安卓实现二维码生成和扫描功能，扫描支持直接拍照扫码和相册图片扫码，还加了照明功能

最近在做二维码的生成和扫描，生成二维码相对而言较为简单，扫描相对复杂，遇到的问题较多，但是在实现二维码的生成和扫描之前最重要的一步

就是讲Zxing包导入，后面的内容大部分是使用包中的内容，

那我就从二维码的生成讲起吧！

二维码生成：

直接贴代码了

 //要转换的地址或字符串,可以是中文，输入内容生成二维码
    public Bitmap createQRImage(String string) {
        try {
            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(string, 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);
            return bitmap;
        } catch (WriterException e) {
            e.printStackTrace();
        }


        return null;
    }

使用这个方法即可生成二维码了

接下来是扫描二维码了

扫描二维码：

我百度了一下，哟不少需要我们自己写的，太多了，我就不一一一写了，就贴出我认为比较重要的两个，一个是CameraManager，一个是ViewfinderView

这两个都可以我们根据自己的爱好相对于的修改样式或扫描框的大小，上代码了

ViewfinderView：

    private static final String TAG = "log";
    /**
     * 刷新界面的时间
     */
    private static final long ANIMATION_DELAY = 30L;
    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 frameColor;
    private final int resultPointColor;
    private Collection<ResultPoint> possibleResultPoints;
    private Collection<ResultPoint> lastPossibleResultPoints;

    boolean isFirst;

    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);
        frameColor = resources.getColor(R.color.viewfinder_frame);
        resultPointColor = resources.getColor(R.color.possible_result_points);
        possibleResultPoints = new HashSet<ResultPoint>(5);
    }

    @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.get().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 {
//这是我自己加的扫描框内部的白线，让扫描框看起来更好看
            paint.setColor(frameColor);
            canvas.drawRect(frame.left + CORNER_WIDTH, frame.top + CORNER_WIDTH, frame.right + 1 - CORNER_WIDTH, frame.top + 2 + CORNER_WIDTH, paint);
            canvas.drawRect(frame.left + CORNER_WIDTH, frame.top + 2 + CORNER_WIDTH, frame.left + 2 + CORNER_WIDTH, frame.bottom - 1 - CORNER_WIDTH, paint);
            canvas.drawRect(frame.right - 1 - CORNER_WIDTH, frame.top + CORNER_WIDTH, frame.right + 1 - CORNER_WIDTH, frame.bottom - 1 - CORNER_WIDTH, paint);
            canvas.drawRect(frame.left + CORNER_WIDTH, frame.bottom - 1 - CORNER_WIDTH, frame.right + 1 - CORNER_WIDTH, frame.bottom + 1 - CORNER_WIDTH, paint);

            //画扫描框边上的角，总共8个部分
            paint.setColor(Color.parseColor("#FF038CF7"));
            //左上
            canvas.drawRect(frame.left, frame.top - CORNER_WIDTH, frame.left + ScreenRate,
                    frame.top + CORNER_WIDTH - CORNER_WIDTH, paint);
            canvas.drawRect(frame.left - CORNER_WIDTH, frame.top - CORNER_WIDTH, frame.left + CORNER_WIDTH - CORNER_WIDTH, frame.top
                    + ScreenRate - CORNER_WIDTH + CORNER_WIDTH, paint);
            //右上
            canvas.drawRect(frame.right - ScreenRate, frame.top - CORNER_WIDTH, frame.right + CORNER_WIDTH,
                    frame.top + CORNER_WIDTH - CORNER_WIDTH, paint);
            canvas.drawRect(frame.right - CORNER_WIDTH + CORNER_WIDTH, frame.top, frame.right + CORNER_WIDTH, frame.top
                    + ScreenRate, paint);
            //左下
            canvas.drawRect(frame.left - CORNER_WIDTH, frame.bottom - ScreenRate, frame.left + CORNER_WIDTH - CORNER_WIDTH
                    , frame.bottom, paint);
            canvas.drawRect(frame.left - CORNER_WIDTH, frame.bottom,
                    frame.left + ScreenRate, frame.bottom + CORNER_WIDTH, paint);
            //右下
            canvas.drawRect(frame.right, frame.bottom - ScreenRate,
                    frame.right + CORNER_WIDTH, frame.bottom, paint);
            canvas.drawRect(frame.right - ScreenRate, frame.bottom,
                    frame.right + CORNER_WIDTH, frame.bottom + CORNER_WIDTH, 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<ResultPoint> currentPossible = possibleResultPoints;
            Collection<ResultPoint> currentLast = lastPossibleResultPoints;
            if (currentPossible.isEmpty()) {
                lastPossibleResultPoints = null;
            } else {
                possibleResultPoints = new HashSet<ResultPoint>(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);
    }

