继承SurfaceView实现图片自动播放

package com.farben.ams.widget;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.util.List;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.Paint.Style;
import android.media.ThumbnailUtils;
import android.provider.MediaStore.Images.Thumbnails;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.ViewGroup.LayoutParams;

/**
* 图片浏览器
* @author Keynes Cao
* @create 2011-12-5 上午9:24:23
* @package com.farben.ams.widget
*/
public class ImageSurfaceView  extends SurfaceView implements SurfaceHolder.Callback,Runnable{

//图片集
private List<String>         mList            =    null;
//运行状态
public     boolean             mLoop             =     false;
//获取画布
private SurfaceHolder         mSurfaceHolder     =     null;
//图片索引
private int                 mCount             =     0;
//时间间隔
private long                 speed             =     1000;

private static Matrix         matrix             =     new Matrix();
/**
* @param context
* <see>容器</see>
* @param list
* <see>图片地址列表 </see>
* @param rate
* <see>图片切换时间　单位:毫秒</see>
*
*/
public ImageSurfaceView(Context context,List<String>list,long speed) {
super(context);
if(list!=null && list.size()>0){
this.mList = list;
this.speed = speed;
}
mSurfaceHolder = getHolder();
mSurfaceHolder.addCallback(this);
mLoop = true;//开始画图
}

public void surfaceChanged(SurfaceHolder holder, int format, int width,    int height) {}
//图像创建时
public void surfaceCreated(SurfaceHolder holder) {
if(mList!=null && mList.size()>0){
if(mList.size() == 1){
Log.d("ImageSurfaceView"," Only one picture");
drawImg();
}else{
Log.d("ImageSurfaceView"," run Thread.");
new Thread(this).start();
}
}

}
//视图销毁时
public void surfaceDestroyed(SurfaceHolder holder) {
mLoop = false;
}
//画图方法
private void drawImg(){
Canvas canvas = mSurfaceHolder.lockCanvas();
if(canvas == null || mSurfaceHolder == null){
return;
}
if(mCount >= mList.size()){
mCount = 0;
}
Bitmap bitmap  = null;
try{
String path = mList.get(mCount++);
bitmap  = BitmapFactory.decodeStream(new FileInputStream(path));
if(bitmap!=null){
//画布宽和高
int height = getHeight();
int width  = getWidth();
//生成合适的图像
bitmap = getReduceBitmap(bitmap,width,height);

Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setStyle(Style.FILL);
//清屏
paint.setColor(Color.BLACK);
canvas.drawRect(new Rect(0, 0, getWidth(),getHeight()), paint);
//Log.d("ImageSurfaceView_IMG",path);
//画图
canvas.drawBitmap(bitmap, matrix, paint);
}
//解锁显示
mSurfaceHolder.unlockCanvasAndPost(canvas);
}catch(Exception ex){
Log.e("ImageSurfaceView",ex.getMessage());
return;
}finally{
//资源回收
if(bitmap!=null){
bitmap.recycle();
}
}
}
//刷新图片
public void run() {
while(mLoop){
synchronized (mSurfaceHolder) {
drawImg();
}
try {
Thread.sleep(speed);
} catch (InterruptedException e) {
Log.e("ImageSurfaceView_Thread",e.getMessage());
}
}
mList = null;//消毁
}
//缩放图片
private Bitmap getReduceBitmap(Bitmap bitmap ,int w,int h){
int     width     =     bitmap.getWidth();
int     hight     =     bitmap.getHeight();
Matrix     matrix     =     new Matrix();
float     wScake     =     ((float)w/width);
float     hScake     =     ((float)h/hight);
matrix.postScale(wScake, hScake);
return Bitmap.createBitmap(bitmap, 0,0,width,hight,matrix,true);
}

}