ZXing 二维码应用

1、导入zxing代码和包

2、下面的类是解析二维码的主要类。

package com.gaint.nebula.interaction.ui.zxing;

import java.io.IOException;
import java.util.Vector;

import android.app.Activity;
import android.content.Intent;
import android.content.res.AssetFileDescriptor;
import android.graphics.Bitmap;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnCompletionListener;
import android.os.Bundle;
import android.os.Handler;
import android.os.Vibrator;
import android.view.SurfaceHolder;
import android.view.SurfaceHolder.Callback;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;

import com.gaint.nebula.interaction.R;
import com.gaint.nebula.interaction.ui.BaseActivity;
import com.google.zxing.BarcodeFormat;
import com.google.zxing.Result;
import com.mining.app.zxing.camera.CameraManager;
import com.mining.app.zxing.decoding.CaptureActivityHandler;
import com.mining.app.zxing.decoding.InactivityTimer;
import com.mining.app.zxing.view.ViewfinderView;
/**
 * Initial the camera
 * @author Ryan.Tang
 */
public class MipcaActivityCapture extends BaseActivity implements Callback {

	private CaptureActivityHandler handler;
	private ViewfinderView viewfinderView;
	private boolean hasSurface;
	private Vector<BarcodeFormat> decodeFormats;
	private String characterSet;
	private InactivityTimer inactivityTimer;
	private MediaPlayer mediaPlayer;
	private boolean playBeep;
	private static final float BEEP_VOLUME = 0.10f;
	private boolean vibrate;

	/** Called when the activity is first created. */
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_capture);
		//ViewUtil.addTopView(getApplicationContext(), this, R.string.scan_card);
		CameraManager.init(getApplication());
		viewfinderView = (ViewfinderView) findViewById(R.id.viewfinder_view);
		
		Button mButtonBack = (Button) findViewById(R.id.button_back);
		mButtonBack.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				MipcaActivityCapture.this.finish();
				
			}
		});
		hasSurface = false;
		inactivityTimer = new InactivityTimer(this);
	}

	@Override
	protected void onResume() {
		super.onResume();
		SurfaceView surfaceView = (SurfaceView) findViewById(R.id.preview_view);
		SurfaceHolder surfaceHolder = surfaceView.getHolder();
		if (hasSurface) {
			initCamera(surfaceHolder);
		} else {
			surfaceHolder.addCallback(this);
			surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
		}
		decodeFormats = null;
		characterSet = null;

		playBeep = true;
		AudioManager audioService = (AudioManager) getSystemService(AUDIO_SERVICE);
		if (audioService.getRingerMode() != AudioManager.RINGER_MODE_NORMAL) {
			playBeep = false;
		}
		initBeepSound();
		vibrate = true;
		
	}

	@Override
	protected void onPause() {
		super.onPause();
		if (handler != null) {
			handler.quitSynchronously();
			handler = null;
		}
		CameraManager.get().closeDriver();
	}

	@Override
	protected void onDestroy() {
		inactivityTimer.shutdown();
		super.onDestroy();
	}
	
	/**
	 * ?????????
	 * @param result
	 * @param barcode
	 */
	public void handleDecode(Result result, Bitmap barcode) {
		inactivityTimer.onActivity();
		playBeepSoundAndVibrate();
		String resultString = result.getText();
		if (resultString.equals("")) {
			Toast.makeText(MipcaActivityCapture.this, "Scan failed!", Toast.LENGTH_SHORT).show();
		}else {
			Intent resultIntent = new Intent();
			Bundle bundle = new Bundle();
			bundle.putString("result", resultString);
			bundle.putParcelable("bitmap", barcode);
			resultIntent.putExtras(bundle);
			this.setResult(RESULT_OK, resultIntent);
		}
		MipcaActivityCapture.this.finish();
	}
	
	private void initCamera(SurfaceHolder surfaceHolder) {
		try {
			CameraManager.get().openDriver(surfaceHolder);
		} catch (IOException ioe) {
			return;
		} catch (RuntimeException e) {
			return;
		}
		if (handler == null) {
			handler = new CaptureActivityHandler(this, decodeFormats,
					characterSet);
		}
	}

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

	}

	@Override
	public void surfaceCreated(SurfaceHolder holder) {
		if (!hasSurface) {
			hasSurface = true;
			initCamera(holder);
		}

	}

	@Override
	public void surfaceDestroyed(SurfaceHolder holder) {
		hasSurface = false;

	}

	public ViewfinderView getViewfinderView() {
		return viewfinderView;
	}

	public Handler getHandler() {
		return handler;
	}

	public void drawViewfinder() {
		viewfinderView.drawViewfinder();

