请教：Matrix 的缩放（Bitmap）

package com.Feier.android.Matrix;



import android.content.Context;

import android.graphics.Bitmap;

import android.graphics.Canvas;

import android.graphics.Matrix;

import android.graphics.drawable.BitmapDrawable;

import android.view.KeyEvent;

import android.view.View;



public class GameView extends View implements Runnable{

	

	private Bitmap mBitmapQQ=null;

	int mBitmapQQ_Width=0;

	int mBitmapQQ_Height=0;

	float Angle=0.0f;

	Matrix mMatrix=new Matrix();

	

	public GameView(Context context){

		super(context);

		//装载资源

		mBitmapQQ=((BitmapDrawable)getResources().getDrawable(R.drawable.button1)).getBitmap();

		mBitmapQQ_Width=mBitmapQQ.getWidth();

		mBitmapQQ_Height=mBitmapQQ.getHeight();

		

		new Thread(this).start();

	}

	

	public void onDraw(Canvas canvas){

		super.onDraw(canvas);

		

		//重置mMatrix

		mMatrix.reset();

		//设置旋转

		mMatrix.setRotate(Angle);

		//按mMatrix的旋转构建新的Bitmap

		Bitmap mBitmapQQ2=Bitmap.createBitmap(mBitmapQQ,0,0,mBitmapQQ_Width,mBitmapQQ_Height,mMatrix,true);

		//绘制旋转之后的图像

		GameView.drawImage(canvas,mBitmapQQ2,(320-mBitmapQQ_Width)/2,10);

		

		mBitmapQQ2=null;

	}

	

	public boolean onKeyDown(int keyCode,KeyEvent event){

		if (keyCode==KeyEvent.KEYCODE_DPAD_LEFT){

			Angle--;

		}

		else if(keyCode==KeyEvent.KEYCODE_DPAD_RIGHT){

			Angle++;

		}

		return true;

	}

	

	public void run(){

		while(!Thread.currentThread().isInterrupted()){

			try{

				Thread.sleep(100);

			}

			catch(Exception e){

				Thread.currentThread().interrupt();

			}

			postInvalidate();

		}

	}

	

	/**

	 * 绘制一个Bitmap

	 * @param canvas画布

	 * @param btimap画布

	 * @param x 屏幕上的x坐标

	 * @param y 屏幕上的y坐标

	 */

	public static void drawImage(Canvas canvas, Bitmap bitmap,int x,int y){

		canvas.drawBitmap(bitmap, x,y,null);

	}

}

package com.Feier.android.Matrix;



import android.app.Activity;

import android.os.Bundle;



public class Activity01 extends Activity {

	

	private GameView mGameView;

    /** Called when the activity is first created. */

    @Override

    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        

        mGameView=new GameView(this);

        setContentView(mGameView);

        //setContentView(R.layout.main);

    }

}