androoid中SurfaceView加载照相机功能页面

package com.example.surfaceview;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import android.app.Activity;
import android.hardware.Camera;
import android.hardware.Camera.Parameters;
import android.hardware.Camera.PictureCallback;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.SurfaceHolder;
import android.view.SurfaceHolder.Callback;
import android.view.SurfaceView;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;

/**
 * 
 * 使用SurfaceView加载照相机功能页面
 * @author 浅议爱
 *
 */
public class MainActivity extends Activity {

    //定义控件
    private SurfaceView mSurfaceView;
    private Camera camera;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

//      requestWindowFeature(Window.FEATURE_NO_TITLE); // 没有标题  必须在设置布局之前找到调用
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, // 设置全屏显示
        WindowManager.LayoutParams.FLAG_FULLSCREEN);

        mSurfaceView=(SurfaceView) findViewById(R.id.mysurfaceview);
        SurfaceHolder holder = mSurfaceView.getHolder();
        holder.setFixedSize(176, 155);// 设置分辨率 
        holder.setKeepScreenOn(true);
        holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

        // SurfaceView只有当activity显示到了前台，该控件才会被创建     因此需要监听surfaceview的创建
          holder.addCallback(new MySurfaceCallback());

    }

     /**
       * 监听surfaceview的创建
       * @author Administrator
       * Surfaceview只有当activity显示到前台，该空间才会被创建
       */

    private final class MySurfaceCallback implements Callback{

        @Override
        public void surfaceCreated(SurfaceHolder holder) {
            // TODO Auto-generated method stub
              // 当surfaceview创建就去打开相机
            try {
                camera = Camera.open();
                Parameters params = camera.getParameters();
                 Log.i("i", params.flatten());
                 params.setJpegQuality(80);  // 设置照片的质量
                 params.setPictureSize(1024, 768);
                 params.setPreviewFrameRate(5);  // 预览帧率
                 camera.setParameters(params); // 将参数设置给相机
                 // 设置预览显示
                 camera.setPreviewDisplay(mSurfaceView.getHolder());
                 // 开启预览
                 camera.startPreview();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }


        }
       //改变时，，，不用执行任何操作
        @Override
        public void surfaceChanged(SurfaceHolder holder, int format, int width,
                int height) {
            // TODO Auto-generated method stub

        }

        @Override
        public void surfaceDestroyed(SurfaceHolder holder) {
            // TODO Auto-generated method stub
               if(camera != null){
                      camera.release();
                      camera = null;
                     }
        }

        public void autofoucs(View v){
         // 自动对焦由硬件来完成
          }

        /*
         * shutter:快门被按下
         * raw:相机所捕获的原始数据
         * jpeg:相机处理的数据
         */   
        public void takepicture(View v){
         camera.takePicture(null, null, new MyPictureCallback());

         }

        //相机拍摄
        private final  class MyPictureCallback implements PictureCallback{

            @Override
            public void onPictureTaken(byte[] data, Camera camera) {
                // TODO Auto-generated method stub
            //将拍的照片保存到sd卡
             try {
                File file = new File(Environment.getExternalStorageDirectory(),System.currentTimeMillis()+".jpg");
                 FileOutputStream fos = new FileOutputStream(file);
                 fos.write(data);
                 // 在拍照的时候相机是被占用的,拍照之后需要重新预览
                  camera.startPreview();
            } catch (Exception e) {
                // TODO Auto-generated catch block
            }
            }

        }
    }
}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="wrap_content"
    android:layout_height="match_parent"
    tools:context="com.example.surfaceview.MainActivity" >

    <SurfaceView
        android:id="@+id/mysurfaceview"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.surfaceview"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="14"
        android:targetSdkVersion="14" />
    <!--  sd创建和删除文件权限-->
    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>
    <!-- 使用照相机权限 -->
    <uses-permission android:name="android.permission.CAMERA"/>
    <!-- 写入sd卡权限 -->
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity 
            android:screenOrientation="landscape"
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>