21天学习android开发教程之SurfaceView与多线程的混搭

<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"     android:layout_width="fill_parent" android:layout_height="fill_parent"    android:orientation="vertical">    <linearlayout android:id="@+id/LinearLayout01"         android:layout_width="wrap_content" android:layout_height="wrap_content">        <button android:id="@+id/Button01" android:layout_width="wrap_content"             android:layout_height="wrap_content" android:text="单个独立线程">        <button android:id="@+id/Button02" android:layout_width="wrap_content"             android:layout_height="wrap_content" android:text="两个独立线程">        <surfaceview android:id="@+id/SurfaceView01"         android:layout_width="fill_parent" android:layout_height="fill_parent">

package com.testSurfaceView;import java.lang.reflect.Field;import java.util.ArrayList;import android.app.Activity;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.graphics.Paint;import android.graphics.Rect;import android.os.Bundle;import android.util.Log;import android.view.SurfaceHolder;import android.view.SurfaceView;import android.view.View;import android.widget.Button;public class testSurfaceView extends Activity {    /** Called when the activity is first created. */    Button btnSingleThread, btnDoubleThread;    SurfaceView sfv;    SurfaceHolder sfh;    ArrayList imgList = new ArrayList();    int imgWidth, imgHeight;    Bitmap bitmap;//独立线程读取，独立线程绘图    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);        btnSingleThread = (Button) this.findViewById(R.id.Button01);        btnDoubleThread = (Button) this.findViewById(R.id.Button02);        btnSingleThread.setOnClickListener(new ClickEvent());        btnDoubleThread.setOnClickListener(new ClickEvent());        sfv = (SurfaceView) this.findViewById(R.id.SurfaceView01);        sfh = sfv.getHolder();        sfh.addCallback(new MyCallBack());// 自动运行surfaceCreated以及surfaceChanged    }    class ClickEvent implements View.OnClickListener {        @Override        public void onClick(View v) {            if (v == btnSingleThread) {                new Load_DrawImage(0, 0).start();//开一条线程读取并绘图            } else if (v == btnDoubleThread) {                new LoadImage().start();//开一条线程读取                new DrawImage(imgWidth + 10, 0).start();//开一条线程绘图            }        }    }    class MyCallBack implements SurfaceHolder.Callback {        @Override        public void surfaceChanged(SurfaceHolder holder, int format, int width,                int height) {            Log.i("Surface:", "Change");        }        @Override        public void surfaceCreated(SurfaceHolder holder) {            Log.i("Surface:", "Create");            // 用反射机制来获取资源中的图片ID和尺寸            Field[] fields = R.drawable.class.getDeclaredFields();            for (Field field : fields) {                if (!"icon".equals(field.getName()))// 除了icon之外的图片                {                    int index = 0;                    try {                        index = field.getInt(R.drawable.class);                    } catch (IllegalArgumentException e) {                        // TODO Auto-generated catch block                        e.printStackTrace();                    } catch (IllegalAccessException e) {                        // TODO Auto-generated catch block                        e.printStackTrace();                    }                    // 保存图片ID                    imgList.add(index);                }            }            // 取得图像大小            Bitmap bmImg = BitmapFactory.decodeResource(getResources(),                    imgList.get(0));            imgWidth = bmImg.getWidth();            imgHeight = bmImg.getHeight();        }        @Override        public void surfaceDestroyed(SurfaceHolder holder) {            Log.i("Surface:", "Destroy");        }    }    /*     * 读取并显示图片的线程     */    class Load_DrawImage extends Thread {        int x, y;        int imgIndex = 0;        public Load_DrawImage(int x, int y) {            this.x = x;            this.y = y;        }        public void run() {            while (true) {                Canvas c = sfh.lockCanvas(new Rect(this.x, this.y, this.x                        + imgWidth, this.y + imgHeight));                Bitmap bmImg = BitmapFactory.decodeResource(getResources(),                        imgList.get(imgIndex));                c.drawBitmap(bmImg, this.x, this.y, new Paint());                imgIndex++;                if (imgIndex == imgList.size())                    imgIndex = 0;                sfh.unlockCanvasAndPost(c);// 更新屏幕显示内容            }        }    };    /*     * 只负责绘图的线程     */    class DrawImage extends Thread {        int x, y;        public DrawImage(int x, int y) {            this.x = x;            this.y = y;        }        public void run() {            while (true) {                if (bitmap != null) {//如果图像有效                    Canvas c = sfh.lockCanvas(new Rect(this.x, this.y, this.x                            + imgWidth, this.y + imgHeight));                    c.drawBitmap(bitmap, this.x, this.y, new Paint());                    sfh.unlockCanvasAndPost(c);// 更新屏幕显示内容                }            }        }    };    /*     * 只负责读取图片的线程     */    class LoadImage extends Thread {        int imgIndex = 0;        public void run() {            while (true) {                bitmap = BitmapFactory.decodeResource(getResources(),                        imgList.get(imgIndex));                imgIndex++;                if (imgIndex == imgList.size())//如果到尽头则重新读取                    imgIndex = 0;            }        }    };}