CheckboxListTile(
                activeColor: Colors.red,
                checkColor: Colors.yellow,
                value: _newValue2,
                onChanged: (newValue) {
                  setState(() {
                    _newValue2 = newValue;
                    timeDilation = 13;
                  });
                },
                title: Text('title'),
                subtitle: Text('subtitle'),
                isThreeLine: false,
                dense: true,
                secondary: Icon(Icons.hourglass_empty),
                selected: true,
                controlAffinity: ListTileControlAffinity.leading, //决定选择框的位置
              ),