callbackButton method

KeyboardBuilder callbackButton({
  1. required String label,
  2. _Button payload = const {},
  3. Color color = Color.SECONDARY,
})

Allows without sending a message from the user to receive a notification of a button click and perform the necessary action

builder.callbackButton(
 label: 'Buy a coffee',
 payload: {
  "command": "buy",
  "item": "coffee"
 }
);

Implementation

KeyboardBuilder callbackButton(
    {required String label,
    _Button payload = const {},
    Color color = Color.SECONDARY}) {
  if (label.length > 40) {
    throw RangeError('Maximum length of label 40 characters');
  }

  return _addButton({
    'color': _colors[color.index],
    'action': {
      'label': label,
      'payload': _serializePayload(payload),
      'type': 'callback'
    }
  });
}