImage", imageResourceArray[i]);
            map.put("itemText", menuNameArray[i]);
            data.add(map);
        }
        SimpleAdapter simperAdapter = new SimpleAdapter(parentContext, data,
                R.layout.item_menu, new String[] { "itemImage", "itemText" },
                new int[] { R.id.item_image, R.id.item_text });
        return simperAdapter;
    }

代码：https://files.cnblogs.com/shanzei/ListView%E5%86%85%E5%B5%8CGridView.zip

网上还有其他例子，可以一并学习下：

Android自定义ExpandableListView

用户界面View

Android版手风琴（ExpandableListView）

ExpandableListView使用及数据更新

用ExpandableListView实现类似QQ好友列表

原文：http://blog.csdn.net/aomandeshangxiao/article/details/7163457