CameraManager：

private static final String TAG = CameraManager.class.getSimpleName();

  private static final int MIN_FRAME_WIDTH = 240;
  private static final int MIN_FRAME_HEIGHT = 240;
  private static final int MAX_FRAME_WIDTH = 720;
  private static final int MAX_FRAME_HEIGHT = 480;

  private static CameraManager cameraManager;

  static final int SDK_INT; // Later we can use Build.VERSION.SDK_INT
  static {
    int sdkInt;
    try {
      sdkInt = Integer.parseInt(Build.VERSION.SDK);
    } catch (NumberFormatException nfe) {
      // Just to be safe
      sdkInt = 10000;
    }
    SDK_INT = sdkInt;
  }

  private final Context context;
  private final CameraConfigurationManager configManager;
  private Camera camera;
  private Rect framingRect;
  private Rect framingRectInPreview;
  private boolean initialized;
  private boolean previewing;
  private final boolean useOneShotPreviewCallback;
  /**
   * Preview frames are delivered here, which we pass on to the registered handler. Make sure to
   * clear the handler so it will only receive one message.
   */
  private final PreviewCallback previewCallback;
  /** Autofocus callbacks arrive here, and are dispatched to the Handler which requested them. */
  private final AutoFocusCallback autoFocusCallback;

  /**
   * Initializes this static object with the Context of the calling Activity.
   *
   * @param context The Activity which wants to use the camera.
   */
  public static void init(Context context) {
    if (cameraManager == null) {
      cameraManager = new CameraManager(context);
    }
  }

  /**
   * Gets the CameraManager singleton instance.
   *
   * @return A reference to the CameraManager singleton.
   */
  public static CameraManager get() {
    return cameraManager;
  }

  private CameraManager(Context context) {

    this.context = context;
    this.configManager = new CameraConfigurationManager(context);

    // Camera.setOneShotPreviewCallback() has a race condition in Cupcake, so we use the older
    // Camera.setPreviewCallback() on 1.5 and earlier. For Donut and later, we need to use
    // the more efficient one shot callback, as the older one can swamp the system and cause it
    // to run out of memory. We can't use SDK_INT because it was introduced in the Donut SDK.
    //useOneShotPreviewCallback = Integer.parseInt(Build.VERSION.SDK) > Build.VERSION_CODES.CUPCAKE;
    useOneShotPreviewCallback = Integer.parseInt(Build.VERSION.SDK) > 3; // 3 = Cupcake

    previewCallback = new PreviewCallback(configManager, useOneShotPreviewCallback);
    autoFocusCallback = new AutoFocusCallback();
  }
  //控制开启闪光灯
  public void flashHandler() {
    //camera.startPreview();
    Camera.Parameters parameters = camera.getParameters();
    // 判断闪光灯当前状态來修改
    if (Camera.Parameters.FLASH_MODE_OFF.equals(parameters.getFlashMode())) {
      turnOn(parameters);
    } else if (Camera.Parameters.FLASH_MODE_TORCH.equals(parameters.getFlashMode())) {
      turnOff(parameters);
    }
  }
  //开
  private void turnOn(Camera.Parameters parameters) {
    parameters.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);
    camera.setParameters(parameters);
  }
  //关
  private void turnOff(Camera.Parameters parameters) {
    parameters.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
    camera.setParameters(parameters);
  }
  /**
   * Opens the camera driver and initializes the hardware parameters.
   *
   * @param holder The surface object which the camera will draw preview frames into.
   * @throws IOException Indicates the camera driver failed to open.
   */
  public void openDriver(SurfaceHolder holder) throws IOException {

    if (camera == null) {
      System.out.println("wanggsx openDriver camera = null");
      camera = Camera.open();
      if (camera == null) {
        throw new IOException();
      }
      camera.setPreviewDisplay(holder);

      if (!initialized) {
        initialized = true;
        configManager.initFromCameraParameters(camera);
      }
      configManager.setDesiredCameraParameters(camera);
      FlashlightManager.enableFlashlight();
    } else {
      System.out.println("wangying openDriver camera != null");
      camera.setPreviewDisplay(holder);//此处为新增方法
    }
/***
 * 以上内容为更改内容，经实践结果我们发现，viewfinder会出现黑屏的情况，以上内容就是解决的方法，
 * 我遇到的情况是我从相册中选取图片进行扫描的时候，返回扫描界面的时候就出现viewFinder黑屏，大家复制上面
 * 的内容，放到这个方法就可以啦！
 */

