Android_拍照功能

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

import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.PixelFormat;
import android.graphics.Bitmap.CompressFormat;
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.Display;
import android.view.KeyEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.Window;
import android.view.WindowManager;
import android.view.SurfaceHolder.Callback;

public class TakePicActivity extends Activity {

    private static final String TAG = "TakePicActivity";

    private SurfaceView surfaceView;

    private Camera camera;

    private boolean preview;

    @Override
    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        Window window = this.getWindow();

        // 设置窗口没有标题
        this.requestWindowFeature(Window.FEATURE_NO_TITLE);

        // 设置窗口全屏显示
        window.setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);

        // 设置窗口高亮
        window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

        setContentView(R.layout.main);

        surfaceView = (SurfaceView) this.findViewById(R.id.surfaceView);

        surfaceView.getHolder().setFixedSize(176, 144);
        surfaceView.getHolder()
                .setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

        surfaceView.getHolder().addCallback(new SurfaceCallBack());
    }

    private final class SurfaceCallBack implements Callback {

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

        }

        @Override
        public void surfaceCreated(SurfaceHolder holder) {

            try {
                camera = Camera.open();

                // 获得窗口管理器
                WindowManager wm = (WindowManager) getSystemService(Context.WINDOW_SERVICE);

                // 获得屏幕
                Display display = wm.getDefaultDisplay();

                // 获得屏幕参数对象
                Parameters parameters = camera.getParameters();

                // 设置预览照片的大小
                parameters.setPreviewSize(display.getWidth(), display
                        .getHeight());

                // 每秒3帧从取景框中获得画片
                parameters.setPreviewFrameRate(3);

                // 设置照片的输出格式
                parameters.setPictureFormat(PixelFormat.JPEG);

                // 设置照片质量
                parameters.set("jpeg-quality", 85);

                // 设置排出来的照片的大小
                parameters.setPictureSize(display.getWidth(), display
                        .getHeight());

                camera.setParameters(parameters);

                // 通过SurfaceView显示取景画面
                camera.setPreviewDisplay(surfaceView.getHolder());

                // 开始预览
                camera.startPreview();

                preview = true;

            } catch (IOException e) {
                Log.e(TAG, e.toString());
            }
        }

        @Override
        public void surfaceDestroyed(SurfaceHolder holder) {

            if (camera != null) {

                if (preview) {
                    camera.stopPreview();
                    preview = false;
                }

                camera.release();
            }
        }

    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {

        // 单击案件
        if (camera != null && event.getRepeatCount() == 0) {

            switch (keyCode) {

            case KeyEvent.KEYCODE_SEARCH:

                // 设置自动对焦
                camera.autoFocus(null);

                break;

            case KeyEvent.KEYCODE_CAMERA:
            case KeyEvent.KEYCODE_DPAD_CENTER:

                camera.takePicture(null, null, new TakePicCallBack());

                break;

            default:
                break;
            }
        }

        //返回true会阻止事件向上传递
        return true;
    }

    private final class TakePicCallBack implements PictureCallback {

        @Override
        public void onPictureTaken(byte[] data, Camera camera) {

            try {
                Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);

                File file = new File(Environment.getExternalStorageDirectory(),
                        System.currentTimeMillis() + ".jpg");

                FileOutputStream fos = new FileOutputStream(file);

                bitmap.compress(CompressFormat.JPEG, 100, fos);
                
                fos.close();
                
                camera.stopPreview();
                camera.startPreview();
                
            } catch (Exception e) {
                Log.e(TAG, e.toString());
            }
        }
    }
}