QRCodeGenerateActivity.java

package jp.mydns.sys1yagi.android.zxingsample;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.EditText;
import android.widget.ImageView;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;

public class QRCodeGenerateActivity extends Activity {

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

        findViewById(R.id.generate_button).setOnClickListener(
                new OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        EditText editText = (EditText) findViewById(R.id.code_content);
                        Bitmap qrcode = generateQRCode(editText.getText()
                                .toString());
                        ImageView imageView = (ImageView) findViewById(R.id.code_image);
                        imageView.setImageBitmap(qrcode);
                    }
                });

    }

    private Bitmap bitMatrix2Bitmap(BitMatrix matrix) {
        int w = matrix.getWidth();
        int h = matrix.getHeight();
        int[] rawData = new int[w * h];
        for (int i = 0; i < w; i++) {
            for (int j = 0; j < h; j++) {
                int color = Color.WHITE;
                if (matrix.get(i, j)) {
                    color = Color.BLACK;
                }
                rawData[i + (j * w)] = color;
            }
        }

        Bitmap bitmap = Bitmap.createBitmap(w, h, Config.RGB_565);
        bitmap.setPixels(rawData, 0, w, 0, 0, w, h);
        return bitmap;
    }

    private Bitmap generateQRCode(String content) {
        try {
            MultiFormatWriter writer = new MultiFormatWriter();
            BitMatrix matrix = writer.encode(content, BarcodeFormat.QR_CODE,
                    500, 500);
            return bitMatrix2Bitmap(matrix);
        } catch (WriterException e) {
            e.printStackTrace();
        }
        return null;
    }
}