Android 带logo的二维码详解及实例

<RelativeLayout xmlns:Android="http://schemas.android.com/apk/res/android"  xmlns:tools="http://schemas.android.com/tools"  android:layout_width="match_parent"  android:layout_height="match_parent"  android:paddingBottom="@dimen/activity_vertical_margin"  android:paddingLeft="@dimen/activity_horizontal_margin"  android:paddingRight="@dimen/activity_horizontal_margin"  android:paddingTop="@dimen/activity_vertical_margin"  tools:context="com.example.MainActivity" >  <ImageView    android:id="@+id/code"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:layout_centerInParent="true"    android:text="@string/hello_world" /></RelativeLayout>

package com.example;import Java.util.Hashtable;import android.app.Activity;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.os.Bundle;import android.widget.ImageView;import com.google.zxing.BarcodeFormat;import com.google.zxing.EncodeHintType;import com.google.zxing.WriterException;import com.google.zxing.common.BitMatrix;import com.google.zxing.qrcode.QRCodeWriter;public class MainActivity extends Activity {  private ImageView code;  private final int QR_WIDTH=300;  private final int QR_HEIGHT=300; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); code=(ImageView) findViewById(R.id.code); createImage("weixin") ; } // 生成QR图  private void createImage(String text) {    try {      // 需要引入core包      QRCodeWriter writer = new QRCodeWriter();      // 把输入的文本转为二维码      BitMatrix martix = writer.encode(text, BarcodeFormat.QR_CODE,          QR_WIDTH, QR_HEIGHT);     //图像数据转换，使用了矩阵转换    Hashtable<EncodeHintType, String> hints = new Hashtable<EncodeHintType, String>();      hints.put(EncodeHintType.CHARACTER_SET, "utf-8");      BitMatrix bitMatrix = new QRCodeWriter().encode(text,          BarcodeFormat.QR_CODE, QR_WIDTH, QR_HEIGHT, hints);      int[] pixels = new int[QR_WIDTH * QR_HEIGHT];      for (int y = 0; y < QR_HEIGHT; y++) {//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 x = 0; x < QR_WIDTH; x++) {          if (bitMatrix.get(x, y)) {            pixels[y * QR_WIDTH + x] = 0xff000000;//黑色          } else {            pixels[y * QR_WIDTH + x] = 0xffffffff;//白色          }        }      }   //------------------添加图片部分------------------//  Bitmap logoBmp = BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);      Bitmap bitmap = Bitmap.createBitmap(QR_WIDTH, QR_HEIGHT,          Bitmap.Config.ARGB_8888);//设置像素点      bitmap.setPixels(pixels, 0, QR_WIDTH, 0, 0, QR_WIDTH, QR_HEIGHT);            Canvas canvas = new Canvas(bitmap);     //二维码     canvas.drawBitmap(bitmap, 0,0, null);     //图片绘制在二维码中央，合成二维码图片  canvas.drawBitmap(logoBmp, bitmap.getWidth() / 2   - logoBmp.getWidth() / 2, bitmap.getHeight()   / 2 - logoBmp.getHeight() / 2, null);  //------------------添加logo部分------------------//      code.setImageBitmap(bitmap);         } catch (WriterException e) {      e.printStackTrace();    }  } }