Android基於google Zxing實現二維碼的生成

　　最近項目用到了二維碼的生成與識別，之前沒有接觸這塊，然後就上網搜了搜，發現有好多這方面的資源，特別是google Zxing對二維碼的封裝，實現的已經不錯了，可以直接拿過來引用，下載了他們的源碼後，只做了少少的改動，就是在Demo中增加了長按識別的功能，網上雖然也有長按識別的Demo，但好多下載下來卻無法運行，然後總結了一下，加在了下面的Demo中。

　　下面來介紹這個Demo的主類
 

public class BarCodeTestActivity extends Activity { 
  
private TextView resultTextView; 
private EditText qrStrEditText; 
private ImageView qrImgImageView; 
private String time; 
 private File file = null; 
 @Override 
 public void onCreate(Bundle savedInstanceState) { 
  super.onCreate(savedInstanceState); 
  setContentView(R.layout.main);   
  resultTextView = (TextView) this.findViewById(R.id.tv_scan_result); 
  qrStrEditText = (EditText) this.findViewById(R.id.et_qr_string); 
  qrImgImageView = (ImageView) this.findViewById(R.id.iv_qr_image); 
   
  Button scanBarCodeButton = (Button) this.findViewById(R.id.btn_scan_barcode); 
  scanBarCodeButton.setOnClickListener(new OnClickListener() { 
 
@Override 
public void onClick(View v) { 
//打開掃描界面掃描條形碼或二維碼 
Intent openCameraIntent = new Intent(BarCodeTestActivity.this,CaptureActivity.class); 
startActivityForResult(openCameraIntent, 0); 
} 
}); 
qrImgImageView.setOnLongClickListener(new OnLongClickListener() { 
 
@Override 
public boolean onLongClick(View v) { 
// 長按識別二維碼 
 
 saveCurrentImage(); 
return true; 
} 
});   
  Button generateQRCodeButton = (Button) this.findViewById(R.id.btn_add_qrcode); 
  generateQRCodeButton.setOnClickListener(new OnClickListener() { 
 
@Override 
public void onClick(View v) { 
try { 
String contentString = qrStrEditText.getText().toString(); 
if (!contentString.equals("")) { 
//根據字符串生成二維碼圖片並顯示在界面上，第二個參數為圖片的大小（350*350） 
Bitmap qrCodeBitmap = EncodingHandler.createQRCode(contentString, 350); 
qrImgImageView.setImageBitmap(qrCodeBitmap); 
}else { 
//提示文本不能是空的 
Toast.makeText(BarCodeTestActivity.this, "Text can not be empty", Toast.LENGTH_SHORT).show(); 
} 
 
} catch (WriterException e) { 
// TODO Auto-generated catch block 
e.printStackTrace(); 
} 
} 
}); 
 } 
 
 //這種方法狀態欄是空白，顯示不了狀態欄的信息 
 private void saveCurrentImage() 
 { 
  //獲取當前屏幕的大小 
  int width = getWindow().getDecorView().getRootView().getWidth(); 
  int height = getWindow().getDecorView().getRootView().getHeight(); 
  //生成相同大小的圖片 
  Bitmap temBitmap = Bitmap.createBitmap( width, height, Bitmap.Config.ARGB_8888 ); 
  //找到當前頁面的根布局 
  View view = getWindow().getDecorView().getRootView(); 
  //設置緩存 
  view.setDrawingCacheEnabled(true); 
  view.buildDrawingCache(); 
  //從緩存中獲取當前屏幕的圖片,創建一個DrawingCache的拷貝，因為DrawingCache得到的位圖在禁用後會被回收 
  temBitmap = view.getDrawingCache(); 
  SimpleDateFormat df = new SimpleDateFormat("yyyymmddhhmmss"); 
  time = df.format(new Date()); 
  if(Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState())){ 
   file = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/screen",time + ".png"); 
   if(!file.exists()){ 
    file.getParentFile().mkdirs(); 
    try { 
     file.createNewFile(); 
    } catch (IOException e) { 
     // TODO Auto-generated catch block 
     e.printStackTrace(); 
    } 
   } 
   FileOutputStream fos = null; 
   try { 
    fos = new FileOutputStream(file); 
    temBitmap.compress(Bitmap.CompressFormat.PNG, 100, fos); 
    fos.flush(); 
    fos.close(); 
   } catch (FileNotFoundException e) { 
    e.printStackTrace(); 
   } catch (IOException e) { 
    // TODO Auto-generated catch block 
    e.printStackTrace(); 
   } 
   new Thread(new Runnable() { 
    @Override 
    public void run() { 
     String path = Environment.getExternalStorageDirectory().getAbsolutePath() + "/screen/" + time + ".png"; 
     final Result result = parseQRcodeBitmap(path); 
     runOnUiThread(new Runnable() { 
      public void run() { 
      if(null!=result){ 
      resultTextView.setText(result.toString()); 
      }else{ 
       Toast.makeText(BarCodeTestActivity.this, "無法識別", Toast.LENGTH_LONG).show(); 
      } 
      } 
     }); 
    } 
   }).start(); 
   //禁用DrawingCahce否則會影響性能 ,而且不禁止會導致每次截圖到保存的是緩存的位圖 
   view.setDrawingCacheEnabled(false); 
  } 
 } 
  
