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Android为ListView的Item设置不同的布局

MainActivity如下:
 
 
package cc.testlistview;  
import java.util.ArrayList;  
import java.util.HashMap;  
import android.os.Bundle;  
import android.view.View;  
import android.widget.AdapterView;  
import android.widget.AdapterView.OnItemClickListener;  
import android.widget.ListView;  
import android.app.Activity;  
/** 
 * Demo描述: 
 * 为ListView的Item设置不同的布局. 
 * 例如在该例子中ListView的第一个Item显示一张 
 * 图片,其余的Item都显示文字. 
 *  
 * 为了达到此目的需要重写BaseAdapter中的 
 * 1 getViewTypeCount()和getItemViewType(int position)方法. 
 *   1.1在getViewTypeCount中指定一共有几种不同的item 
 *      在此返回2即可. 
 *   1.2在getItemViewType(int position)中需要依据position的不同 
 *      返回不同的Type. 
 * 2 在getView()方法中针对不同的Type为Item设置布局 
 *   2.1得到当前位置(position)时的Type即代码: 
 *       currentType= getItemViewType(position); 
 *   2.2依据Type的不同为Item设置布局 
 *  
 * 参考资料: 
 * 1 http://blog.csdn.net/yueyue369/article/details/6115552 
 * 2 http://blog.sina.com.cn/s/blog_5da93c8f0100wx4v.html 
 *   Thank you very much 
 */  
public class MainActivity extends Activity {  
    private ListView mListView;  
    private HashMap<String, Object> mHashMap;  
    private ArrayList<HashMap<String, Object>> mArrayList;  
    @Override  
    protected void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.main);  
        init();  
    }  
    private void init(){  
        mArrayList=new ArrayList<HashMap<String,Object>>();  
        mListView=(ListView) findViewById(R.id.listview);  
        addDataForListView();  
        mListView.setAdapter  
        (new ListViewAdapter(MainActivity.this, mArrayList, R.layout.othersitem, new String []{"content"}, new int []{R.id.textView}));  
        mListView.setOnItemClickListener(new ItemClickListenerImpl());  
    }  
    private void addDataForListView(){  
        for (int i = 0; i < 30; i++) {  
            mHashMap=new HashMap<String, Object>();  
            mHashMap.put("content", "This is ---> "+i);  
            mArrayList.add(mHashMap);  
        }  
    }  
  
    private class ItemClickListenerImpl implements OnItemClickListener {  
        @Override  
        public void onItemClick(AdapterView<?> parent, View view, int position,long arg) {  
            System.out.println("OnItemClickListener position="+position);  
  
        }  
    }  
}  

 

 
ListViewAdapter如下:
 
package cc.testlistview;  
import java.util.List;  
import java.util.Map;  
import android.content.Context;  
import android.view.LayoutInflater;  
import android.view.View;  
import android.view.View.OnClickListener;  
import android.view.ViewGroup;  
import android.widget.BaseAdapter;  
import android.widget.ImageView;  
import android.widget.TextView;  
  
public class ListViewAdapter extends BaseAdapter {  
    private List<? extends Map<String, ?>> mArrayList;  
    private int resource;  
    private LayoutInflater mLayoutInflater;  
      
    private final int TYPE_COUNT=2;  
    private final int FIRST_TYPE=0;  
    private final int OTHERS_TYPE=1;  
    private int currentType;  
    public ListViewAdapter(Context context,List<? extends Map<String, ?>> data, int resource, String[] from,int[] to) {  
        this.mArrayList=data;  
        this.resource=resource;  
        mLayoutInflater=(LayoutInflater) context.getSystemService(context.LAYOUT_INFLATER_SERVICE);  
    }  
      
    @Override  
    public int getCount() {  
        if (mArrayList==null) {  
            return 0;  
        } else {  
            return (mArrayList.size()+1);  
        }  
          
    }  
      
    @Override  
    public Object getItem(int position) {  
        if (mArrayList==null) {  
            return null;  
        } else {  
            if (position>0) {  
                return mArrayList.get(position-1);  
            } else {  
                return mArrayList.get(position+1);  
            }  
        }  
    }  
      
    @Override  
    public long getItemId(int position) {  
        return position;  
    }  
      
    ///////////////////////////////////////////////////////  
    @Override  
    public int getViewTypeCount() {  
        return TYPE_COUNT;  
    }  
      
    @Override  
    public int getItemViewType(int position) {  
        if (position==0) {  
            return FIRST_TYPE;  
        } else {  
            return OTHERS_TYPE;  
        }  
    }  
   ///////////////////////////////////////////////////////  
      
    @Override  
    public View getView(int position, View convertView, ViewGroup parent) {  
        View firstItemView = null;  
        View othersItemView=null;  
        //获取到当前位置所对应的Type  
        currentType= getItemViewType(position);  
        System.out.println("type="+currentType);  
        if (currentType== FIRST_TYPE) {  
            firstItemView = convertView;  
            FirstItemViewHolder firstItemViewHolder=null;  
            if (firstItemView==null) {  
                System.out.println("firstItemView==null ");  
                firstItemView = mLayoutInflater.inflate(R.layout.firstitem,null);  
                firstItemView.setOnClickListener(new OnClickListener() {  
                    @Override  
                    public void onClick(View view) {  
                        System.out.println("=====click first item=======");  
                    }  
                });  
                firstItemViewHolder=new FirstItemViewHolder();  
                firstItemViewHolder.imageView=(ImageView) firstItemView.findViewById(R.id.imageView);  
                firstItemView.setTag(firstItemViewHolder);  
  
            } else {  
                System.out.println("firstItemView!=null ");  
                System.out.println("111 getClass="+firstItemView.getTag().getClass().toString());  
                firstItemViewHolder=(FirstItemViewHolder) firstItemView.getTag();  
            }  
              
            if (firstItemViewHolder.imageView!=null) {  
                firstItemViewHolder.imageView.setImageResource(R.drawable.ic_launcher);  
            }  
              
            convertView=firstItemView;  
  
        } else {  
            othersItemView = convertView;  
            OthersViewHolder othersViewHolder=null;  
            if (othersItemView==null) {  
                System.out.println("othersItemView==null ");  
                othersItemView = mLayoutInflater.inflate(R.layout.othersitem,null);  
                othersViewHolder=new OthersViewHolder();  
                othersViewHolder.textView=(TextView) othersItemView.findViewById(R.id.textView);  
                othersItemView.setTag(othersViewHolder);  
            } else {  
                System.out.println("othersItemView!=null ");  
                System.out.println("222 getClass="+othersItemView.getTag().getClass().toString());  
                othersViewHolder=(OthersViewHolder) othersItemView.getTag();  
            }  
              
            if (mArrayList!=null) {  
                if (othersViewHolder.textView!=null) {  
                    othersViewHolder.textView.setText((String)(mArrayList.get(position-1).get("content")));  
                }  
                  
            }  
              
            convertView=othersItemView;  
  
        }  
  
        return convertView;  
    }  
      
    
    //第一个Item的ViewHolder  
    private class FirstItemViewHolder{  
        ImageView imageView;  
    }  
      
    //除第一个Item以外其余Item的ViewHolder  
    private class OthersViewHolder{
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