Android studio 二维码开源项目ZXing使用详解

ZXing的github

https://github.com/zxing/zxing

ZXing的库很大。但是我们需要的只有以下三个

首先新建一个Project，将android(Eclipse 工程) 导入到Project中，并改为library（鹅，不会的百度）,直接导入是会报错的，因为缺少一些东西，把刚android-studio中的CameraConfigurationUtils.java也加入到导入的module。

接着就是core的jar包

引用 ：Android Studio生成自定义jar包

新建一个library的module，将core中的代码拷贝进去，然后在gradle文件中配置

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:23.4.0'
}
 
def SDK_BASENAME = "TestSdk";
def SDK_VERSION = "_V1.0";
def sdkDestinationPath = "build";
def zipFile = file('build/intermediates/bundles/release/classes.jar')
 
task deleteBuild(type: Delete) {
    delete sdkDestinationPath + SDK_BASENAME + SDK_VERSION + ".jar"
}
 
task makeJar(type: Jar) {
    from zipTree(zipFile)
    from fileTree(dir: 'src/main',includes: ['assets/**'])
    baseName = SDK_BASENAME + SDK_VERSION
    destinationDir = file(sdkDestinationPath)
}
 
makeJar.dependsOn(deleteBuild, build)

SDK_BASENAME = "TestSdk";SDK_VERSION = "_V1.0"; 是定义生成jar的名字为TestSdk_V1.0.ja

接着打开studo的gradle视图，core->tast->other->makejar,运行makejar任务

成功后就生成了所需要的jar包，将jar放入到android的libs下

   

然后就是把剩下的错误改掉，就不详细说了

界面定制

引用：

链接1

链接2

CaptureActivity

ZXing暴露的调用Activity。在handleDecode方法中对扫码成功后的动作作处理。

public void handleDecode(Result rawResult, Bitmap barcode, float scaleFactor) {
    inactivityTimer.onActivity();
    String resultString = rawResult.getText();
    if (resultString.equals("")) {
      Toast.makeText(CaptureActivity.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);
    }
    finish();
  }

ViewfinderView

ZXing扫码窗口的绘制，原始的ZXing使用这种方式去绘制。我就直接引用别人定制的代码。

public final class ViewfinderView extends View {
  private static final String TAG = "log";
  /**
   * 刷新界面的时间
   */
  private static final long ANIMATION_DELAY = 10L;
  private static final int OPAQUE = 0xFF;

  /**
   * 四个绿色边角对应的长度
   */
  private int ScreenRate;

  /**
   * 四个绿色边角对应的宽度
   */
  private static final int CORNER_WIDTH = 10;
  /**
   * 扫描框中的中间线的宽度
   */
  private static final int MIDDLE_LINE_WIDTH = 6;

  /**
   * 扫描框中的中间线的与扫描框左右的间隙
   */
  private static final int MIDDLE_LINE_PADDING = 5;

  /**
   * 中间那条线每次刷新移动的距离
   */
  private static final int SPEEN_DISTANCE = 5;

  /**
   * 手机的屏幕密度
   */
  private static float density;
  /**
   * 字体大小
   */
  private static final int TEXT_SIZE = 16;
  /**
   * 字体距离扫描框下面的距离
   */
  private static final int TEXT_PADDING_TOP = 30;

  /**
   * 画笔对象的引用
   */
  private Paint paint;

  /**
   * 中间滑动线的最顶端位置
   */
  private int slideTop;

  /**
   * 中间滑动线的最底端位置
   */
  private int slideBottom;

  private Bitmap resultBitmap;
  private final int maskColor;
  private final int resultColor;

  private final int resultPointColor;
  private Collection possibleResultPoints;
  private Collection lastPossibleResultPoints;

  boolean isFirst;
  private CameraManager cameraManager;

  public ViewfinderView(Context context, AttributeSet attrs) {
    super(context, attrs);

    density = context.getResources().getDisplayMetrics().density;
    //将像素转换成dp
    ScreenRate = (int)(20 * density);

    paint = new Paint();
    Resources resources = getResources();
    maskColor = resources.getColor(R.color.viewfinder_mask);
    resultColor = resources.getColor(R.color.result_view);

    resultPointColor = resources.getColor(R.color.possible_result_points);
    possibleResultPoints = new HashSet(5);
  }

  public void setCameraManager(CameraManager cameraManager) {
    this.cameraManager = cameraManager;
  }

