GridView单选效果 点击选中一项时，再点击选中另一项时改变背景，原来选中的项取消换回原来的背景

/**
*xml Item部分
*/

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
tools:context=".MainActivity" >

<ImageView
android:id="@+id/imageview"
android:padding="10dip"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center"
android:src="@drawable/icon_checkbox_normal"
android:clickable="true"/>

</RelativeLayout>

/**
*xml部分
*/
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_horizontal"
tools:context=".MainActivity" >

<GridView android:id="@+id/gridview_radio"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:numColumns="4"
android:padding="10dp"
android:horizontalSpacing="4dp"
android:verticalSpacing="4dp"
android:gravity="center"/>

</RelativeLayout>

/**
*java部分
*/
public class MainActivity extends Activity {

private int icon[] = { R.drawable.icon_checkbox_normal,
R.drawable.icon_checkbox_normal, R.drawable.icon_checkbox_normal,
R.drawable.icon_checkbox_normal, R.drawable.icon_checkbox_normal,
R.drawable.icon_checkbox_normal, R.drawable.icon_checkbox_normal,
R.drawable.icon_checkbox_normal };

MyAdapter myAdapter;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

// 定义Adapter,不用每次new
myAdapter = new MyAdapter();

GridView gridview_radio = (GridView) findViewById(R.id.gridview_radio);
gridview_radio.setAdapter(myAdapter);

gridview_radio.setOnItemClickListener(new OnItemClickListener() {

@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// TODO Auto-generated method stub
myAdapter.setSeclection(position);
myAdapter.notifyDataSetChanged();
}
});
}

class MyAdapter extends BaseAdapter {
private int clickTemp = -1;

// 标识选择的Item
public void setSeclection(int position) {
clickTemp = position;
}

@Override
public int getCount() {
// TODO Auto-generated method stub
return icon.length;
}

@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return icon[position];
}

@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {

// Holder 是设计个静态类，缓存一下，避免Listview更新的时候，重新操作。
Holder holder = null;
if (convertView == null) {
holder = new Holder();
convertView = View.inflate(MainActivity.this,
R.layout.activity_main_item, null);

holder.imageView = (ImageView) convertView
.findViewById(R.id.imageview);

convertView.setTag(holder);
} else {
holder = (Holder) convertView.getTag();
}

if (clickTemp == position) {
holder.imageView
.setImageResource(R.drawable.icon_checkbox_checked);
} else {
holder.imageView
.setImageResource(R.drawable.icon_checkbox_normal);
}
return convertView;
}

}

static class Holder {
ImageView imageView;
}
}