//    if (camera == null) {
//      camera = Camera.open();
//      if (camera == null) {
//        throw new IOException();
//      }
//      camera.setPreviewDisplay(holder);
//
//      if (!initialized) {
//        initialized = true;
//        configManager.initFromCameraParameters(camera);
//      }
//      configManager.setDesiredCameraParameters(camera);

      //FIXME
 //     SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
      //�Ƿ�ʹ��ǰ��
//      if (prefs.getBoolean(PreferencesActivity.KEY_FRONT_LIGHT, false)) {
//        FlashlightManager.enableFlashlight();
//      }
//      FlashlightManager.enableFlashlight();
//    }
  }

  /**
   * Closes the camera driver if still in use.
   */
  public void closeDriver() {
    if (camera != null) {
      FlashlightManager.disableFlashlight();
      camera.release();
      camera = null;
    }
  }

  /**
   * Asks the camera hardware to begin drawing preview frames to the screen.
   */
  public void startPreview() {
    if (camera != null && !previewing) {
      camera.startPreview();
      previewing = true;
    }
  }

  /**
   * Tells the camera to stop drawing preview frames.
   */
  public void stopPreview() {
    if (camera != null && previewing) {
      if (!useOneShotPreviewCallback) {
        camera.setPreviewCallback(null);
      }
      camera.stopPreview();
      previewCallback.setHandler(null, 0);
      autoFocusCallback.setHandler(null, 0);
      previewing = false;
    }
  }

  /**
   * A single preview frame will be returned to the handler supplied. The data will arrive as byte[]
   * in the message.obj field, with width and height encoded as message.arg1 and message.arg2,
   * respectively.
   *
   * @param handler The handler to send the message to.
   * @param message The what field of the message to be sent.
   */
  public void requestPreviewFrame(Handler handler, int message) {
    if (camera != null && previewing) {
      previewCallback.setHandler(handler, message);
      if (useOneShotPreviewCallback) {
        camera.setOneShotPreviewCallback(previewCallback);
      } else {
        camera.setPreviewCallback(previewCallback);
      }
    }
  }

  /**
   * Asks the camera hardware to perform an autofocus.
   *
   * @param handler The Handler to notify when the autofocus completes.
   * @param message The message to deliver.
   */
  public void requestAutoFocus(Handler handler, int message) {
    if (camera != null && previewing) {
      autoFocusCallback.setHandler(handler, message);
      //Log.d(TAG, "Requesting auto-focus callback");
      camera.autoFocus(autoFocusCallback);
    }
  }

  /**
   * Calculates the framing rect which the UI should draw to show the user where to place the
   * barcode. This target helps with alignment as well as forces the user to hold the device
   * far enough away to ensure the image will be in focus.
   *
   * @return The rectangle to draw on screen in window coordinates.
   */
  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 / 6;
      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;
  }

  /**
   * Like {@link #getFramingRect} but coordinates are in terms of the preview frame,
   * not UI / screen.
   */
  public Rect getFramingRectInPreview() {
    if (framingRectInPreview == null) {
      Rect rect = new Rect(getFramingRect());
      Point cameraResolution = configManager.getCameraResolution();
      Point screenResolution = configManager.getScreenResolution();
      //modify here
//      rect.left = rect.left * cameraResolution.x / screenResolution.x;
//      rect.right = rect.right * cameraResolution.x / screenResolution.x;
//      rect.top = rect.top * cameraResolution.y / screenResolution.y;
//      rect.bottom = rect.bottom * cameraResolution.y / screenResolution.y;
      rect.left = rect.left * cameraResolution.y / screenResolution.x;
      rect.right = rect.right * cameraResolution.y / screenResolution.x;
      rect.top = rect.top * cameraResolution.x / screenResolution.y;
      rect.bottom = rect.bottom * cameraResolution.x / screenResolution.y;
      framingRectInPreview = rect;
    }
    return framingRectInPreview;
  }

