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 */
- //}