	}

	private void initBeepSound() {
		if (playBeep && mediaPlayer == null) {
			// The volume on STREAM_SYSTEM is not adjustable, and users found it
			// too loud,
			// so we now play on the music stream.
			setVolumeControlStream(AudioManager.STREAM_MUSIC);
			mediaPlayer = new MediaPlayer();
			mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
			mediaPlayer.setOnCompletionListener(beepListener);

			AssetFileDescriptor file = getResources().openRawResourceFd(
					R.raw.beep);
			try {
				mediaPlayer.setDataSource(file.getFileDescriptor(),
						file.getStartOffset(), file.getLength());
				file.close();
				mediaPlayer.setVolume(BEEP_VOLUME, BEEP_VOLUME);
				mediaPlayer.prepare();
			} catch (IOException e) {
				mediaPlayer = null;
			}
		}
	}

	private static final long VIBRATE_DURATION = 200L;

	private void playBeepSoundAndVibrate() {
		if (playBeep && mediaPlayer != null) {
			mediaPlayer.start();
		}
		if (vibrate) {
			Vibrator vibrator = (Vibrator) getSystemService(VIBRATOR_SERVICE);
			vibrator.vibrate(VIBRATE_DURATION);
		}
	}

	/**
	 * When the beep has finished playing, rewind to queue up another one.
	 */
	private final OnCompletionListener beepListener = new OnCompletionListener() {
		public void onCompletion(MediaPlayer mediaPlayer) {
			mediaPlayer.seekTo(0);
		}
	};

}

Intent intent = new Intent();
intent.setClass(BaseActivity.this, MipcaActivityCapture.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivityForResult(intent, SCANNIN_GREQUEST_CODE);

 @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    	if (requestCode == SCANNIN_GREQUEST_CODE) {
    		if (data==null) {
				return;
			}
    		Bitmap mBitmap = data.getParcelableExtra("bitmap");
    		final String result = data.getStringExtra("result");
    		Logger.getLogger().i(result+" -- "+mBitmap);
    		View view = LayoutInflater.from(this).inflate(R.layout.scan, null);
    		ImageView icon = (ImageView) view.findViewById(R.id.iv_scan_icon);
    		TextView textView = (TextView) view.findViewById(R.id.tv_scan_title);
    		icon.setImageBitmap(mBitmap);
    		textView.setText(result);
    		AlertDialog.Builder dialog = new AlertDialog.Builder(this);
    		dialog.setTitle("扫描结果");
    		dialog.setView(view);
    		dialog.setMessage(data.getDataString());
    		dialog.setNegativeButton("确定", new DialogInterface.OnClickListener() {
    			@Override
    			public void onClick(DialogInterface dialog, int which) {
    				// 用默认浏览器打开扫描得到的地址
    				Intent intent = new Intent();
    				intent.setAction("android.intent.action.VIEW");
    				Uri content_url = Uri.parse(result);
    				intent.setData(content_url);
    				startActivity(intent);
    				dialog.dismiss();
    			}
    		});
    		dialog.setPositiveButton("取消", new DialogInterface.OnClickListener() {
    			@Override
    			public void onClick(DialogInterface dialog, int which) {
    				 dialog.dismiss();
    			}
    		});
    		dialog.create().show();
		}
    	super.onActivityResult(requestCode, resultCode, data);
    }

/**
 * @类功能说明: 生成二维码图片示例
 */
public class CreateQRImageTest {
	private ImageView sweepIV;
	private int QR_WIDTH = 200, QR_HEIGHT = 200;

	/**
	 * @方法功能说明: 生成二维码图片,实际使用时要初始化sweepIV,不然会报空指针错误
	 * @参数: @param url 要转换的地址或字符串,可以是中文
	 * @return void
	 * @throws
	 */

	// 要转换的地址或字符串,可以是中文
	public void createQRImage(String url) {
		try {
			// 判断URL合法性
			if (url == null || "".equals(url) || url.length() < 1) {
				return;
			}
			Hashtable<EncodeHintType, String> hints = new Hashtable<EncodeHintType, String>();
			hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
			// 图像数据转换，使用了矩阵转换
			BitMatrix bitMatrix = new QRCodeWriter().encode(url,
					BarcodeFormat.QR_CODE, QR_WIDTH, QR_HEIGHT, hints);
			int[] pixels = new int[QR_WIDTH * QR_HEIGHT];
			// 下面这里按照二维码的算法，逐个生成二维码的图片，
			// 两个for循环是图片横列扫描的结果
			for (int y = 0; y < QR_HEIGHT; y++) {
				for (int x = 0; x < QR_WIDTH; x++) {
					if (bitMatrix.get(x, y)) {
						pixels[y * QR_WIDTH + x] = 0xff000000;
					} else {
						pixels[y * QR_WIDTH + x] = 0xffffffff;
					}
				}
			}
			// 生成二维码图片的格式，使用ARGB_8888
			Bitmap bitmap = Bitmap.createBitmap(QR_WIDTH, QR_HEIGHT,
					Bitmap.Config.ARGB_8888);
			bitmap.setPixels(pixels, 0, QR_WIDTH, 0, 0, QR_WIDTH, QR_HEIGHT);
			// 显示到一个ImageView上面
			sweepIV.setImageBitmap(bitmap);
		} catch (WriterException e) {
			e.printStackTrace();
		}
	}
}