  /**
   * Converts the result points from still resolution coordinates to screen coordinates.
   *
   * @param points The points returned by the Reader subclass through Result.getResultPoints().
   * @return An array of Points scaled to the size of the framing rect and offset appropriately
   *         so they can be drawn in screen coordinates.
   */
  /*
  public Point[] convertResultPoints(ResultPoint[] points) {
    Rect frame = getFramingRectInPreview();
    int count = points.length;
    Point[] output = new Point[count];
    for (int x = 0; x < count; x++) {
      output[x] = new Point();
      output[x].x = frame.left + (int) (points[x].getX() + 0.5f);
      output[x].y = frame.top + (int) (points[x].getY() + 0.5f);
    }
    return output;
  }
   */

  /**
   * A factory method to build the appropriate LuminanceSource object based on the format
   * of the preview buffers, as described by Camera.Parameters.
   *
   * @param data A preview frame.
   * @param width The width of the image.
   * @param height The height of the image.
   * @return A PlanarYUVLuminanceSource instance.
   */
  public PlanarYUVLuminanceSource buildLuminanceSource(byte[] data, int width, int height) {
    Rect rect = getFramingRectInPreview();
    int previewFormat = configManager.getPreviewFormat();
    String previewFormatString = configManager.getPreviewFormatString();
    switch (previewFormat) {
      // This is the standard Android format which all devices are REQUIRED to support.
      // In theory, it's the only one we should ever care about.
      case PixelFormat.YCbCr_420_SP:
      // This format has never been seen in the wild, but is compatible as we only care
      // about the Y channel, so allow it.
      case PixelFormat.YCbCr_422_SP:
        return new PlanarYUVLuminanceSource(data, width, height, rect.left, rect.top,
            rect.width(), rect.height());
      default:
        // The Samsung Moment incorrectly uses this variant instead of the 'sp' version.
        // Fortunately, it too has all the Y data up front, so we can read it.
        if ("yuv420p".equals(previewFormatString)) {
          return new PlanarYUVLuminanceSource(data, width, height, rect.left, rect.top,
            rect.width(), rect.height());
        }
    }
    throw new IllegalArgumentException("Unsupported picture format: " +
        previewFormat + '/' + previewFormatString);
  }

    public Context getContext() {
        return context;
    }

接下来我们就看看扫描界面的操作了

首先看一下扫描界面，看了之后要做的东西，一目了然了

camera.xml:

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

    <SurfaceView
        android:id="@+id/preview_view"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center" />

    <com.wangy.mycode.Zxing.view.ViewfinderView
        android:id="@+id/viewfinder_view"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
    <RelativeLayout
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_gravity="center"
        android:orientation="vertical" >

        <TextView
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_alignParentTop="true"
            android:layout_centerInParent="true"
            android:background="#038cf7"
            android:gravity="center"
            android:paddingBottom="10dp"
            android:paddingTop="10dp"
            android:text="二维码扫描"
            android:textColor="@android:color/white"
            android:textSize="18sp"
            android:textStyle="bold" />
        <ImageView
            android:id="@+id/result_back"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@drawable/icon_back"
            android:layout_margin="10dp"
            android:layout_alignParentLeft="true"
            />
        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:minHeight="60dp"
            android:text="将取景框对准二维码，
即可自动扫描。"
            android:textColor="#fff"
            android:gravity="center"
            android:textSize="16sp"
            android:layout_above="@+id/ll_type"
            />
        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="200dp"
            android:layout_alignParentRight="true"
            android:gravity="center"
            android:orientation="vertical">
            <TextView
                android:id="@+id/btn_shine"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_margin="10dp"
                android:padding="5dp"
                android:background="@drawable/white"
                android:text="照明"
                android:textColor="#fff"
                android:textSize="15sp"
                />
        </LinearLayout>

