SurfaceView與多線程

SurfaceView與多線程

爲了實現數據加載和在SurfaceView上畫圖分離，採取線程分離，把數據加載放在一個線程中，把畫圖放在另外一個線程中。採用多線程的生產者和消費者模式，設置一箇中間類，即圖像處理類實現資源中的數據編碼成Bitmap類數據以及把Bitmap類數據畫在Surface上。同時採用模塊同步，實現線程的等待和喚醒。這樣畫圖的速度較使用標誌位，而不採取線程的等到與喚醒要快。

主程序：

package com.example.surfaceviewtest1;
 
import java.lang.reflect.Field;
import java.util.ArrayList;
 
 
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
 
 
public class Activity02 extends Activity {
      
       private Button threadButton;
       private SurfaceView surfaceView;
       private SurfaceHolder surfaceHolder;
       private ArrayList<Integer> imageList = new ArrayList<Integer>();
       private ImageResource imageResource;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_activity02);
        //獲得控件的引用
        threadButton = (Button)findViewById(R.id.threadButton);
        surfaceView = (SurfaceView)findViewById(R.id.surfaceView1);
        //通過surfaceView對象獲得surfaceHolder對象
        surfaceHolder = surfaceView.getHolder();
        //給surfaceHolder添加回調函數
        surfaceHolder.addCallback(new MyCallback());
        threadButton.setOnClickListener(new ButtonListener());
    }
 
    class ButtonListener implements OnClickListener{
 
              @Override
              public void onClick(View v) {
                     // TODO Auto-generated method stub
                     imageResource = new ImageResource(Activity02.this, imageList, surfaceHolder);
                     new Thread(new LoadImage(imageResource)).start();
                     new Thread(new DrawImage(imageResource)).start();
                    
              }
         
    }
   
    /**
     *MyCallback類用來實現對Surface狀態的變化的處理
     * @author denglinyi
     *
     */
    class MyCallback implements SurfaceHolder.Callback{
 
              @Override
              public void surfaceChanged(SurfaceHolder holder, int format, int width,
                            int height) {
                     // TODO Auto-generated method stub
                    
              }
 
              @Override
              public void surfaceCreated(SurfaceHolder holder) {
                     // TODO Auto-generated method stub
                     int index = 0;
                     //利用反射機制獲取圖像的ID和大小
                     Field[] fields = R.drawable.class.getDeclaredFields();
                     for (Field field : fields) {
                            if (!"ic_action_search".equals(field.getName()) && !"ic_launcher".equals(field.getName())) {
                                   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();
                                   }
                                   imageList.add(index);
                            }
                     }
              }
 
              @Override
              public void surfaceDestroyed(SurfaceHolder holder) {
                     // TODO Auto-generated method stub
                    
              }
         
    }
   
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_activity02, menu);
        return true;
    }
 
   
}

圖像處理程序：
package com.example.surfaceviewtest1;
 
import java.util.ArrayList;
 
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.view.SurfaceHolder;
 
public class ImageResource {
      
       private Context context;
       private Bitmap image;
       private boolean flag=true;
       private ArrayList<Integer> imageList;
       private int size=0;
       private int index=0;
       private SurfaceHolder surfaceHolder;
       public ImageResource(Context context, ArrayList<Integer> imageList,SurfaceHolder surfaceHolder) {
              this.context = context;
              this.imageList = imageList;
              this.surfaceHolder = surfaceHolder;
              size = imageList.size();
       }
      
       public void loadImage() {
              synchronized (this) {
                     if (!flag) {
                            try {
                                   this.wait();
                            } catch (InterruptedException e) {
                                   // TODO Auto-generated catch block
                                   e.printStackTrace();
                            }
                     }
                     if (flag) {
                            image = BitmapFactory.decodeResource(context.getResources(), imageList.get(index));
                            System.out.println("loadImage--->" + System.currentTimeMillis());
                            System.out.println("index---->" + imageList.get(index));
                            index++;
                            if (index >= size) {
                                   index = 0;
                            }
                            flag = false;
                            this.notify();
                            System.out.println("loadImage---->");
                     }
              }
             
       }
      
       public void drawImage() {
              synchronized (this) {
                     if (flag) {
                            try {
                                   this.wait();
                            } catch (InterruptedException e) {
                                   // TODO Auto-generated catch block
                                   e.printStackTrace();
                            }
                     }
                     if (!flag) {
                            Canvas canvas = surfaceHolder.lockCanvas(new Rect(0, 0, 500, 500));
                            canvas.drawBitmap(image, 0, 0, null);
                            surfaceHolder.unlockCanvasAndPost(canvas);
                            flag = false;
                            System.out.println("drawImage--->" + System.currentTimeMillis());
                            flag = true;
                            this.notify();
                            System.out.println("drawImage---->");
                     }
              }
             
       }
}
 
數據加載線程：
package com.example.surfaceviewtest1;
 
publicclass LoadImageimplements Runnable {
    private ImageResourceimageResource;
    public LoadImage(ImageResource imageResource) {
       //TODO Auto-generated constructor stub
       this.imageResource = imageResource;
    }
    @Override
    publicvoid run() {
       //TODO Auto-generated method stub
       while (true) {
           imageResource.loadImage();
       }  
    }
 
}
畫圖線程：
package com.example.surfaceviewtest1;
 
publicclass DrawImageimplements Runnable {
    private ImageResourceimageResource;
   
    public DrawImage(ImageResource imageResource) {
       //TODO Auto-generated constructor stub
       this.imageResource = imageResource;
    }
    @Override
    publicvoid run() {
       //TODO Auto-generated method stub
       while (true) {
           imageResource.drawImage();
        }
    }
 
}