Android图片缩略图

package com.xzq.thumbnailtest;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.media.ThumbnailUtils;
import android.os.Bundle;
import android.view.Menu;
import android.view.Window;
import android.widget.ImageView;

/**
 * @author XZQ
 * @see http://blog.csdn.net/cmdkmd?viewmode=contents
 */
public class MainActivity extends Activity {

    private Bitmap bitmap;
    private ImageView image;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.main);

        image = (ImageView) findViewById(R.id.image);
        bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.a);
        bitmap = ThumbnailUtils.extractThumbnail(bitmap, 200, 200);
        image.setImageBitmap(bitmap);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }
}

<LinearLayout 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:orientation="vertical" >

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dip"
        android:contentDescription="@string/app_name"
        android:src="@drawable/a" />

    <ImageView
        android:id="@+id/image"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dip"
        android:layout_marginTop="10dip"
        android:contentDescription="@string/app_name" />

</LinearLayout>