android - 如何使用Zxing Library生成二维码？

Question

我正在尝试为我的应用程序生成二维码。用户将输入一些文本，数据将传递给下一个显示二维码的 Activity 。

这是我的代码。

public class QRgenerator extends AppCompatActivity {

ImageView imageView;
String Qrcode;
public static final int WIDTH = 500;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_qrgenerator);

    getID();

    Intent intent = getIntent();
    Qrcode = intent.getStringExtra("Data");


    //creating thread to avoid ANR exception
    Thread t = new Thread(new Runnable() {
        @Override
        public void run() {
            //the message to be encoded in the qr code.


            try {
                synchronized (this) {
                    wait(5000);

                    //runonUIthread on the main thread
                    runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            try {
                                Bitmap bitmap = null;

                                bitmap = encodeasBitmap(Qrcode);
                                imageView.setImageBitmap(bitmap);
                            } catch (WriterException e) {
                                e.printStackTrace();
                                ;
                            } //end of catch block
                        } //end of rum method
                    });
                }
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    });
    t.start();
}

//method that returns the bitmap image of the QRcode.
public void getID() {
    imageView = (ImageView) findViewById(R.id.imageView2);
}

public Bitmap encodeasBitmap(String str) throws WriterException {

    BitMatrix result;
    try {
        result = new MultiFormatWriter().encode(str, BarcodeFormat.QR_CODE, WIDTH, WIDTH, null);
    } catch (IllegalArgumentException e) {
        //unsupported format
        return null;
    }
    int h = result.getHeight();
    int w = result.getWidth();

    int[] pixels = new int[w * h];

    for (int i = 0; i < h; i++) {
        int offset = i * w;
        for (int j = 0; j < w; j++) {
            pixels[offset + j] = result.get(j, i)? R.color.black:R.color.white;
        }
    }
    Bitmap bitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
    bitmap.setPixels(pixels, 0, 500, 0, 0, w, h);
    return bitmap;
}
}

问题是当我按下按钮并转到下一个屏幕时，只出现白色屏幕， ImageView 中也没有 QR 码。可能是什么错误？

Answer 1

 public static Bitmap generateQRBitmap(String content, Context context,int flag){
    Bitmap bitmap = null;
    int width=256,height=256;

    QRCodeWriter writer = new QRCodeWriter();
    try {
        BitMatrix bitMatrix = writer.encode(content, BarcodeFormat.QR_CODE, width, height);//256, 256
       /* int width = bitMatrix.getWidth();
        int height = bitMatrix.getHeight();*/
        bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.RGB_565);
        for (int x = 0; x < width; x++) {
            for (int y = 0; y < height; y++) {
                //bitmap.setPixel(x, y, bitMatrix.get(x, y) ? Color.BLACK : Color.WHITE);//guest_pass_background_color
                bitmap.setPixel(x, y, bitMatrix.get(x, y) ? Color.BLACK : context.getResources().getColor(R.color.guest_pass_background_color));//Color.WHITE
            }
        }
    } catch (WriterException e) {
        e.printStackTrace();
    }
    return bitmap;
}