使用手机的摄像头进行拍照

package cn.itcast.camera;

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

import android.app.Activity;
import android.graphics.PixelFormat;
import android.hardware.Camera;
import android.os.Bundle;
import android.os.Environment;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.Toast;

public class DemoActivity extends Activity implements OnClickListener {
	private SurfaceView sv;
	private Button bt_take_pic, bt_auto_focus;
	private SurfaceHolder holder;
	private 		Camera camera ;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //隐藏掉activity的标题栏 
        // 必须写到setcontentview之前 
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        //实现窗体的全屏显示
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.main);
        sv = (SurfaceView) this.findViewById(R.id.sv);
        bt_take_pic = (Button) this.findViewById(R.id.bt_take_pic);
        bt_auto_focus = (Button) this.findViewById(R.id.bt_auto_focus); 
        bt_take_pic.setOnClickListener(this);
        bt_auto_focus.setOnClickListener(this);
		//得到holder
        holder =   sv.getHolder();
		//设置类型
        holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
		//设置事件  create change destory
        holder.addCallback(new MyHolderCallback());
        
    }

	public void onClick(View v) {
		switch (v.getId()) {
		case R.id.bt_auto_focus:
			//自动对焦
			camera.autoFocus(null);
			break;

		case R.id.bt_take_pic:
			//拍照 
			//ShutterCallback 
			// raw 未经过处理的意思  设置的事件是onPictureTaken事件
			camera.takePicture(null, null, new MyPicCallback());
			break;
		}
		
	}
	private class MyPicCallback implements Camera.PictureCallback{

		public void onPictureTaken(byte[] data, Camera camera) {
			if(Environment.MEDIA_MOUNTED.equals( Environment.getExternalStorageState())){
				try {
					File file = new File(Environment.getExternalStorageDirectory(),System.currentTimeMillis()+".jpg");
					FileOutputStream fos = new FileOutputStream(file);
					//得到输出流流   将数据写入文件中
					fos.write(data);
					fos.flush();
					fos.close();
					
				} catch (Exception e) {
					Toast.makeText(getApplicationContext(), "保存照片失败", 0).show();
					e.printStackTrace();
				}finally{
					camera.startPreview();
				}
			}else{
				Toast.makeText(getApplicationContext(), "sd卡不可用", 0).show();
			}
		}
	}
	
	
	private class MyHolderCallback implements SurfaceHolder.Callback{

		public void surfaceCreated(SurfaceHolder holder) {
			System.out.println("holder 被创建 ");
			DemoActivity.this.holder = holder;
			//得到camara   调用底层的c语言代码,在某个事件内只能被一个应用使用,
			camera = Camera.open();
			// 要想给照相机设置参数 必须要知道你的相机支持什么样子的参数 
			//System.out.println(camera.getParameters().flatten());
			Camera.Parameters parms = camera.getParameters();
			//每秒显示多少帧
			parms.setPreviewFrameRate(5);
			parms.setPictureSize(1280, 960);
			parms.setPictureFormat(PixelFormat.JPEG);//设置照片的输出格式
			parms.set("jpeg-quality", 85);//照片质量

			camera.setParameters(parms);
			try {
			//设置完参数后,给camara设置内容holder
				camera.setPreviewDisplay(holder);
			} catch (IOException e) {
				e.printStackTrace();
			}//通过SurfaceView显示取景画面
			camera.startPreview();//开始预览


		}

		public void surfaceChanged(SurfaceHolder holder, int format, int width,
				int height) {
		}

		public void surfaceDestroyed(SurfaceHolder holder) {
			System.out.println("holder被销毁");
			camera.release();
			camera = null;

		}
		
	}
}