android中RSSurfaceView

RSSurfaceView直接繼承自SurfaceView,實現了SurfaceHolder.Callback回調接口。解析如下：

1、 構造方法1

 public RSSurfaceView(Context context) {
        super(context);
        init();
        //Log.v(RenderScript.LOG_TAG, "RSSurfaceView");
    }

2、構造方法2

    public RSSurfaceView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
        //Log.v(RenderScript.LOG_TAG, "RSSurfaceView");
    }

3、初始化：增加回調，以便當surface被創建和摧毀時能收到通知。

    private void init() {
        // Install a SurfaceHolder.Callback so we get notified when the
        // underlying surface is created and destroyed
        SurfaceHolder holder = getHolder();
        holder.addCallback(this);
    }

4、創建時的回調

 public void surfaceCreated(SurfaceHolder holder) {
        mSurfaceHolder = holder;
    }

5、摧毀時的回調

    public void surfaceDestroyed(SurfaceHolder holder) {
        synchronized (this) {
            // Surface will be destroyed when we return
            if (mRS != null) {
                mRS.setSurface(null, 0, 0);
            }
        }
    }

6、改變時的回調

    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        synchronized (this) {
            if (mRS != null) {
                mRS.setSurface(holder, w, h);
            }
        }
    }

7、暫停：通知該View當前activity已經暫停了，當activity被暫停時必須調用改方法，調用此方法將暫停渲染線程，必須在渲染器設置之後才能調用。

  public void pause() {
        if(mRS != null) {
            mRS.pause();
        }
    }

8、恢復：通知此View當前activity已經恢復了，當activity恢復時必須調用此方法去重新創建OpenGL展示，和恢復渲染線程；必須在渲染器設置之後才能調用。

  public void resume() {
        if(mRS != null) {
            mRS.resume();
        }
    }

9、創建RenderScriptGL

 public RenderScriptGL createRenderScriptGL(RenderScriptGL.SurfaceConfig sc) {
      RenderScriptGL rs = new RenderScriptGL(this.getContext(), sc);
        setRenderScriptGL(rs);
        return rs;
    }

10、摧毀當前的RenderScriptGL

  public void destroyRenderScriptGL() {
        synchronized (this) {
            mRS.destroy();
            mRS = null;
        }
    }

11、設置RenderScriptGL

 public void setRenderScriptGL(RenderScriptGL rs) {
        mRS = rs;
    }

12、獲取當前RenderScriptGL

    public RenderScriptGL getRenderScriptGL() {
        return mRS;
    }

附上源碼：

package android.renderscript;

import java.io.Writer;
import java.util.ArrayList;
import java.util.concurrent.Semaphore;

import android.content.Context;
import android.os.Handler;
import android.os.Message;
import android.util.AttributeSet;
import android.util.Log;
import android.view.Surface;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

/**
 * @deprecated in API 16
 * The Surface View for a graphics renderscript (RenderScriptGL) to draw on.
 *
 * 
 * 
Developer Guides
 * 
For more information about creating an application that uses Renderscript, read the
 * Renderscript developer guide.
 * 
 */
public class RSSurfaceView extends SurfaceView implements SurfaceHolder.Callback {
    private SurfaceHolder mSurfaceHolder;
    private RenderScriptGL mRS;

    /**
     * @deprecated in API 16
     * Standard View constructor. In order to render something, you
     * must call {@link android.opengl.GLSurfaceView#setRenderer} to
     * register a renderer.
     */
    public RSSurfaceView(Context context) {
        super(context);
        init();
        //Log.v(RenderScript.LOG_TAG, "RSSurfaceView");
    }

    /**
     * @deprecated in API 16
     * Standard View constructor. In order to render something, you
     * must call {@link android.opengl.GLSurfaceView#setRenderer} to
     * register a renderer.
     */
    public RSSurfaceView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
        //Log.v(RenderScript.LOG_TAG, "RSSurfaceView");
    }

    private void init() {
        // Install a SurfaceHolder.Callback so we get notified when the
        // underlying surface is created and destroyed
        SurfaceHolder holder = getHolder();
        holder.addCallback(this);
    }

    /**
     * @deprecated in API 16
     * This method is part of the SurfaceHolder.Callback interface, and is
     * not normally called or subclassed by clients of RSSurfaceView.
     */
    public void surfaceCreated(SurfaceHolder holder) {
        mSurfaceHolder = holder;
    }

    /**
     * @deprecated in API 16
     * This method is part of the SurfaceHolder.Callback interface, and is
     * not normally called or subclassed by clients of RSSurfaceView.
     */
    public void surfaceDestroyed(SurfaceHolder holder) {
        synchronized (this) {
            // Surface will be destroyed when we return
            if (mRS != null) {
                mRS.setSurface(null, 0, 0);
            }
        }
    }

    /**
     * @deprecated in API 16
     * This method is part of the SurfaceHolder.Callback interface, and is
     * not normally called or subclassed by clients of RSSurfaceView.
     */
    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        synchronized (this) {
            if (mRS != null) {
                mRS.setSurface(holder, w, h);
            }
        }
    }

   /**
     * @deprecated in API 16
     * Inform the view that the activity is paused. The owner of this view must
     * call this method when the activity is paused. Calling this method will
     * pause the rendering thread.
     * Must not be called before a renderer has been set.
     */
    public void pause() {
        if(mRS != null) {
            mRS.pause();
        }
    }

    /**
     * @deprecated in API 16
     * Inform the view that the activity is resumed. The owner of this view must
     * call this method when the activity is resumed. Calling this method will
     * recreate the OpenGL display and resume the rendering
     * thread.
     * Must not be called before a renderer has been set.
     */
    public void resume() {
        if(mRS != null) {
            mRS.resume();
        }
    }

    /**
     * @deprecated in API 16
     **/
    public RenderScriptGL createRenderScriptGL(RenderScriptGL.SurfaceConfig sc) {
      RenderScriptGL rs = new RenderScriptGL(this.getContext(), sc);
        setRenderScriptGL(rs);
        return rs;
    }

    /**
     * @deprecated in API 16
     **/
    public void destroyRenderScriptGL() {
        synchronized (this) {
            mRS.destroy();
            mRS = null;
        }
    }

    /**
     * @deprecated in API 16
     **/
    public void setRenderScriptGL(RenderScriptGL rs) {
        mRS = rs;
    }

    /**
     * @deprecated in API 16
     **/
    public RenderScriptGL getRenderScriptGL() {
        return mRS;
    }
}