2013.01.03 （2）——— android开发实例之仿QQExpandableListView

2013.01.03 （2）——— android开发实例之仿QQExpandableListView
参考：http://blog.csdn.net/way_ping_li/article/details/9090793


自定义的ExpandableListView

package com.example.testiphonetreeview;

import android.content.Context;
import android.graphics.Canvas;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.ExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.ExpandableListView.OnGroupClickListener;

public class IphoneTreeView extends ExpandableListView implements
		OnScrollListener, OnGroupClickListener {
	public IphoneTreeView(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		registerListener();
	}

	public IphoneTreeView(Context context, AttributeSet attrs) {
		super(context, attrs);
		registerListener();
	}

	public IphoneTreeView(Context context) {
		super(context);
		registerListener();
	}

	/**
	 * Adapter 接口 . 列表必须实现此接口 .
	 */
	public interface IphoneTreeHeaderAdapter {
		public static final int PINNED_HEADER_GONE = 0;
		public static final int PINNED_HEADER_VISIBLE = 1;
		public static final int PINNED_HEADER_PUSHED_UP = 2;

		/**
		 * 获取 Header 的状态
		 * 
		 * @param groupPosition
		 * @param childPosition
		 * @return 
		 *         PINNED_HEADER_GONE,PINNED_HEADER_VISIBLE,PINNED_HEADER_PUSHED_UP
		 *         其中之一
		 */
		int getTreeHeaderState(int groupPosition, int childPosition);

		/**
		 * 配置 QQHeader, 让 QQHeader 知道显示的内容
		 * 
		 * @param header
		 * @param groupPosition
		 * @param childPosition
		 * @param alpha
		 */
		void configureTreeHeader(View header, int groupPosition,
				int childPosition, int alpha);

		/**
		 * 设置组按下的状态
		 * 
		 * @param groupPosition
		 * @param status
		 */
		void onHeadViewClick(int groupPosition, int status);

		/**
		 * 获取组按下的状态
		 * 
		 * @param groupPosition
		 * @return
		 */
		int getHeadViewClickStatus(int groupPosition);

	}

	private static final int MAX_ALPHA = 160;

	private IphoneTreeHeaderAdapter mAdapter;

	/**
	 * 用于在列表头显示的 View,mHeaderViewVisible 为 true 才可见
	 */
	private View mHeaderView;

	/**
	 * 列表头是否可见
	 */
	private boolean mHeaderViewVisible;

	private int mHeaderViewWidth;

	private int mHeaderViewHeight;
	
	private OnScrollListener mOnScrollListener;

	public void setHeaderView(View view) {
		mHeaderView = view;
		AbsListView.LayoutParams lp = new AbsListView.LayoutParams(
				ViewGroup.LayoutParams.MATCH_PARENT,
				ViewGroup.LayoutParams.WRAP_CONTENT);
		view.setLayoutParams(lp);

		if (mHeaderView != null) {
			setFadingEdgeLength(0);
		}

		requestLayout();
	}

	private void registerListener() {
		super.setOnScrollListener(this);
		setOnGroupClickListener(this);
	}

	/**
	 * 点击 HeaderView 触发的事件
	 */
	private void headerViewClick() {
		long packedPosition = getExpandableListPosition(this
				.getFirstVisiblePosition());

		int groupPosition = ExpandableListView
				.getPackedPositionGroup(packedPosition);

		if (mAdapter.getHeadViewClickStatus(groupPosition) == 1) {
			this.collapseGroup(groupPosition);
			mAdapter.onHeadViewClick(groupPosition, 0);
		} else {
			this.expandGroup(groupPosition);
			mAdapter.onHeadViewClick(groupPosition, 1);
		}

		this.setSelectedGroup(groupPosition);
	}

	private float mDownX;
	private float mDownY;