        <LinearLayout
            android:id="@+id/ll_type"
            android:layout_width="match_parent"
            android:layout_marginTop="10dp"
            android:layout_alignParentBottom="true"
            android:gravity="center"
            android:layout_height="wrap_content">
        <Button
            android:id="@+id/btn_scan"
            android:layout_width="70dp"
            android:layout_height="70dp"
            android:layout_margin="20dp"
            android:background="@drawable/blueroll"
            android:layout_alignParentBottom="true"
            android:layout_marginBottom="75dp"
            android:text="扫码"
            android:textColor="#fff"
            android:textSize="15sp"
             />
        <Button
            android:id="@+id/btn_phone"
            android:layout_width="70dp"
            android:layout_height="70dp"
            android:layout_margin="20dp"
            android:background="@drawable/tranroll"
            android:layout_alignParentBottom="true"
            android:layout_marginBottom="75dp"
            android:text="相册"
            android:textColor="#fff"
            android:textSize="15sp"
            />
        </LinearLayout>
    </RelativeLayout>

</FrameLayout>

看看扫描界面吧！

package com.wangy.mycode.Zxing;

import android.content.Intent;
import android.content.res.AssetFileDescriptor;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Color;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.os.Handler;
import android.os.Vibrator;
import android.provider.MediaStore;
import android.view.KeyEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.DecodeHintType;
import com.google.zxing.Result;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.QRCodeReader;
import com.wangy.mycode.Base.BaseActivity;
import com.wangy.mycode.R;
import com.wangy.mycode.RGBLuminanceSource;
import com.wangy.mycode.ScanResultActivity;
import com.wangy.mycode.Zxing.camera.CameraManager;
import com.wangy.mycode.Zxing.decoding.CaptureActivityHandler;
import com.wangy.mycode.Zxing.decoding.InactivityTimer;
import com.wangy.mycode.Zxing.view.ViewfinderView;
import com.wangy.mycode.utils.IntentUtils;

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

/**
 * Created by xhb on 2016/12/28.
 */
public class CaptureActivity extends BaseActivity implements SurfaceHolder.Callback, View.OnClickListener {
    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 ImageView result_back;
    private Button btn_scan;
    private Button btn_phone;
    private static final int CHOOSE_PIC = 0;
    private TextView btn_shine;
    private boolean isopen;

    /**
     * Called when the activity is first created.
     */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.camera);
        //ViewUtil.addTopView(getApplicationContext(), this, R.string.scan_card);
        CameraManager.init(getApplication());
        initview();
        viewfinderView = (ViewfinderView) findViewById(R.id.viewfinder_view);
        hasSurface = false;
        inactivityTimer = new InactivityTimer(this);
    }

    private void initview() {
        result_back = (ImageView) findViewById(R.id.result_back);
        btn_scan = (Button) findViewById(R.id.btn_scan);
        btn_phone = (Button) findViewById(R.id.btn_phone);
        btn_shine = (TextView)findViewById(R.id.btn_shine);
        result_back.setOnClickListener(this);
        btn_scan.setOnClickListener(this);
        btn_phone.setOnClickListener(this);
        btn_shine.setOnClickListener(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();
    }

    /**
     * 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("")) {
            Toast.makeText(CaptureActivity.this, "扫描失败！", Toast.LENGTH_SHORT).show();
        } else {
            Intent intent = new Intent(CaptureActivity.this, ScanResultActivity.class);
            intent.putExtra("result", resultString);
            IntentUtils.enterIntent(CaptureActivity.this, intent);
        }
//        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 MediaPlayer.OnCompletionListener beepListener = new MediaPlayer.OnCompletionListener() {
        public void onCompletion(MediaPlayer mediaPlayer) {
            mediaPlayer.seekTo(0);
        }
    };

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.btn_scan: {
                btn_scan.setBackgroundResource(R.drawable.blueroll);
                btn_phone.setBackgroundResource(R.drawable.tranroll);
                break;
            }
            case R.id.btn_phone: {
                btn_phone.setBackgroundResource(R.drawable.blueroll);
                btn_scan.setBackgroundResource(R.drawable.tranroll);
                //跳转到图片选择界面去选择一张二维码图片
                Intent intent1 = new Intent();
                intent1.setAction(Intent.ACTION_PICK);

                intent1.setType("image/*");

