GridView

GridView

点击GridView中的某项时，只回调了onItemSelected，而没有回调onItemClick，Why????
main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android=""
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <ImageView
        android:id="@+id/imageView"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_launcher"
        />
    <GridView
        android:id="@+id/gridView"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:horizontalSpacing="20dp"
        android:numColumns="1"
        android:padding="20dp"
        android:verticalSpacing="20dp" />

</LinearLayout>

cell.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android=""
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    <ImageView
        android:id="@+id/imageViewValue"
        android:layout_width="48dp"
        android:layout_height="48dp"
       />
</LinearLayout>

package com.lwb.gridview;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import com.example.android_gridview.R;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.SimpleAdapter;

public class MainActivity extends Activity implements OnItemSelectedListener,
OnItemClickListener{

    private ImageView imageView = null;
    private GridView gridView = null;
    private int[] resIds = new int[]{
            R.drawable.item1,R.drawable.item3,R.drawable.item4,
            R.drawable.item5,R.drawable.item6,R.drawable.item7,R.drawable.item8,
            R.drawable.item9,R.drawable.item10,R.drawable.item11,R.drawable.item12,
            R.drawable.item13
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);

        setContentView(R.layout.main);
        gridView = (GridView)this.findViewById(R.id.gridView);

        List<Map<String,Object>> list = new ArrayList<Map<String,Object>>();
        for(int i=0;i<resIds.length;i++){
            Map<String,Object> cell = new HashMap<String,Object>();
            cell.put("imageViewKey", resIds[i]);
            list.add(cell);
        }


        SimpleAdapter simpleAdapter = new SimpleAdapter(MainActivity.this, list,R.layout.cell, new String[]{"imageViewKey"}, new int[]{R.id.imageViewValue});
//        SimpleAdapter simpleAdapter2= new SimpleAdapter(context, data, resource, from, to)

        gridView.setAdapter(simpleAdapter);

        imageView= (ImageView)this.findViewById(R.id.imageView );
        gridView.setOnItemClickListener(this);
        gridView.setOnItemSelectedListener(this);
        imageView.setImageResource(resIds[0]);
    }

    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position,
            long id) {
        // TODO Auto-generated method stub
        imageView.setImageResource(resIds[position]);
        System.out.println("onItemSelected" + position);
    }

    @Override
    public void onNothingSelected(AdapterView<?> parent) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        // TODO Auto-generated method stub
        imageView.setImageResource(resIds[position]);
        System.out.println("onItemSelected" + position);
    }

}