	/**
	 * 如果 HeaderView 是可见的 , 此函数用于判断是否点击了 HeaderView, 并对做相应的处理 , 因为 HeaderView
	 * 是画上去的 , 所以设置事件监听是无效的 , 只有自行控制 .
	 */
	@Override
	public boolean onTouchEvent(MotionEvent ev) {
		if (mHeaderViewVisible) {
			switch (ev.getAction()) {
			case MotionEvent.ACTION_DOWN:
				mDownX = ev.getX();
				mDownY = ev.getY();
				if (mDownX <= mHeaderViewWidth && mDownY <= mHeaderViewHeight) {
					return true;
				}
				break;
			case MotionEvent.ACTION_UP:
				float x = ev.getX();
				float y = ev.getY();
				float offsetX = Math.abs(x - mDownX);
				float offsetY = Math.abs(y - mDownY);
				// 如果 HeaderView 是可见的 , 点击在 HeaderView 内 , 那么触
				// 发 headerClick()
				if (x <= mHeaderViewWidth && y <= mHeaderViewHeight
						&& offsetX <= mHeaderViewWidth
						&& offsetY <= mHeaderViewHeight) {
					if (mHeaderView != null) {
						headerViewClick();
					}

					return true;
				}
				break;
			default:
				break;
			}
		}

		return super.onTouchEvent(ev);

	}

	@Override
	public void setAdapter(ExpandableListAdapter adapter) {
		super.setAdapter(adapter);
		mAdapter = (IphoneTreeHeaderAdapter) adapter;
	}

	/**
	 * 
	 * 点击了 Group 触发的事件 , 要根据根据当前点击 Group 的状态来
	 */
	@Override
	public boolean onGroupClick(ExpandableListView parent, View v,
			int groupPosition, long id) {
		if (mAdapter.getHeadViewClickStatus(groupPosition) == 0) {
			parent.expandGroup(groupPosition);
			mAdapter.onHeadViewClick(groupPosition, 1);
		} else if (mAdapter.getHeadViewClickStatus(groupPosition) == 1) {
			parent.collapseGroup(groupPosition);
			mAdapter.onHeadViewClick(groupPosition, 0);
		}

		return true;

	}

	@Override
	protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
		super.onMeasure(widthMeasureSpec, heightMeasureSpec);
		if (mHeaderView != null) {
			measureChild(mHeaderView, widthMeasureSpec, heightMeasureSpec);
			mHeaderViewWidth = mHeaderView.getMeasuredWidth();
			mHeaderViewHeight = mHeaderView.getMeasuredHeight();
		}
	}

	private int mOldState = -1;

	@Override
	protected void onLayout(boolean changed, int left, int top, int right,
			int bottom) {
		super.onLayout(changed, left, top, right, bottom);
		final long flatPostion = getExpandableListPosition(getFirstVisiblePosition());
		final int groupPos = ExpandableListView
				.getPackedPositionGroup(flatPostion);
		final int childPos = ExpandableListView
				.getPackedPositionChild(flatPostion);
		int state = mAdapter.getTreeHeaderState(groupPos, childPos);
		if (mHeaderView != null && mAdapter != null && state != mOldState) {
			mOldState = state;
			mHeaderView.layout(0, 0, mHeaderViewWidth, mHeaderViewHeight);
		}

		configureHeaderView(groupPos, childPos);
	}

	public void configureHeaderView(int groupPosition, int childPosition) {
		if (mHeaderView == null || mAdapter == null
				|| ((ExpandableListAdapter) mAdapter).getGroupCount() == 0) {
			return;
		}
		int state = mAdapter.getTreeHeaderState(groupPosition, childPosition);

		switch (state) {
		case IphoneTreeHeaderAdapter.PINNED_HEADER_GONE: {
			mHeaderViewVisible = false;
			break;
		}

		case IphoneTreeHeaderAdapter.PINNED_HEADER_VISIBLE: {
			mAdapter.configureTreeHeader(mHeaderView, groupPosition,
					childPosition, MAX_ALPHA);

			if (mHeaderView.getTop() != 0) {
				mHeaderView.layout(0, 0, mHeaderViewWidth, mHeaderViewHeight);
			}

			mHeaderViewVisible = true;

			break;
		}

		case IphoneTreeHeaderAdapter.PINNED_HEADER_PUSHED_UP: {
			View firstView = getChildAt(0);
			int bottom = firstView.getBottom();

