SurfaceView之拍照

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。

  // 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());

在拍照的时候相机是被占用的，拍照之后需要重新开启预览。

 

具体拍照的demo：

package com.android.hzy.takepicture;

import java.io.File;
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.SurfaceHolder;
import android.view.SurfaceHolder.Callback;
import android.view.SurfaceView;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;

public class MainActivity extends Activity {
    
    private SurfaceView surfaceview;
    private Camera camera;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE); // 没有标题  必须在设置布局之前找到调用
        setContentView(R.layout.activity_main);
        
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, // 设置全屏显示
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        
        surfaceview = (SurfaceView) findViewById(R.id.surfaceview);
        SurfaceHolder holder = surfaceview.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 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

            try {
                // 当surfaceview创建就去打开相机
                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(surfaceview.getHolder());
                // 开启预览
                camera.startPreview();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            
        }

        @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
    }
    
    public void takepicture(View v){
        /*
         * 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
         */
        camera.takePicture(null, null, new MyPictureCallback());
    }
    
    private final class MyPictureCallback implements PictureCallback{

        @Override
        public void onPictureTaken(byte[] data, Camera camera) {
            // TODO Auto-generated method stub
            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
                e.printStackTrace();
            }
            
        }
        
    }

}