Using Form Input Widgets

<Checkbox
  value: true,
  onChanged: (bool? newValue) {
    setState(() {
      value = newValue!;
    });
  },
/>

<Checkbox
  value: false,
  onChanged: (bool? newValue) {
    setState(() {
      value = newValue!;
    });
  },
  activeColor: Colors.blue,
  checkColor: Colors.white,
/>

CheckboxListTile(
  title: Text('Enable notifications'),
  value: true,
  onChanged: (bool? newValue) {
    setState(() {
      // Update the checkbox state
    });
  },
)

CheckboxListTile(
  title: Text('Select all'),
  value: null,
  tristate: true,
  onChanged: (bool? newValue) {
    setState(() {
      // Handle tristate logic
    });
  },
)

class RadioExample extends StatefulWidget {
  @override
  _RadioExampleState createState() => _RadioExampleState();
}

class _RadioExampleState extends State<RadioExample> {
  String? selectedValue = 'option1';

  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        RadioListTile<String>(
          title: Text('Option 1'),
          value: 'option1',
          groupValue: selectedValue,
          onChanged: (value) {
            setState(() {
              selectedValue = value;
            });
          },
        ),
        RadioListTile<String>(
          title: Text('Option 2'),
          value: 'option2',
          groupValue: selectedValue,
          onChanged: (value) {
            setState(() {
              selectedValue = value;
            });
          },
        ),
      ],
    );
  }
}

class RadioFormExample extends StatefulWidget {
  @override
  _RadioFormExampleState createState() => _RadioFormExampleState();
}

class _RadioFormExampleState extends State<RadioFormExample> {
  String? _selectedOption;

  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        RadioListTile<String>(
          title: Text('Option 1'),
          value: 'option1',
          groupValue: _selectedOption,
          onChanged: (value) {
            setState(() {
              _selectedOption = value;
            });
          },
        ),
        RadioListTile<String>(
          title: Text('Option 2'),
          value: 'option2',
          groupValue: _selectedOption,
          onChanged: (value) {
            setState(() {
              _selectedOption = value;
            });
          },
        ),
      ],
    );
  }
}

RadioListTile<String>(
  title: Text('Email'),
  subtitle: Text('Receive notifications via email'),
  value: 'email',
  groupValue: _selectedOption,
  onChanged: (value) {
    setState(() {
      _selectedOption = value;
    });
  },
)

Switch(
  value: isSwitched,
  onChanged: (bool newValue) {
    setState(() {
      isSwitched = newValue;
    });
  },
)

Switch(
  value: isSwitched,
  onChanged: (bool newValue) {
    setState(() {
      isSwitched = newValue;
    });
  },
  activeColor: Colors.blue,
  inactiveThumbColor: Colors.grey,
  inactiveTrackColor: Colors.lightBlue,
)

SwitchListTile(
  title: Text('Enable notifications'),
  subtitle: Text('Receive push notifications'),
  value: notificationsEnabled,
  onChanged: (bool newValue) {
    setState(() {
      notificationsEnabled = newValue;
    });
  },
)

SwitchListTile(
  title: Text('Dark Mode'),
  value: isDarkMode,
  onChanged: (bool newValue) {
    setState(() {
      isDarkMode = newValue;
    });
  },
  activeColor: Colors.blue,
  inactiveColor: Colors.grey,
)

Slider(
  value: _currentValue,
  min: 0.0,
  max: 100.0,
  divisions: 100,
  onChanged: (double value) {
    setState(() {
      _currentValue = value;
    });
  },
)

Slider(
  value: _currentValue,
  min: 0.0,
  max: 100.0,
  activeColor: Colors.blue,
  inactiveColor: Colors.grey,
  thumbColor: Colors.red,
  onChanged: (double value) {
    setState(() {
      _currentValue = value;
    });
  },
)

<RangeSlider
  values: const RangeValues(20.0, 80.0),
  min: 0.0,
  max: 100.0,
  divisions: 100,
  onChanged: (RangeValues values) {
    setState(() {
      _rangeValues = values;
    });
  },
/>