                Intent intent2 = Intent.createChooser(intent1, "选择二维码图片");
                startActivityForResult(intent2, CHOOSE_PIC);
                break;
            }
            case R.id.result_back: {
                overridePendingTransition(R.anim.in_from_left, R.anim.out_to_right);
                finish();
                break;
            }
            case R.id.btn_shine:{
                if (isopen){
                    btn_shine.setTextColor(Color.WHITE);
                    btn_shine.setBackgroundResource(R.drawable.white);
                }else {
                    btn_shine.setTextColor(Color.parseColor("#038cf7"));
                    btn_shine.setBackgroundResource(R.drawable.blue);
                }
                isopen=!isopen;
                //控制开启和关闭闪光灯
                CameraManager.get().flashHandler();
            }
            default: {
                break;
            }
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        String imgPath = null;
        if (resultCode == RESULT_OK) {
            switch (requestCode) {
                case CHOOSE_PIC:
                    try {
                        String[] proj = new String[]{MediaStore.Images.Media.DATA};
                        Cursor cursor = CaptureActivity.this.getContentResolver().query(data.getData(), proj, null, null, null);

                        if (cursor.moveToFirst()) {
                            int columnIndex = cursor.getColumnIndex(MediaStore.Images.Media.DATA);
                            System.out.println(columnIndex);
                            //获取到用户选择的二维码图片的绝对路径
                            imgPath = cursor.getString(columnIndex);
                        }
                        cursor.close();
                        //获取解析结果
                        final String finalImgPath = imgPath;
                        new Thread(new Runnable() {
                            @Override
                            public void run() {
                                Result ret = parseQRcodeBitmap(finalImgPath);
                                Intent intent = new Intent(CaptureActivity.this, ScanResultActivity.class);
                                intent.putExtra("result", ret.toString());
                                IntentUtils.enterIntent(CaptureActivity.this, intent);
                            }
                        }).start();

                    } catch (Exception e) {
                        Toast.makeText(CaptureActivity.this,  "扫描失败", Toast.LENGTH_LONG).show();
                    }

                    break;
            }
        }
    }
    //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
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        if (keyCode == KeyEvent.KEYCODE_BACK) {
            overridePendingTransition(R.anim.in_from_left, R.anim.out_to_right);
            finish();
            return false;
        } else {
            return super.onKeyDown(keyCode, event);
        }
    }
}

好了，扫描之后，肯定也要对扫描结果进行处理，那就看看ScanResultActivity吧

结果的处理，我是参照qq做的，也没啥难的地方，大家可以看看

package com.wangy.mycode;

import android.content.Intent;
import android.os.Bundle;
import android.view.Gravity;
import android.view.KeyEvent;
import android.view.View;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;

import com.wangy.mycode.Base.BaseActivity;
import com.wangy.mycode.Zxing.CaptureActivity;

/**
 * Created by xhb on 2016/12/28.
 */
public class ScanResultActivity extends BaseActivity {

    private ImageView result_back;
    private TextView scanresult_word;
    private WebView scanresult_webview;
    private String result;
    private LinearLayout ll_result_word;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.scanresultlayout);
        Intent intent = getIntent();
        if (intent != null) {
            result = intent.getStringExtra("result");
        }
        initView();
    }

    private void initView() {
        result_back = (ImageView) findViewById(R.id.result_back);
        result_back.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
//                startActivity(new Intent(ScanResultActivity.this,CaptureActivity.class));
//                overridePendingTransition(R.anim.in_from_left, R.anim.out_to_right);
                finish();
            }
        });
        ll_result_word = (LinearLayout)findViewById(R.id.ll_result_word);
        scanresult_word = (TextView) findViewById(R.id.scanresult_word);
        scanresult_webview = (WebView) findViewById(R.id.scanresult_webview);
        if ((result.contains("http://") || result.contains("https://"))) {
            scanresult_webview.setVisibility(View.VISIBLE);
            ll_result_word.setVisibility(View.GONE);
            setScanresult_webview();
        }else {
            scanresult_webview.setVisibility(View.GONE);
            ll_result_word.setVisibility(View.VISIBLE);
            scanresult_word.setText(result);
        }

    }
private void setScanresult_webview(){
    if ((result.contains("http://") || result.contains("https://"))) {
        //加载需要显示的网页
        scanresult_webview.loadUrl(result);
    }