 //解析二維碼圖片,返回結果封裝在Result對象中 
 private com.google.zxing.Result parseQRcodeBitmap(String bitmapPath){ 
  //解析轉換類型UTF-8 
  Hashtable<DecodeHintType, String> hints = new Hashtable<DecodeHintType, String>(); 
  hints.put(DecodeHintType.CHARACTER_SET, "utf-8"); 
  //獲取到待解析的圖片 
  BitmapFactory.Options options = new BitmapFactory.Options();  
  //如果我們把inJustDecodeBounds設為true，那麼BitmapFactory.decodeFile(String path, Options opt) 
  //並不會真的返回一個Bitmap給你，它僅僅會把它的寬，高取回來給你 
  options.inJustDecodeBounds = true; 
  //此時的bitmap是null，這段代碼之後，options.outWidth 和 options.outHeight就是我們想要的寬和高了 
  Bitmap bitmap = BitmapFactory.decodeFile(bitmapPath,options); 
  //我們現在想取出來的圖片的邊長（二維碼圖片是正方形的）設置為400像素 
  /** 
   options.outHeight = 400; 
   options.outWidth = 400; 
   options.inJustDecodeBounds = false; 
   bitmap = BitmapFactory.decodeFile(bitmapPath, options); 
  */ 
  //以上這種做法，雖然把bitmap限定到了我們要的大小，但是並沒有節約內存，如果要節約內存，我們還需要使用inSimpleSize這個屬性 
  options.inSampleSize = options.outHeight / 400; 
  if(options.inSampleSize <= 0){ 
   options.inSampleSize = 1; //防止其值小於或等於0 
  } 
  /** 
   * 輔助節約內存設置 
   * 
   * options.inPreferredConfig = Bitmap.Config.ARGB_4444; // 默認是Bitmap.Config.ARGB_8888 
   * options.inPurgeable = true; 
   * options.inInputShareable = true; 
   */ 
  options.inJustDecodeBounds = false; 
  bitmap = BitmapFactory.decodeFile(bitmapPath, options);  
  //新建一個RGBLuminanceSource對象，將bitmap圖片傳給此對象 
  RGBLuminanceSource rgbLuminanceSource = new RGBLuminanceSource(bitmap); 
  //將圖片轉換成二進制圖片 
  BinaryBitmap binaryBitmap = new BinaryBitmap(new HybridBinarizer(rgbLuminanceSource)); 
  //初始化解析對象 
  QRCodeReader reader = new QRCodeReader(); 
  //開始解析 
  Result result = null; 
  try { 
   result = reader.decode(binaryBitmap, hints); 
  } catch (Exception e) { 
   // TODO: handle exception 
  } 
   
  return result; 
 } 
 
@Override 
protected void onActivityResult(int requestCode, int resultCode, Intent data) { 
super.onActivityResult(requestCode, resultCode, data); 
//處理掃描結果（在界面上顯示） 
if (resultCode == RESULT_OK) { 
Bundle bundle = data.getExtras(); 
String scanResult = bundle.getString("result"); 
resultTextView.setText(scanResult); 
} 
} 
} 
然後長按識別二維碼調用了RGBLuminanceSource這個類
public class RGBLuminanceSource extends LuminanceSource { 
private byte bitmapPixels[]; 
 
protected RGBLuminanceSource(Bitmap bitmap) { 
super(bitmap.getWidth(), bitmap.getHeight()); 
 
// 首先，要取得該圖片的像素數組內容 
int[] data = new int[bitmap.getWidth() * bitmap.getHeight()]; 
this.bitmapPixels = new byte[bitmap.getWidth() * bitmap.getHeight()]; 
bitmap.getPixels(data, 0, getWidth(), 0, 0, getWidth(), getHeight()); 
 
