生成二维码图片(android)
一、在项目app的build.gradle里添加Zxing依赖库；
implementation 'com.google.zxing:core:3.3.0'
二、编写一个生成二维码的工具类
public class CreatQrCodeUtil {
//生成普通二维码bitmap，中心不带logo图片
public static Bitmap CreatEwmImg(String QrCodeMsg) {
Bitmap bitmap=null;
BitMatrix result=null;
MultiFormatWriter multiFormatWriter=new MultiFormatWriter();
try {
result=multiFormatWriter.encode(QrCodeMsg,BarcodeFormat.QR_CODE,800,800);//800,800 为设定的bitmap宽高，可根据需求更改
int w=result.getWidth();
int h=result.getHeight();
int[] pixels=new int[w*h]; //像素值
for (int y = 0; y < h; y++) {
int offset=y*w;
for (int x = 0; x
}
}
bitmap=Bitmap.createBitmap(w,h,Bitmap.Config.ARGB_8888);//固定色值，设置8888
bitmap.setPixels(pixels,0,w,0,0,w,h);
} catch (Exception e) {
e.printStackTrace();
}
return bitmap;
}
//生成中心带logo图案的二维码图片(bitmap)
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
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.restore();
} catch (Exception e) {
bitmap = null;
e.getStackTrace();
}
return bitmap;
}
}
三、用法
用ImageView的 setImageBitmap() 方法加载工具类生成的bitmap格式图片，eg:
//生成普通二维码bitmap，中心不带logo图片
Bitmap bm = CreatQrCodeUtil.CreatEwmImg("MrHao：二维码图片生成");
ImageView.setImageBitmap(bm);
//生成中心带logo图案的二维码图片
Bitmap bm = CreatQrCodeUtil.CreateQrCode("MrHao：二维码图片生成", 600, 600, bitmap);
ImageView.setImageBitmap(bm);
