How to create bar code image from text and scan code in android ?
To create this app we use the zxing library of QRcode scanning.
put the following line in gradle dependency in android studio.
dependencies {
compile 'com.journeyapps:zxing-android-embedded:3.0.2@aar' compile 'com.google.zxing:core:3.2.0'
}
Then sync your project. In your activity oncreate() create an EditText to take input and a
button for generate barcode image and an Imageview for displaying barcode.
@Override
protected void onCreate(Bundle savedInstanceState) {
btnCreateBarcode = (Button) findViewById(R.id.btnCreateBarcode);
btnQrCoderScanner = (Button) findViewById(R.id.btnQrCoderScanner);
imageView = (ImageView) findViewById(R.id.imageView);
tv = (TextView) findViewById(R.id.textView);
input = (EditText) findViewById(R.id.input);
btnCreateBarcode.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
barcode_data = input.getText().toString();
Bitmap bitmap = null;
try {
bitmap = encodeAsBitmap(barcode_data, BarcodeFormat.CODE_128, 300, 150);
imageView.setImageBitmap(bitmap);
} catch (WriterException e) {
e.printStackTrace();
}
tv.setText(barcode_data);
}
});
}
private static final int WHITE = 0xFFFFFFFF;
private static final int BLACK = 0xFF000000;
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);
}
MultiFormatWriter writer = new MultiFormatWriter();
BitMatrix result;
try {
result = writer.encode(contentsToEncode, format, img_width, img_height, hints);
} catch (IllegalArgumentException iae) {
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) ? BLACK : WHITE;
}
}
Bitmap bitmap = Bitmap.createBitmap(width, height,
Bitmap.Config.ARGB_8888);
bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
return bitmap;
}
private static String guessAppropriateEncoding(CharSequence contents) {
for (int i = 0; i < contents.length(); i++) {
if (contents.charAt(i) > 0xFF) {
return "UTF-8";
}
}
return null;
}
If you want to scan barcode or qrcode then just add another button and add action to it like -
btnQrCoderScanner.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
IntentIntegrator integrator = new IntentIntegrator(MainActivity.this);
integrator.initiateScan();
}
});
The IntentIntegrator will give a result back So on onActivityResult() catch the scan result .
public void onActivityResult(int requestCode, int resultCode, Intent data) {
IntentResult scanResult = IntentIntegrator.parseActivityResult(requestCode, resultCode, data);
if (scanResult != null) {
Toast.makeText(this, scanResult.getContents(), Toast.LENGTH_SHORT).show();
}
}
