最近项目用到了二维码的生成与识别,之前没有接触这块,然后就上网搜了搜,发现有好多这方面的资源,特别是google Zxing对二维码的封装,实现的已经不错了,可以直接拿过来引用,下载了他们的源码后,只做了少少的改动,就是在Demo中增加了长按识别的功能,网上虽然也有长按识别的Demo,但好多下载下来却无法运行,然后总结了一下,加在了下面的Demo中。
下面来介绍这个Demo的主类
public class BarCodeTestActivity extends Activity { private TextView resultTextView; private EditText qrStrEditText; private ImageView qrImgImageView; private String time;private File file = null;@Overridepublic 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) { //打开扫描界面扫描条形码或二维码 Intent openCameraIntent = new Intent(BarCodeTestActivity.this,CaptureActivity.class); startActivityForResult(openCameraIntent, 0); } }); qrImgImageView.setOnLongClickListener(new OnLongClickListener() {@Override public boolean onLongClick(View v) { // 长按识别二维码 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("")) { //根据字符串生成二维码图片并显示在界面上,第二个参数为图片的大小(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(); } } });} //这种方法状态栏是空白,显示不了状态栏的信息private void saveCurrentImage(){ //获取当前屏幕的大小 int width = getWindow().getDecorView().getRootView().getWidth(); int height = getWindow().getDecorView().getRootView().getHeight(); //生成相同大小的图片 Bitmap temBitmap = Bitmap.createBitmap( width, height, Bitmap.Config.ARGB_8888 ); //找到当前页面的根布局 View view = getWindow().getDecorView().getRootView(); //设置缓存 view.setDrawingCacheEnabled(true); view.buildDrawingCache(); //从缓存中获取当前屏幕的图片,创建一个DrawingCache的拷贝,因为DrawingCache得到的位图在禁用后会被回收 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 blocke.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, "无法识别", Toast.LENGTH_LONG).show(); } }}); }}).start();//禁用DrawingCahce否则会影响性能 ,而且不禁止会导致每次截图到保存的是缓存的位图view.setDrawingCacheEnabled(false); }}//解析二维码图片,返回结果封装在Result对象中private com.google.zxing.Result parseQRcodeBitmap(String bitmapPath){ //解析转换类型UTF-8 Hashtable<DecodeHintType, String> hints = new Hashtable<DecodeHintType, String>(); hints.put(DecodeHintType.CHARACTER_SET, "utf-8"); //获取到待解析的图片 BitmapFactory.Options options = new BitmapFactory.Options();//如果我们把inJustDecodeBounds设为true,那么BitmapFactory.decodeFile(String path, Options opt) //并不会真的返回一个Bitmap给你,它仅仅会把它的宽,高取回来给你 options.inJustDecodeBounds = true; //此时的bitmap是null,这段代码之后,options.outWidth 和 options.outHeight就是我们想要的宽和高了 Bitmap bitmap = BitmapFactory.decodeFile(bitmapPath,options); //我们现在想取出来的图片的边长(二维码图片是正方形的)设置为400像素 /**options.outHeight = 400;options.outWidth = 400;options.inJustDecodeBounds = false;bitmap = BitmapFactory.decodeFile(bitmapPath, options); */ //以上这种做法,虽然把bitmap限定到了我们要的大小,但是并没有节约内存,如果要节约内存,我们还需要使用inSimpleSize这个属性 options.inSampleSize = options.outHeight / 400; if(options.inSampleSize <= 0){options.inSampleSize = 1; //防止其值小于或等于0 } /*** 辅助节约内存设置** options.inPreferredConfig = Bitmap.Config.ARGB_4444; // 默认是Bitmap.Config.ARGB_8888* options.inPurgeable = true;* options.inInputShareable = true;*/ options.inJustDecodeBounds = false; bitmap = BitmapFactory.decodeFile(bitmapPath, options);//新建一个RGBLuminanceSource对象,将bitmap图片传给此对象 RGBLuminanceSource rgbLuminanceSource = new RGBLuminanceSource(bitmap); //将图片转换成二进制图片 BinaryBitmap binaryBitmap = new BinaryBitmap(new HybridBinarizer(rgbLuminanceSource)); //初始化解析对象 QRCodeReader reader = new QRCodeReader(); //开始解析 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); //处理扫描结果(在界面上显示) if (resultCode == RESULT_OK) { Bundle bundle = data.getExtras(); String scanResult = bundle.getString("result"); resultTextView.setText(scanResult); } } } 然后长按识别二维码调用了RGBLuminanceSource这个类
public class RGBLuminanceSource extends LuminanceSource { private byte bitmapPixels[];protected RGBLuminanceSource(Bitmap bitmap) { super(bitmap.getWidth(), bitmap.getHeight());// 首先,要取得该图片的像素数组内容 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());// 将int数组转换为byte数组,也就是取像素值中蓝色值部分作为辨析内容 for (int i = 0; i < data.length; i++) { this.bitmapPixels[i] = (byte) data[i]; } }@Override public byte[] getMatrix() { // 返回我们生成好的像素数据 return bitmapPixels; } @Override public byte[] getRow(int y, byte[] row) { // 这里要得到指定行的像素数据 System.arraycopy(bitmapPixels, y * getWidth(), row, 0, getWidth()); return row; } } 相机识别二维码调用了CaptureActivity这个类
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("")) { //扫描失败 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>
详细了解的请下载demo自己看,Demo中解决了在竖拍解码时二维码被拉伸的现象。
不过我遇到了一个问题是 二维码的扫描框调大后,扫描的灵敏度降低了,希望知道的朋友给指导下
有兴趣的可以下载Demo看一看:google Zxing实现二维码的生成
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。