Dart Requires Chilkat v11.7.0+

Choose the QR Code Version and Mask Pattern

See more QR Code Examples

Demonstrates fixing the QR version and the mask pattern. The version (1 to 40) is the size of the symbol: version 1 is 21 modules wide and each version adds 4. By default QrCode picks the smallest version that holds the data and the mask pattern that scores best under the QR standard. Fixing the version is useful when a series of codes must all be the same size, and minVersion and maxVersion bound the automatic choice instead. Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // This example requires the Chilkat API to have been previously unlocked.
  // See Global Unlock Sample for sample code.

  final fmt = CkFormats();
  final json = CkJsonObject();
  final jsonOut = CkJsonObject();
  json.updateString('payload.text', 'https://www.chilkatsoft.com/');

  // Automatic: the smallest version that holds the text, and the best-scoring mask.
  try {
    fmt.qrCode('generate', json, jsonOut);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print('automatic: version ${jsonOut.intOf('symbols[0].selectedEncoding.version')}, ${jsonOut.intOf('symbols[0].dimensions.modulesWide')} modules wide, mask ${jsonOut.intOf('symbols[0].selectedEncoding.mask')}');

  // A fixed version.  The call fails with capacityExceeded if the text does not fit it.
  json.updateInt('encoding.qr.version', 8);
  try {
    fmt.qrCode('generate', json, jsonOut);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print('version 8: version ${jsonOut.intOf('symbols[0].selectedEncoding.version')}, ${jsonOut.intOf('symbols[0].dimensions.modulesWide')} modules wide, mask ${jsonOut.intOf('symbols[0].selectedEncoding.mask')}');

  // A fixed mask pattern, 0 to 7.  Every mask gives a valid symbol holding the same data.
  json.updateInt('encoding.qr.mask', 5);
  try {
    fmt.qrCode('generate', json, jsonOut);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print('version 8, mask 5: version ${jsonOut.intOf('symbols[0].selectedEncoding.version')}, mask ${jsonOut.intOf('symbols[0].selectedEncoding.mask')}');

  // Bounds for the automatic choice: no smaller than version 4, no larger than version 10.
  final json2 = CkJsonObject();
  json2.updateString('payload.text', 'https://www.chilkatsoft.com/');
  json2.updateInt('encoding.qr.minVersion', 4);
  json2.updateInt('encoding.qr.maxVersion', 10);
  try {
    fmt.qrCode('generate', json2, jsonOut);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print('minVersion 4: version ${jsonOut.intOf('symbols[0].selectedEncoding.version')}');

  // The four symbols, in the order they were made.  The second and the third hold the same data
  // in the same version and differ only in the mask:

  // 

  // Sample output:

  // automatic: version 3, 29 modules wide, mask 2
  // version 8: version 8, 49 modules wide, mask 2
  // version 8, mask 5: version 8, mask 5
  // minVersion 4: version 4
}