    //覆盖WebView默认使用第三方或系统默认浏览器打开网页的行为，使网页用WebView打开
    scanresult_webview.setWebViewClient(new WebViewClient() {
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            // TODO Auto-generated method stub
            //返回值是true的时候控制去WebView打开，为false调用系统浏览器或第三方浏览器
            view.loadUrl(url);
            return true;
        }
    });
    WebSettings webSettings = scanresult_webview.getSettings();
    //设置可以访问文件
    webSettings.setAllowFileAccess(true);
    webSettings.setJavaScriptEnabled(true);//支持js
    webSettings.setJavaScriptCanOpenWindowsAutomatically(true);
    webSettings.setDomStorageEnabled(true);
    //设置支持缩放
    webSettings.setBuiltInZoomControls(true);
   // 优先使用缓存
    scanresult_webview.getSettings().setCacheMode(WebSettings.LOAD_CACHE_ELSE_NETWORK);
    scanresult_webview.setWebChromeClient(new WebChromeClient() {
        @Override
        public void onProgressChanged(WebView view, int newProgress) {
            // TODO Auto-generated method stub
            if (newProgress == 100) {
                // 网页加载完成
                showCustomToast("网页加载完成");
            } else {
                // 加载中
//                showCustomToast("网页加载中...");
            }

        }
    });
//    scanresult_webview.setDownloadListener(new DownloadListener() {
//        @Override
//        public void onDownloadStart(String s, String s1, String s2, String s3, long l) {
//            String html = "<a href='" + s + "'>" + s + "</a>";
//            scanresult_webview.loadData(html, "text/html", "UTF-8");
//        }
//    });


}
    //弹出警告框
    public void showCustomToast(String text) {
        Toast toast = Toast.makeText(ScanResultActivity.this,
                text, Toast.LENGTH_SHORT);
        toast.setGravity(Gravity.CENTER, 20, 20);
        LinearLayout toastView = (LinearLayout) toast.getView();
        ImageView imageCodeProject = new ImageView(ScanResultActivity.this);
        imageCodeProject.setImageResource(R.drawable.ico_warning);
        toastView.addView(imageCodeProject, 0);
        toastView.setPadding(100, 85, 100, 85);
        toast.show();
    }

//    返回上一次浏览的页面

    //改写物理按键——返回的逻辑
    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        // TODO Auto-generated method stub
        if(keyCode==KeyEvent.KEYCODE_BACK)
        {
            if(scanresult_webview.canGoBack())
            {
                scanresult_webview.goBack();//返回上一页面
                return true;
            }
            else
            {
//                startActivity(new Intent(ScanResultActivity.this,CaptureActivity.class));
//                overridePendingTransition(R.anim.in_from_left, R.anim.out_to_right);
                finish();
                return false;
            }
        }
        return super.onKeyDown(keyCode, event);
    }
}

界面也给大家看看

scanresultlayout

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">
    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:minHeight="50dp"
        android:background="#038cf7"
        >
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:text="二维码扫描结果"
            android:textSize="18sp"
            android:textColor="#fff"
            />
        <ImageView
            android:id="@+id/result_back"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@drawable/icon_back"
            android:layout_margin="10dp"
            android:layout_centerVertical="true"
            android:layout_alignParentLeft="true"
            />
    </RelativeLayout>
    <LinearLayout
        android:id="@+id/ll_result_word"
        android:layout_width="match_parent"
        android:orientation="vertical"
        android:visibility="gone"
        android:layout_height="wrap_content">
   <TextView
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
      android:layout_marginTop="30dp"
       android:textColor="#e78727"
       android:text="以下内容非本app提供，请谨慎使用"
       android:gravity="center"
       />
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="5dp"
        android:text="如需使用请复制"
        android:textColor="#e78727"
        android:gravity="center"
        />

    <TextView
        android:id="@+id/scanresult_word"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:minWidth="300dp"
        android:minHeight="100dp"
        android:background="@drawable/yellow"
        android:layout_marginTop="50dp"
        android:layout_gravity="center_horizontal"
        android:text="如需使用请复制"
        android:textColor="#f5262121"
        android:textStyle="normal"
        android:gravity="center"
        />
    </LinearLayout>

    <WebView
        android:id="@+id/scanresult_webview"
        android:layout_width="match_parent"
        android:visibility="gone"
        android:layout_height="match_parent">

    </WebView>
</LinearLayout>

就简单介绍到这里吧！我做的app源码地址，有需要的可以看看，参照写一下

下载地址： http://download.csdn.net/detail/sinat_32804317/9725715