  @Override
  public void onDraw(Canvas canvas) {
    //中间的扫描框，你要修改扫描框的大小，去CameraManager里面修改
    Rect frame = cameraManager.getFramingRect();
    if (frame == null) {
      return;
    }

    //初始化中间线滑动的最上边和最下边
    if(!isFirst){
      isFirst = true;
      slideTop = frame.top;
      slideBottom = frame.bottom;
    }

    //获取屏幕的宽和高
    int width = canvas.getWidth();
    int height = canvas.getHeight();

    paint.setColor(resultBitmap != null ? resultColor : maskColor);

    //画出扫描框外面的阴影部分，共四个部分，扫描框的上面到屏幕上面，扫描框的下面到屏幕下面
    //扫描框的左边面到屏幕左边，扫描框的右边到屏幕右边
    canvas.drawRect(0, 0, width, frame.top, paint);
    canvas.drawRect(0, frame.top, frame.left, frame.bottom + 1, paint);
    canvas.drawRect(frame.right + 1, frame.top, width, frame.bottom + 1,
            paint);
    canvas.drawRect(0, frame.bottom + 1, width, height, paint);



    if (resultBitmap != null) {
      // Draw the opaque result bitmap over the scanning rectangle
      paint.setAlpha(OPAQUE);
      canvas.drawBitmap(resultBitmap, frame.left, frame.top, paint);
    } else {

      //画扫描框边上的角，总共8个部分
      paint.setColor(Color.GREEN);
      canvas.drawRect(frame.left, frame.top, frame.left + ScreenRate,
              frame.top + CORNER_WIDTH, paint);
      canvas.drawRect(frame.left, frame.top, frame.left + CORNER_WIDTH, frame.top
              + ScreenRate, paint);
      canvas.drawRect(frame.right - ScreenRate, frame.top, frame.right,
              frame.top + CORNER_WIDTH, paint);
      canvas.drawRect(frame.right - CORNER_WIDTH, frame.top, frame.right, frame.top
              + ScreenRate, paint);
      canvas.drawRect(frame.left, frame.bottom - CORNER_WIDTH, frame.left
              + ScreenRate, frame.bottom, paint);
      canvas.drawRect(frame.left, frame.bottom - ScreenRate,
              frame.left + CORNER_WIDTH, frame.bottom, paint);
      canvas.drawRect(frame.right - ScreenRate, frame.bottom - CORNER_WIDTH,
              frame.right, frame.bottom, paint);
      canvas.drawRect(frame.right - CORNER_WIDTH, frame.bottom - ScreenRate,
              frame.right, frame.bottom, paint);


      //绘制中间的线,每次刷新界面，中间的线往下移动SPEEN_DISTANCE
      slideTop += SPEEN_DISTANCE;
      if(slideTop >= frame.bottom){
        slideTop = frame.top;
      }
      canvas.drawRect(frame.left + MIDDLE_LINE_PADDING, slideTop - MIDDLE_LINE_WIDTH/2, frame.right - MIDDLE_LINE_PADDING,slideTop + MIDDLE_LINE_WIDTH/2, paint);


      //画扫描框下面的字
      paint.setColor(Color.WHITE);
      paint.setTextSize(TEXT_SIZE * density);
      paint.setAlpha(0x40);
      paint.setTypeface(Typeface.create("System", Typeface.BOLD));
      canvas.drawText(getResources().getString(R.string.scan_text), frame.left, (float) (frame.bottom + (float)TEXT_PADDING_TOP *density), paint);



      Collection currentPossible = possibleResultPoints;
      Collection currentLast = lastPossibleResultPoints;
      if (currentPossible.isEmpty()) {
        lastPossibleResultPoints = null;
      } else {
        possibleResultPoints = new HashSet(5);
        lastPossibleResultPoints = currentPossible;
        paint.setAlpha(OPAQUE);
        paint.setColor(resultPointColor);
        for (ResultPoint point : currentPossible) {
          canvas.drawCircle(frame.left + point.getX(), frame.top
                  + point.getY(), 6.0f, paint);
        }
      }
      if (currentLast != null) {
        paint.setAlpha(OPAQUE / 2);
        paint.setColor(resultPointColor);
        for (ResultPoint point : currentLast) {
          canvas.drawCircle(frame.left + point.getX(), frame.top
                  + point.getY(), 3.0f, paint);
        }
      }


