content: package com.google.zxing.encoding;
  
  import android.graphics.Bitmap;
  import android.graphics.Canvas;
  
  import com.google.zxing.BarcodeFormat;
  import com.google.zxing.EncodeHintType;
  import com.google.zxing.MultiFormatWriter;
  import com.google.zxing.WriterException;
  import com.google.zxing.common.BitMatrix;
  import com.google.zxing.qrcode.QRCodeWriter;
  import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
  
  import java.util.HashMap;
  import java.util.Hashtable;
  import java.util.Map;
  
  /**
   * @author Ryan Tang
   *
   */
  public final class EncodingHandler {
  	private static final int BLACK = 0xff000000;
  	
  	public static Bitmap createQRCode(String str, int widthAndHeight) throws WriterException {
  		Hashtable<EncodeHintType, String> hints = new Hashtable<EncodeHintType, String>();
          hints.put(EncodeHintType.CHARACTER_SET, "utf-8"); 
  		BitMatrix matrix = new MultiFormatWriter().encode(str,
  				BarcodeFormat.QR_CODE, widthAndHeight, widthAndHeight);
  		int width = matrix.getWidth();
  		int height = matrix.getHeight();
  		int[] pixels = new int[width * height];
  		
  		for (int y = 0; y < height; y++) {
  			for (int x = 0; x < width; x++) {
  				if (matrix.get(x, y)) {
  					pixels[y * width + x] = BLACK;
  				}
  			}
  		}
  		Bitmap bitmap = Bitmap.createBitmap(width, height,
  				Bitmap.Config.ARGB_8888);
  		bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
  		return bitmap;
  	}
  	
  	/**
  	 * 创建二维码
  	 *
  	 * @param content   content
  	 * @param widthPix  widthPix
  	 * @param heightPix heightPix
  	 * @param logoBm    logoBm
  	 * @return 二维码
  	 */
  	public static Bitmap createQRCode(String content, int widthPix, int heightPix, Bitmap logoBm) {
  		try {
  			if (content == null || "".equals(content)) {
  				return null;
  			}
  			// 配置参数
  			Map<EncodeHintType, Object> hints = new HashMap<>();
  			hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
  			// 容错级别
  			hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
  			// 图像数据转换，使用了矩阵转换
  			BitMatrix bitMatrix = new QRCodeWriter().encode(content, BarcodeFormat.QR_CODE, widthPix,
  					heightPix, hints);
  			int[] pixels = new int[widthPix * heightPix];
  			// 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 < heightPix; y++) {
  				for (int x = 0; x < widthPix; x++) {
  					if (bitMatrix.get(x, y)) {
  						pixels[y * widthPix + x] = 0xff000000;
  					} else {
  						pixels[y * widthPix + x] = 0xffffffff;
  					}
  				}
  			}
  			// 生成二维码图片的格式，使用ARGB_8888
  			Bitmap bitmap = Bitmap.createBitmap(widthPix, heightPix, Bitmap.Config.ARGB_8888);
  			bitmap.setPixels(pixels, 0, widthPix, 0, 0, widthPix, heightPix);
  			if (logoBm != null) {
  				bitmap = addLogo(bitmap, logoBm);
  			}
  			//必须使用compress方法将bitmap保存到文件中再进行读取。直接返回的bitmap是没有任何压缩的，内存消耗巨大！
  			return bitmap;
  		} catch (WriterException e) {
  			e.printStackTrace();
  		}
  		return null;
  	}
  
  	/**
  	 * 在二维码中间添加Logo图案
  	 */
  	private static Bitmap addLogo(Bitmap src, Bitmap logo) {
  		if (src == null) {
  			return null;
  		}
  		if (logo == null) {
  			return src;
  		}
  		//获取图片的宽高
  		int srcWidth = src.getWidth();
  		int srcHeight = src.getHeight();
  		int logoWidth = logo.getWidth();
  		int logoHeight = logo.getHeight();
  		if (srcWidth == 0 || srcHeight == 0) {
  			return null;
  		}
  		if (logoWidth == 0 || logoHeight == 0) {
  			return src;
  		}
  		//logo大小为二维码整体大小的1/5
  		float scaleFactor = srcWidth * 1.0f / 5 / logoWidth;
  		Bitmap bitmap = Bitmap.createBitmap(srcWidth, srcHeight, Bitmap.Config.ARGB_8888);
  		try {
  			Canvas canvas = new Canvas(bitmap);
  			canvas.drawBitmap(src, 0, 0, null);
  			canvas.scale(scaleFactor, scaleFactor, srcWidth / 2, srcHeight / 2);
  			canvas.drawBitmap(logo, (srcWidth - logoWidth) / 2, (srcHeight - logoHeight) / 2, null);
  			canvas.save(Canvas.ALL_SAVE_FLAG);
  			canvas.restore();
  		} catch (Exception e) {
  			bitmap = null;
  			e.getStackTrace();
  		}
  		return bitmap;
  	}
  }
  