			// intitemHeight = firstView.getHeight();
			int headerHeight = mHeaderView.getHeight();

			int y;

			int alpha;

			if (bottom < headerHeight) {
				y = (bottom - headerHeight);
				alpha = MAX_ALPHA * (headerHeight + y) / headerHeight;
			} else {
				y = 0;
				alpha = MAX_ALPHA;
			}

			mAdapter.configureTreeHeader(mHeaderView, groupPosition,
					childPosition, alpha);

			if (mHeaderView.getTop() != y) {
				mHeaderView.layout(0, y, mHeaderViewWidth, mHeaderViewHeight
						+ y);
			}

			mHeaderViewVisible = true;
			break;
		}
		}
	}

	@Override
	/**
	 * 列表界面更新时调用该方法(如滚动时)
	 */
	protected void dispatchDraw(Canvas canvas) {
		super.dispatchDraw(canvas);
		if (mHeaderViewVisible) {
			// 分组栏是直接绘制到界面中，而不是加入到ViewGroup中
			drawChild(canvas, mHeaderView, getDrawingTime());
		}
	}

	@Override
	public void onScroll(AbsListView view, int firstVisibleItem,
			int visibleItemCount, int totalItemCount) {
		if(mOnScrollListener!=null){
			mOnScrollListener.onScroll(view, firstVisibleItem, visibleItemCount, totalItemCount);
		}
		final long flatPos = getExpandableListPosition(firstVisibleItem);
		int groupPosition = ExpandableListView.getPackedPositionGroup(flatPos);
		int childPosition = ExpandableListView.getPackedPositionChild(flatPos);
		System.out.println("onScroll=============groupPosition: " + groupPosition + ", childPosition: " + childPosition);

		configureHeaderView(groupPosition, childPosition);
	}

	@Override
	public void onScrollStateChanged(AbsListView view, int scrollState) {
		if(mOnScrollListener!=null){
			mOnScrollListener.onScrollStateChanged(view, scrollState);
		}
	}
	
	
	@Override
	public void setOnScrollListener(OnScrollListener l) {
		mOnScrollListener = l;
	}
}

MainActivity.java

package com.example.testiphonetreeview;

import java.util.HashMap;

import android.app.Activity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import com.example.testiphonetreeview.IphoneTreeView.IphoneTreeHeaderAdapter;

public class MainActivity extends Activity {
	private IphoneTreeView iphoneTreeView;  
	private LayoutInflater mInflater;  
	private IphoneTreeViewAdapter mAdp;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		initView();
	}
	private void initView(){
		mInflater = LayoutInflater.from(this);  
		iphoneTreeView = (IphoneTreeView) findViewById(R.id.iphone_tree_view);  
        iphoneTreeView.setHeaderView(getLayoutInflater().inflate(  
                R.layout.contact_buddy_list_group, iphoneTreeView, false));  
        iphoneTreeView.setGroupIndicator(null); 
        mAdp = new IphoneTreeViewAdapter();
        iphoneTreeView.setAdapter(mAdp);
	}
	
	
	public class IphoneTreeViewAdapter extends BaseExpandableListAdapter
			implements IphoneTreeHeaderAdapter {
		// Sample data set. children[i] contains the children (String[]) for
		// groups[i].
		private HashMap<Integer, Integer> groupStatusMap;
		private String[] groups = { "第一组", "第二组", "第三组", "第四组", "第五组", "第六组", "第七组", "第八组" };
		private String[][] children = {
				{ "Way", "Arnold", "Barry", "Chuck", "David", "Afghanistan",
						"Albania", "Belgium", "Lily", "Jim", "LiMing", "Jodan" },
				{ "Ace", "Bandit", "Cha-Cha", "Deuce", "Bahamas", "China",
						"Dominica", "Jim", "LiMing", "Jodan" },
				{ "Fluffy", "Snuggles", "Ecuador", "Ecuador", "Jim", "LiMing",
						"Jodan" },
				{ "Goldy", "Bubbles", "Iceland", "Iran", "Italy", "Jim",
						"LiMing", "Jodan" },
				{ "Goldy", "Bubbles", "Iceland", "Iran", "Italy", "Jim",
					"LiMing", "Jodan" },
				{ "Goldy", "Bubbles", "Iceland", "Iran", "Italy", "Jim",
					"LiMing", "Jodan" },
				{ "Goldy", "Bubbles", "Iceland", "Iran", "Italy", "Jim",
					"LiMing", "Jodan" },
				{ "Fluffy", "Bubbles", "Iceland", "Iran", "Italy", "Jim",
					"LiMing", "Snuggles" }};

		public IphoneTreeViewAdapter() {
			// TODO Auto-generated constructor stub
			groupStatusMap = new HashMap<Integer, Integer>();
		}

		public Object getChild(int groupPosition, int childPosition) {
			return children[groupPosition][childPosition];
		}

