Android 可展开列表组件 ExpandableListView

ExpandableListView 是ListView的子类,它把应用中的列表项分为几组,每组里可包含多个列表项. 所显示的列表项应该由ExpandableListAdapter 接口提供,实现ExpandableListAdapter有三种常用方式:

扩展BaseExpandableListAdapter 实现 ExpandableListAdapter ;

使用SimpleExpandableListAdapter 将两个list 集合包装成ExpandableListAdapter;

使用SimpleCursorTreeAdapter 将Cursor中的数据包装成SimpleCursorTreeAdapter;

ExpandableListView 支持常用属性:

android:childDivider 指定各组内各子列表的分割条

android:childIndicator 显示在子列表项旁边的Drawable 对象

android:groupIndicator 显示在组列表项旁边的Drawable对象.

public class ExpandableListViewTest extends Activity
{
	@Override
	public void onCreate(Bundle savedInstanceState)
	{
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		//创建一个BaseExpandableListAdapter对象
		ExpandableListAdapter adapter = new BaseExpandableListAdapter()
		{
			int[] logos = new int[]
			{
				R.drawable.p,
				R.drawable.z,
				R.drawable.t
			};
 			private String[] armTypes = new String[]
				{ "神族兵种", "虫族兵种", "人族兵种"};
			private String[][] arms = new String[][]
			{
				{ "狂战士", "龙骑士", "黑暗圣堂", "电兵" },
				{ "小狗", "刺蛇", "飞龙", "自爆飞机" },
				{ "机枪兵", "护士MM" , "幽灵" }
			};
			// 获取指定组位置、指定子列表项处的子列表项数据
			@Override
			public Object getChild(int groupPosition, int childPosition)
			{
				return arms[groupPosition][childPosition];
			}

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

			@Override
			public int getChildrenCount(int groupPosition)
			{
				return arms[groupPosition].length;
			}

			private TextView getTextView()
			{
				AbsListView.LayoutParams lp = new AbsListView.LayoutParams(
						ViewGroup.LayoutParams.MATCH_PARENT, 64);
				TextView textView = new TextView(ExpandableListViewTest.this);
				textView.setLayoutParams(lp);
				textView.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);
				textView.setPadding(36, 0, 0, 0);
				textView.setTextSize(20);
				return textView;
			}

			// 该方法决定每个子选项的外观
			@Override
			public View getChildView(int groupPosition, int childPosition,
					boolean isLastChild, View convertView, ViewGroup parent)
			{
				TextView textView = getTextView();
				textView.setText(getChild(groupPosition, childPosition)
						.toString());
				return textView;
			}

			// 获取指定组位置处的组数据
			@Override
			public Object getGroup(int groupPosition)
			{
				return armTypes[groupPosition];
			}

			@Override
			public int getGroupCount()
			{
				return armTypes.length;
			}

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

			// 该方法决定每个组选项的外观
			@Override
			public View getGroupView(int groupPosition, boolean isExpanded,
					View convertView, ViewGroup parent)
			{
				LinearLayout ll = new LinearLayout(ExpandableListViewTest.this);
				ll.setOrientation(0);
				ImageView logo = new ImageView(ExpandableListViewTest.this);
				logo.setImageResource(logos[groupPosition]);
				ll.addView(logo);
				TextView textView = getTextView();
				textView.setText(getGroup(groupPosition).toString());
				ll.addView(textView);
				return ll;
			}

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

			@Override
			public boolean hasStableIds()
			{
				return true;
			}
		};
		ExpandableListView expandListView = (ExpandableListView) findViewById(R.id.list);
		expandListView.setAdapter(adapter);
	}
}