      //只刷新扫描框的内容，其他地方不刷新
      postInvalidateDelayed(ANIMATION_DELAY, frame.left, frame.top,
              frame.right, frame.bottom);

    }
  }

  public void drawViewfinder() {
    resultBitmap = null;
    invalidate();
  }

  /**
   * Draw a bitmap with the result points highlighted instead of the live
   * scanning display.
   *
   * @param barcode
   *            An image of the decoded barcode.
   */
  public void drawResultBitmap(Bitmap barcode) {
    resultBitmap = barcode;
    invalidate();
  }

  public void addPossibleResultPoint(ResultPoint point) {
    possibleResultPoints.add(point);
  }

}

CameraConfigurationManager

修改横竖屏、处理变形效果的核心类。源码用的是横屏，如果切换竖屏图像会变形。

在public void setDesiredCameraParameters(Camera camera, boolean safeMode)方法可以将扫描改为竖屏：zai

在Log.i(TAG, "Screen resolution in current orientation: " + screenResolution); 后添加

Point screenResolutionForCamera = new Point();
screenResolutionForCamera.x = screenResolution.x;
screenResolutionForCamera.y = screenResolution.y;

if (screenResolution.x < screenResolution.y) {
  screenResolutionForCamera.x = screenResolution.y;
  screenResolutionForCamera.y = screenResolution.x;
}

然后修改如下代码

cameraResolution = CameraConfigurationUtils.findBestPreviewSizeValue(parameters, screenResolutionForCamera);
bestPreviewSize = CameraConfigurationUtils.findBestPreviewSizeValue(parameters, screenResolutionForCamera);

EncodeingUtils.java 将文字转换为二维码的工具类

public class EncodingUtils {
    public static final Bitmap createQRCode(String contentsToEncode,int dimension) {
        if (contentsToEncode == null) {
            return null;
        }
        Map hints = null;
        String encoding = guessAppropriateEncoding(contentsToEncode);
        if (encoding != null) {
            hints = new EnumMap<>(EncodeHintType.class);
            hints.put(EncodeHintType.CHARACTER_SET, encoding);
        }
        BitMatrix result;
        try {
            BarcodeFormat barcodeFormat = BarcodeFormat.QR_CODE;
            result = new MultiFormatWriter().encode(contentsToEncode,  barcodeFormat, dimension, dimension, hints);
        } catch (Exception iae) {
            // Unsupported format
            return null;
        }
        int width = result.getWidth();
        int height = result.getHeight();
        int[] pixels = new int[width * height];
        for (int y = 0; y < height; y++) {
            int offset = y * width;
            for (int x = 0; x < width; x++) {
                pixels[offset + x] = result.get(x, y) ? BLACK : WHITE;
            }
        }

        Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
        bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
        return bitmap;
    }

    private static String guessAppropriateEncoding(CharSequence contents) {
        // Very crude at the moment
        for (int i = 0; i < contents.length(); i++) {
            if (contents.charAt(i) > 0xFF) {
                return "UTF-8";
            }
        }
        return null;
    }

}

还有些细节上的调整就不说了，自己看看也能搞定了.

接着就是例子了

public class MainActivity extends AppCompatActivity {
    private TextView tvShow;
    private EditText etInput;
    private ImageView ivQR;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        tvShow = (TextView) findViewById(R.id.show);
        etInput = (EditText) findViewById(R.id.input);
        ivQR = (ImageView) findViewById(R.id.iv);

    }

    public void scan(View view){
        Toast.makeText(this, "可以开始扫描", Toast.LENGTH_SHORT).show();
        Intent intent=new Intent();
        intent.setClass(this, CaptureActivity.class);
        startActivityForResult(intent,0);
    }

    public void gene(View view){
        String input=etInput.getText().toString();
        if (TextUtils.isEmpty(input)) {

        }
        else {
            try {

                Bitmap qrCode = EncodingUtils.createQRCode(input,400);
                ivQR.setImageBitmap(qrCode);
            } catch (Exception e) {
                // TODO Auto-generated catch block
                e.printStackTrace();

            }
        }

    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (resultCode==RESULT_OK) {
            String result=data.getStringExtra("result");
            tvShow.setText(result);
        }
    }

最后附上github地址

https://github.com/keroro2015/ZXing