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

		public int getChildrenCount(int groupPosition) {
			return children[groupPosition].length;
		}

		public Object getGroup(int groupPosition) {
			return groups[groupPosition];
		}

		public int getGroupCount() {
			return groups.length;
		}

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

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

		public boolean hasStableIds() {
			return true;
		}

		@Override
		public View getChildView(int groupPosition, int childPosition,
				boolean isLastChild, View convertView, ViewGroup parent) {
			// TODO Auto-generated method stub
			if (convertView == null) {
				convertView = mInflater.inflate(R.layout.contact_list_item_for_buddy, null);
			}
			TextView tv = (TextView) convertView
					.findViewById(R.id.contact_list_item_name);
			tv.setText(getChild(groupPosition, childPosition).toString());
			TextView state = (TextView) convertView
					.findViewById(R.id.cpntact_list_item_state);
			state.setText("爱生活...爱Android...");
			return convertView;
		}

		@Override
		public View getGroupView(int groupPosition, boolean isExpanded,
				View convertView, ViewGroup parent) {
			// TODO Auto-generated method stub
			if (convertView == null) {
				convertView = mInflater.inflate(R.layout.contact_buddy_list_group, null);
			}
			TextView groupName = (TextView) convertView
					.findViewById(R.id.group_name);
			groupName.setText(groups[groupPosition]);

			ImageView indicator = (ImageView) convertView
					.findViewById(R.id.group_indicator);
			TextView onlineNum = (TextView) convertView
					.findViewById(R.id.online_count);
			onlineNum.setText(getChildrenCount(groupPosition) + "/"
					+ getChildrenCount(groupPosition));
			if (isExpanded) {
				indicator.setImageResource(R.drawable.indicator_expanded);
			} else {
				indicator.setImageResource(R.drawable.indicator_unexpanded);
			}
			return convertView;
		}

		@Override
		public int getTreeHeaderState(int groupPosition, int childPosition) {
			final int childCount = getChildrenCount(groupPosition);
			System.out.println("getTreeHeaderState=============groupPosition: " + groupPosition 
					+ ", childPosition: " + childPosition + ", childCount: " + childCount);
			if (childPosition == childCount - 1) {
				System.out.println("=================PINNED_HEADER_PUSHED_UP======================");
				return PINNED_HEADER_PUSHED_UP;
			} else if (childPosition == -1
					&& !iphoneTreeView.isGroupExpanded(groupPosition)) {
				System.out.println("=================PINNED_HEADER_GONE======================");
				return PINNED_HEADER_GONE;
			} else {
				System.out.println("=================PINNED_HEADER_VISIBLE======================");
				return PINNED_HEADER_VISIBLE;
			}
		}

		@Override
		public void configureTreeHeader(View header, int groupPosition,
				int childPosition, int alpha) {
			// TODO Auto-generated method stub
			((TextView) header.findViewById(R.id.group_name))
					.setText(groups[groupPosition]);
			((TextView) header.findViewById(R.id.online_count))
					.setText(getChildrenCount(groupPosition) + "/"
							+ getChildrenCount(groupPosition));
			header.getBackground().setAlpha(alpha);
		}

		@Override
		public void onHeadViewClick(int groupPosition, int status) {
			// TODO Auto-generated method stub
			groupStatusMap.put(groupPosition, status);
		}

		@Override
		public int getHeadViewClickStatus(int groupPosition) {
			if (groupStatusMap.containsKey(groupPosition)) {
				return groupStatusMap.get(groupPosition);
			} else {
				return 0;
			}
		}

	}
}

布局文件就不贴了，会附上源码，效果图如下