2011.04.14——— android 可伸缩的listview 但不是ExpandableList

2011.04.14——— android 可伸缩的listview 但不是ExpandableList

这个activity的功能 就类似于经常见到的js手风琴菜单一样的效果


activity代码：

package com.lp.activity;

import java.util.List;

import android.app.ListActivity;
import android.content.Context;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;

import com.lp.bean.Help;
import com.lp.dao.HelpDao;

public class HelpActivity extends ListActivity {
	
	private HelpDao dao;
	private List<Help> helps;
	private boolean[] mExpanded;

	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		
		dao = new HelpDao(this);
		helps = dao.getAll();
		mExpanded = new boolean[helps.size()];
		for(int i=0;i<helps.size();i++){
			mExpanded[i] = false;
		}
		setListAdapter(new SpeechListAdapter(this));
	}
	
	

	@Override
	protected void onListItemClick(ListView l, View v, int position, long id) {
		((SpeechListAdapter)getListAdapter()).toggle(position);
	}



	//定义一个LinearLayout 上下结构  下面的textview可显示可隐藏
	private class SpeechView extends LinearLayout {
        public SpeechView(Context context, String title, String dialogue, boolean expanded) {
            super(context);
            
            this.setOrientation(VERTICAL);
            
            // Here we build the child views in code. They could also have
            // been specified in an XML file.
            
            mTitle = new TextView(context);
            //mTitle.setTextColor(R.color.title);
            mTitle.setTextColor(Color.RED);
            mTitle.setTextSize(20);
            mTitle.setText(title);
            addView(mTitle, new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));
            
            mDialogue = new TextView(context);
            mDialogue.setTextSize(15);
            mDialogue.setText(dialogue);
            addView(mDialogue, new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));
            
            mDialogue.setVisibility(expanded ? VISIBLE : GONE);
        }
        
        /**
         * Convenience method to set the title of a SpeechView
         */
        public void setTitle(String title) {
            mTitle.setText(title);
        }
        
        /**
         * Convenience method to set the dialogue of a SpeechView
         */
        public void setDialogue(String words) {
            mDialogue.setText(words);
        }
        
        /**
         * Convenience method to expand or hide the dialogue
         */
        public void setExpanded(boolean expanded) {
            mDialogue.setVisibility(expanded ? VISIBLE : GONE);
        }
        
        private TextView mTitle;
        private TextView mDialogue;
    }
	
	private class SpeechListAdapter extends BaseAdapter {
        public SpeechListAdapter(Context context)
        {
            mContext = context;
        }

        
        /**
         * The number of items in the list is determined by the number of speeches
         * in our array.
         * 
         * @see android.widget.ListAdapter#getCount()
         */
        public int getCount() {
            return helps.size();
        }

        /**
         * Since the data comes from an array, just returning
         * the index is sufficent to get at the data. If we
         * were using a more complex data structure, we
         * would return whatever object represents one 
         * row in the list.
         * 
         * @see android.widget.ListAdapter#getItem(int)
         */
        public Object getItem(int position) {
            return position;
        }

        /**
         * Use the array index as a unique id.
         * @see android.widget.ListAdapter#getItemId(int)
         */
        public long getItemId(int position) {
            return position;
        }

        /**
         * Make a SpeechView to hold each row.
         * @see android.widget.ListAdapter#getView(int, android.view.View, android.view.ViewGroup)
         */
        public View getView(int position, View convertView, ViewGroup parent) {
        	Help help = helps.get(position);
        	String name = help.getName();
        	String desc = help.getDescr();
            SpeechView sv;
            if (convertView == null) {
                sv = new SpeechView(mContext, name, desc, mExpanded[position]);
            } else {
                sv = (SpeechView)convertView;
                sv.setTitle(name);
                sv.setDialogue(desc);
                sv.setExpanded(mExpanded[position]);
            }
            
            return sv;
        }

        public void toggle(int position) {
            mExpanded[position] = !mExpanded[position];
            notifyDataSetChanged();
        }
        
        /**
         * Remember our context so we can use it when constructing views.
         */
        private Context mContext;
        
       
    }
	
}