<RangeSlider
  values: _rangeValues,
  min: 0.0,
  max: 100.0,
  divisions: 100,
  labels: RangeLabels(_rangeValues.start.toStringAsFixed(1), _rangeValues.end.toStringAsFixed(1)),
  onChanged: (RangeValues values) {
    setState(() {
      _rangeValues = values;
    });
  },
/>

class MyDropdownExample extends StatefulWidget {
  @override
  _MyDropdownExampleState createState() => _MyDropdownExampleState();
}

class _MyDropdownExampleState extends State<MyDropdownExample> {
  String? _selectedValue;

  @override
  Widget build(BuildContext context) {
    return DropdownButton<String>(
      value: _selectedValue,
      hint: Text("Select an option"),
      items: <String>["Option 1", "Option 2", "Option 3"]
          .map<DropdownMenuItem<String>>((String value) {
        return DropdownMenuItem<String>(
          value: value,
          child: Text(value),
        );
      }).toList(),
      onChanged: (String? newValue) {
        setState(() {
          _selectedValue = newValue;
        });
      },
    );
  }
}

DropdownButton<String>(
  value: _selectedValue,
  hint: Text("Choose a color", style: TextStyle(color: Colors.grey)),
  items: <String>["Red", "Green", "Blue"]
      .map<DropdownMenuItem<String>>((String value) {
    return DropdownMenuItem<String>(
      value: value,
      child: Text(value, style: TextStyle(color: Colors.black)),
    );
  }).toList(),
  onChanged: (String? newValue) {
    setState(() {
      _selectedValue = newValue;
    });
  },
  style: TextStyle(fontSize: 16, color: Colors.blue),
  iconSize: 30,
  elevation: 5,
)

DropdownButtonFormField<String>(
  decoration: InputDecoration(
    labelText: 'Select Country',
    border: OutlineInputBorder(),
  ),
  value: 'US',
  items: <String>['US', 'CA', 'UK'].map((String item) {
    return DropdownMenuItem<String>(
      value: item,
      child: Text(item),
    );
  }).toList(),
  onChanged: (String? newValue) {
    setState(() {
      selectedCountry = newValue!;
    });
  },
)

final _formKey = GlobalKey<FormState>();
String? selectedCountry;

DropdownButtonFormField<String>(
  decoration: InputDecoration(
    labelText: 'Country',
    border: OutlineInputBorder(),
  ),
  value: selectedCountry,
  items: <String>['US', 'CA', 'UK'].map((String item) {
    return DropdownMenuItem<String>(
      value: item,
      child: Text(item),
    );
  }).toList(),
  validator: (String? value) {
    if (value == null || value.isEmpty) {
      return 'Please select a country';
    }
    return null;
  },
  onChanged: (String? newValue) {
    setState(() {
      selectedCountry = newValue!;
    });
  },
)

DropdownMenu<String>(
  items: [
    DropdownMenuItem(value: 'option1', child: Text('Option 1')),
    DropdownMenuItem(value: 'option2', child: Text('Option 2')),
  ],
  value: 'option1',
  onChanged: (value) {
    // Handle selection
  },
)

DropdownMenu<String>(
  items: [
    DropdownMenuItem(value: 'apple', child: Text('Apple')),
    DropdownMenuItem(value: 'banana', child: Text('Banana')),
  ],
  value: null,
  hint: Text('Select a fruit'),
  onChanged: (value) {
    if (value != null) {
      print('Selected: $value');
    }
  },
)

class CountryAutocomplete extends StatelessWidget {
  final List<String> countries = [
    'United States',
    'Canada',
    'Mexico',
    'Brazil',
    'Argentina'
  ];

  @override
  Widget build(BuildContext context) {
    return Autocomplete<String>(
      optionsBuilder: (TextEditingValue value) {
        if (value.text.isEmpty) {
          return const Iterable<String>.empty();
        }
        return countries.where((country) =>
            country.toLowerCase().contains(value.text.toLowerCase()));
      },
      onSelected: (String selection) {
        print('Selected: $selection');
      },
      displayStringForOption: (String option) => option,
    );
  }
}