Android Zxing库里的ViewfinderView实例化的问题

下面的是代码，查了好多资料都找不出这个无法实例化的原因，求大佬帮忙解答一下。

package com.zxing.view;

import java.util.Collection;
import java.util.HashSet;

import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.view.View;

import com.ericssonlabs.R;
import com.google.zxing.ResultPoint;
import com.zxing.camera.CameraManager;

/**

• This view is overlaid on top of the camera preview. It adds the viewfinder rectangle and partial
• transparency outside it, as well as the laser scanner animation and result points.

• 锟皆讹拷锟斤拷锟絍iew锟斤拷锟斤拷锟斤拷时锟叫硷拷锟斤拷示锟斤拷
  */
  public final class ViewfinderView extends View {

  private static final int[] SCANNER_ALPHA = {0, 64, 128, 192, 255, 192, 128, 64};
  private static final long ANIMATION_DELAY = 100L;
  private static final int OPAQUE = 0xFF;

  private final Paint paint;
  private Bitmap resultBitmap;
  private final int maskColor;
  private final int resultColor;
  private final int frameColor;
  private final int laserColor;
  private final int resultPointColor;
  private int scannerAlpha;
  private Collection possibleResultPoints;
  private Collection lastPossibleResultPoints;

  // This constructor is used when the class is built from an XML resource.
  public ViewfinderView(Context context, AttributeSet attrs) {
  super(context, attrs);

  // Initialize these once for performance rather than calling them every time in onDraw().
  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);
  laserColor = resources.getColor(R.color.viewfinder_laser);
  resultPointColor = resources.getColor(R.color.possible_result_points);
  scannerAlpha = 0;
  possibleResultPoints = new HashSet(5);
  }

  @Override
  public void onDraw(Canvas canvas) {
  Rect frame = CameraManager.get().getFramingRect();
  if (frame == null) {
  return;
  }
  int width = canvas.getWidth();
  int height = canvas.getHeight();

  // Draw the exterior (i.e. outside the framing rect) darkened
  paint.setColor(resultBitmap != null ? resultColor : maskColor);
  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 {

  // Draw a two pixel solid black border inside the framing rect
  paint.setColor(frameColor);
  canvas.drawRect(frame.left, frame.top, frame.right + 1, frame.top + 2, paint);
  canvas.drawRect(frame.left, frame.top + 2, frame.left + 2, frame.bottom - 1, paint);
  canvas.drawRect(frame.right - 1, frame.top, frame.right + 1, frame.bottom - 1, paint);
  canvas.drawRect(frame.left, frame.bottom - 1, frame.right + 1, frame.bottom + 1, paint);

  // Draw a red "laser scanner" line through the middle to show decoding is active
  paint.setColor(laserColor);
  paint.setAlpha(SCANNER_ALPHA[scannerAlpha]);
  scannerAlpha = (scannerAlpha + 1) % SCANNER_ALPHA.length;
  int middle = frame.height() / 2 + frame.top;
  canvas.drawRect(frame.left + 2, middle - 1, frame.right - 1, middle + 2, 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);
  }
  }

  // Request another update at the animation interval, but only repaint the laser line,
  // not the entire viewfinder mask.
  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);
  }

}

https://blog.csdn.net/AdrianAndroid/article/details/71544665