// 將int數組轉換為byte數組，也就是取像素值中藍色值部分作為辨析內容 
for (int i = 0; i < data.length; i++) { 
this.bitmapPixels[i] = (byte) data[i]; 
} 
} 
 
@Override 
public byte[] getMatrix() { 
// 返回我們生成好的像素數據 
return bitmapPixels; 
} 
 
 
@Override 
public byte[] getRow(int y, byte[] row) { 
// 這裡要得到指定行的像素數據 
System.arraycopy(bitmapPixels, y * getWidth(), row, 0, getWidth()); 
return row; 
} 
} 
相機識別二維碼調用了CaptureActivity這個類  
public class CaptureActivity extends Activity 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; 
private Button cancelScanButton; 
 
/** Called when the activity is first created. */ 
@Override 
public void onCreate(Bundle savedInstanceState) { 
super.onCreate(savedInstanceState); 
setContentView(R.layout.camera); 
 
CameraManager.init(getApplication()); 
viewfinderView = (ViewfinderView) findViewById(R.id.viewfinder_view); 
cancelScanButton = (Button) this.findViewById(R.id.btn_cancel_scan); 
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; 
 
//quit the scan view 
cancelScanButton.setOnClickListener(new OnClickListener() { 
 
@Override 
public void onClick(View v) { 
CaptureActivity.this.finish(); 
} 
}); 
} 
 
@Override 
protected void onPause() { 
super.onPause(); 
if (handler != null) { 
handler.quitSynchronously(); 
handler = null; 
} 
CameraManager.get().closeDriver(); 
} 
 
@Override 
protected void onDestroy() { 
inactivityTimer.shutdown(); 
super.onDestroy(); 
} 
 
/** 
* Handler scan result 
* @param result 
* @param barcode 
*/ 
public void handleDecode(Result result, Bitmap barcode) { 
inactivityTimer.onActivity(); 
playBeepSoundAndVibrate(); 
String resultString = result.getText(); 
//FIXME 
if (resultString.equals("")) { 
//掃描失敗 
Toast.makeText(CaptureActivity.this, "Scan failed!", Toast.LENGTH_SHORT).show(); 
}else { 
// System.out.println("Result:"+resultString); 
Intent resultIntent = new Intent(); 
Bundle bundle = new Bundle(); 
bundle.putString("result", resultString); 
resultIntent.putExtras(bundle); 
this.setResult(RESULT_OK, resultIntent); 
} 
CaptureActivity.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); 
} 
}; 
 
 
} 

　　下面是主布局mian文件
 

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
 android:layout_width="fill_parent" 
 android:layout_height="fill_parent" 
 android:background="@android:color/white" 
 android:orientation="vertical" > 
 
 
 <Button 
  android:id="@+id/btn_scan_barcode" 
  android:layout_width="fill_parent" 
  android:layout_height="wrap_content" 
  android:layout_marginTop="30dp" 
  android:text="Open camera" /> 
  
 <LinearLayout 
  android:orientation="horizontal" 
  android:layout_marginTop="10dp" 
  android:layout_width="fill_parent" 
  android:layout_height="wrap_content"> 
   
  <TextView 
  android:layout_width="wrap_content" 
  android:layout_height="wrap_content" 
  android:textColor="@android:color/black" 
  android:textSize="18sp" 
  android:text="Scan result：" /> 
   
  <TextView 
  android:id="@+id/tv_scan_result" 
  android:layout_width="fill_parent" 
  android:textSize="18sp" 
  android:textColor="@android:color/black" 
  android:layout_height="wrap_content" /> 
 </LinearLayout> 
  
 <EditText 
  android:id="@+id/et_qr_string" 
  android:layout_width="fill_parent" 
  android:layout_height="wrap_content" 
  android:layout_marginTop="30dp" 
  android:hint="Input the text"/> 
  
 <Button 
  android:id="@+id/btn_add_qrcode" 
  android:layout_width="fill_parent" 
  android:layout_height="wrap_content" 
  android:text="Generate QRcode" /> 
  
 <ImageView 
  android:id="@+id/iv_qr_image" 
  android:layout_width="250dp" 
  android:layout_height="250dp" 
  android:scaleType="fitXY" 
  android:layout_marginTop="10dp" 
  android:layout_gravity="center"/> 
 
 
</LinearLayout>

　　詳細了解的請下載demo自己看，Demo中解決了在豎拍解碼時二維碼被拉伸的現象。

　　不過我遇到了一個問題是 二維碼的掃描框調大後，掃描的靈敏度降低了，希望知道的朋友給指導下。