我在我的应用程序ZXing库中使用它来生成QR码.我想生成适合屏幕宽度的QR码(可能是一些小填充).
如果我将屏幕宽度设置为QR码的宽度尺寸,我会得到更小的QR码.看截图(它是320×240分辨率).我想要QR码适合黑色区域.为什么QR码红色这么小?
如何将其拉伸到黑色区域?
我的代码:
Display display = getWindowManager().getDefaultDisplay(); Point size = new Point(); display.getSize(size); int width = size.x; Bitmap bm = encodeAsBitmap(mGeneratedURL,BarcodeFormat.QR_CODE,width,width); qrcodeImage.setImageBitmap(bm);
生成QR码:
private Bitmap encodeAsBitmap(String contents,BarcodeFormat format,int img_width,int img_height) throws WriterException { String contentsToEncode = contents; if (contentsToEncode == null) { return null; } Map<EncodeHintType,Object> hints = null; String encoding = guessAppropriateEncoding(contentsToEncode); if (encoding != null) { hints = new EnumMap<EncodeHintType,Object>(EncodeHintType.class); //hints.put(EncodeHintType.CHARACTER_SET,encoding); hints.put(EncodeHintType.MARGIN,0); /* default = 4 */ } MultiFormatWriter writer = new MultiFormatWriter(); BitMatrix result; try { result = writer.encode(contentsToEncode,format,img_width,img_height,hints); } catch (IllegalArgumentException iae) { // Unsupported format return null; } int width = result.getWidth(); int height = result.getHeight(); int[] pixels = new int[width * height]; 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) ? RED : Color.BLACK; } } Bitmap bitmap = Bitmap.createBitmap(width,height,Bitmap.Config.ARGB_8888); bitmap.setPixels(pixels,height); return bitmap; }
解决方法
我发现了一个问题!
这一行:
String encoding = guessAppropriateEncoding(contentsToEncode);
返回null
所以它没有设定
EncodeHintType.MARGIN.
//if (encoding != null) { hints = new EnumMap<EncodeHintType,Object>(EncodeHintType.class); //hints.put(EncodeHintType.CHARACTER_SET,encoding); hints.put(EncodeHintType.MARGIN,0); /* default = 4 */ //}