1.android 有自带的jar包可以生成二维码core-3.0.0.jar，其中的com.google.zxing包
2.写一个二维码生成的工具类，网上搜的话应该一大堆。
package com.example.administrator.twocodedemo;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.PointF;
import android.view.Gravity;
import android.view.View.MeasureSpec;
import android.widget.LinearLayout;
import android.widget.LinearLayout.LayoutParams;
import android.widget.TextView;
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 java.util.Hashtable;
/**
*
* 生成条形码和二维码的工具
*/
public class ZXingUtils {
/**
* 生成二维码 要转换的地址或字符串,可以是中文
*
* @param url
* @param width
* @param height
* @return
*/
public static Bitmap createQRImage(String url, final int width, final int height) {
try {
// 判断URL合法性
if (url == null || "".equals(url) || url.length() < 1) {
return null;
}
Hashtable hints = new Hashtable();
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(url,
BarcodeFormat.QR_CODE, width, height, hints);
int[] pixels = new int[width * 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 < height; y++) {
for (int x = 0; x < width; x++) {
if (bitMatrix.get(x, y)) {
pixels[y * width + x] = 0xff000000;
} else {
pixels[y * width + x] = 0xffffffff;
}
}
}
// 生成二维码图片的格式，使用ARGB_8888
Bitmap bitmap = Bitmap.createBitmap(width, height,
Bitmap.Config.ARGB_8888);
bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
return bitmap;
} catch (WriterException e) {
e.printStackTrace();
}
return null;
}
/**
* 生成条形码
*
* @param context
* @param contents
* 需要生成的内容
* @param desiredWidth
* 生成条形码的宽带
* @param desiredHeight
* 生成条形码的高度
* @param displayCode
* 是否在条形码下方显示内容
* @return
*/
public static Bitmap creatBarcode(Context context, String contents,
int desiredWidth, int desiredHeight, boolean displayCode) {
Bitmap ruseltBitmap = null;
/**
* 图片两端所保留的空白的宽度
*/
int marginW = 20;
/**
* 条形码的编码类型
*/
BarcodeFormat barcodeFormat = BarcodeFormat.CODE_128;
if (displayCode) {
Bitmap barcodeBitmap = encodeAsBitmap(contents, barcodeFormat,
desiredWidth, desiredHeight);
Bitmap codeBitmap = creatCodeBitmap(contents, desiredWidth + 2
* marginW, desiredHeight, context);
ruseltBitmap = mixtureBitmap(barcodeBitmap, codeBitmap, new PointF(
0, desiredHeight));
} else {
ruseltBitmap = encodeAsBitmap(contents, barcodeFormat,
desiredWidth, desiredHeight);
}
return ruseltBitmap;
}
/**
* 生成条形码的Bitmap
*
* @param contents
* 需要生成的内容
* @param format
* 编码格式
* @param desiredWidth
* @param desiredHeight
* @return
* @throws WriterException
*/
protected static Bitmap encodeAsBitmap(String contents,
BarcodeFormat format, int desiredWidth, int desiredHeight) {
final int WHITE = 0xFFFFFFFF;
final int BLACK = 0xFF000000;
MultiFormatWriter writer = new MultiFormatWriter();
BitMatrix result = null;
try {
result = writer.encode(contents, format, desiredWidth,
desiredHeight, null);
} catch (WriterException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
int width = result.getWidth();
int height = result.getHeight();
int[] pixels = new int[width * height];
// All are 0, or black, by default
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;
}
/**
* 生成显示编码的Bitmap
*
* @param contents
* @param width
* @param height
* @param context
* @return
*/
protected static Bitmap creatCodeBitmap(String contents, int width,
int height, Context context) {
TextView tv = new TextView(context);
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(
LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
tv.setLayoutParams(layoutParams);
tv.setText(contents);
tv.setHeight(height);
tv.setGravity(Gravity.CENTER_HORIZONTAL);
tv.setWidth(width);
tv.setDrawingCacheEnabled(true);
tv.setTextColor(Color.BLACK);
tv.measure(MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED),
MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
tv.layout(0, 0, tv.getMeasuredWidth(), tv.getMeasuredHeight());
tv.buildDrawingCache();
Bitmap bitmapCode = tv.getDrawingCache();
return bitmapCode;
}
/**
* 将两个Bitmap合并成一个
*
* @param first
* @param second
* @param fromPoint
* 第二个Bitmap开始绘制的起始位置（相对于第一个Bitmap）
* @return
*/
protected static Bitmap mixtureBitmap(Bitmap first, Bitmap second,
PointF fromPoint) {
if (first == null || second == null || fromPoint == null) {
return null;
}
int marginW = 20;
Bitmap newBitmap = Bitmap.createBitmap(
first.getWidth() + second.getWidth() + marginW,
first.getHeight() + second.getHeight(), Config.ARGB_4444);
Canvas cv = new Canvas(newBitmap);
cv.drawBitmap(first, marginW, 0, null);
cv.drawBitmap(second, fromPoint.x, fromPoint.y, null);
cv.save(Canvas.ALL_SAVE_FLAG);
cv.restore();
return newBitmap;
}
} 准备工作完成，现在可以在用到的地方使用，我们这里就在MainActivity中
package com.example.administrator.twocodedemo;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import butterknife.BindView;
import butterknife.ButterKnife;
import butterknife.OnClick;
public class MainActivity extends AppCompatActivity {
@BindView(R.id.et_url)
EditText etUrl;
@BindView(R.id.btn_create)
Button btnCreate;
@BindView(R.id.iv_two_code)
ImageView ivTwoCode;
private String imagePath;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ButterKnife.bind(this);
}
@OnClick({R.id.btn_create, R.id.iv_two_code})
public void onClick(View view) {
switch (view.getId()) {
case R.id.btn_create:
String url = etUrl.getText().toString().trim();
Bitmap bitmap = ZXingUtils.createQRImage(url, ivTwoCode.getWidth(), ivTwoCode.getHeight());
ivTwoCode.setImageBitmap(bitmap); 这其中使用了Butterknife注解工具，其中真正的代码就两句：
Bitmap bitmap = ZXingUtils.createQRImage(url, ivTwoCode.getWidth(), ivTwoCode.getHeight());
ivTwoCode.setImageBitmap(bitmap); 