http://www.cnblogs.com/weixing/archive/2013/08/28/3287120.html

ZXing开源项目Google Code地址：https://code.google.com/p/zxing/

ZXingDemo下载：ZXingDemo2013-8-25.rar 

二、修改二维码代码

1、是扫描二维码的文字居中。

找到类ViewfinderView，其中widthPixels是屏幕的宽度。

paint.setColor(Color.WHITE);
paint.setTextSize(TEXT_SIZE * density);
paint.setAlpha(0x40);
paint.setTypeface(Typeface.create("System", Typeface.BOLD));
//获取文字宽度，让其居中显示
float wtext = paint.measureText(getResources().getString(R.string.scan_text));
canvas.drawText(getResources().getString(R.string.scan_text), (widthPixels-wtext)/2, (float) (frame.bottom + (float)TEXT_PADDING_TOP *density), paint);

找到CameraManager类的getFramingRect方法，就可以看到。

public Rect getFramingRect() {
    Point screenResolution = configManager.getScreenResolution();
    if (framingRect == null) {
      if (camera == null) {
        return null;
      }
      int width = screenResolution.x * 3 / 4;
      if (width < MIN_FRAME_WIDTH) {
        width = MIN_FRAME_WIDTH;
      } else if (width > MAX_FRAME_WIDTH) {
        width = MAX_FRAME_WIDTH;
      }
      int height = screenResolution.y * 3 / 4;
      if (height < MIN_FRAME_HEIGHT) {
        height = MIN_FRAME_HEIGHT;
      } else if (height > MAX_FRAME_HEIGHT) {
        height = MAX_FRAME_HEIGHT;
      }
      int leftOffset = (screenResolution.x - width) / 2;
      int topOffset = (screenResolution.y - height) / 2;
      framingRect = new Rect(leftOffset, topOffset, leftOffset + width, topOffset + height);
      Log.d(TAG, "Calculated framing rect: " + framingRect);
    }
    return framingRect;
  }

最近没事做了下二维码扫描，用的是ZXing的开源代码，官方源码地址：http://code.google.com/p/zxing/downloads/list；
我是在ZXing2.2基础上做的，因此只下载了ZXing-2.2.zip；
此外还需要ZXing的核心Jar包，下载地址：http://repo1.maven.org/maven2/com/google/zxing/core/2.2/，只需下载core-2.2.jar就行；
将下载的ZXing-2.2.zip解压出来，我们只需要用到android目录中的示例项目，如图：
 
将android项目导入eclipse，同时别忘了将core-2.2.jar导入libs，此时该示例项目应该可以运行了，不过该项目很多功能我们不需要，并且其扫描界面为横向的，因此需对其修改。

接下去我们来将该示例项目简化：
第一步：拷贝必要的包和类
新建自己的项目并导入core-2.2.jar，将示例项目中的必要代码全部拷贝到自己的项目中，至于示例项目中各个包和类的功能此处就不做解释的，有兴趣可以自己去研究下；
我自己对包结构做了一点改动，导入完成后会有很多红叉，大都和包的访问权限有关，因为示例代码中很多类是final型的，我们将其public就行；
此外还需要res下一些关联的文件（values下的color.xml、ids.xml、strings.xml，raw下的beep.ogg）。
初步调整后包结构如下：
 

第二步：PreferencesActivity和CaptureActivity修改
示例项目用到了大量的配置，因此很多地方都用到了PreferencesActivity这个类，其实留着它也无所谓，但别忘了将示例项目中res下一些关联文件拷贝过来（preferences.xml、arrays.xml）；
不过PreferencesActivity完全是多余的，看着也碍眼，因此我将其去掉，需要将用到PreferencesActivity的类都修改，就是剩余那些报红叉的类，我们需要将一些配置固定化，多余的设置判断去掉，此处我就不贴代码了；
同样CaptureActivity中也有很多方法是我们不需要的，大都是关于解码成功后的处理，如果要保留的话则需要额外拷贝很多类，因此将其去掉，此处也不贴代码了，附件源码中都有。

第三部：修改为竖屏
经过上面两步，我们自己的项目应该可以运行了（别忘了加权限），当然此时是横屏的，因此我们需要修改几处地方将其修改为竖屏：
1.CameraConfigurationManager类的initFromCameraParameters()方法中将以下代码注释掉：

http://blog.csdn.net/xinchen200/article/details/18036695