Done!!!

class Task extends StatefulWidget {
  final String nome;
  final String foto;
  final int dificuldade;

  const Task(this.nome, this.foto, this.dificuldade, {Key? key})
      : super(key: key);

  @override
  State<Task> createState() => _TaskState();
}

class _TaskState extends State<Task> {
  int nivel = 0;
  List<Color> currentColor = [Colors.blue, Colors.green,Colors.amber,Colors.orange,Colors.red,Colors.black];
  int colorIndex = 1;

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.all(8.0),
      child: Stack(
        children: [
          Container(
            decoration: BoxDecoration(
                borderRadius: BorderRadius.circular(4),
                color: currentColor[colorIndex]),
            height: 140,
          ),
          Column(
            children: [
              Container(
                decoration: BoxDecoration(
                  borderRadius: BorderRadius.circular(4),
                  color: Colors.white,
                ),
                height: 100,
                child: Row(
                  mainAxisAlignment: MainAxisAlignment.spaceBetween,
                  children: [
                    Container(
                      decoration: BoxDecoration(
                        borderRadius: BorderRadius.circular(4),
                        color: Colors.black26,
                      ),
                      height: 100,
                      width: 72,
                      child: ClipRRect(
                        borderRadius: BorderRadius.circular(4),
                        child: Image.asset(
                          widget.foto,
                          fit: BoxFit.cover,
                        ),
                      ),
                    ),
                    Column(
                      mainAxisAlignment: MainAxisAlignment.center,
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: [
                        SizedBox(
                          width: 200,
                          child: Text(
                            widget.nome,
                            style: const TextStyle(fontSize: 24),
                            overflow: TextOverflow.ellipsis,
                          ),
                        ),
                        Difficulty(difficultyLevel: widget.dificuldade,)
                      ],
                    ),
                    SizedBox(
                      height: 52,
                      width: 52,
                      child: ElevatedButton(
                          onPressed: () {
                            setState(() {
                             if(colorIndex != 5 &&  (nivel/widget.dificuldade) == 10){
                                colorIndex++;
                                nivel = 0;
                              } else if(colorIndex != 5 &&  nivel/widget.dificuldade != 10){
                                nivel++;
                              } else {
                                nivel++;
                              }

                              // print('colors.lengh: ${currentColor.length}');
                            });
                          },
                          child: Column(
                            mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                            crossAxisAlignment: CrossAxisAlignment.end,
                            children: const [
                              Icon(Icons.arrow_drop_up),
                              Text('UP', style: TextStyle(fontSize: 12))
                            ],
                          )),
                    ),
                  ],
                ),
              ),
              Row(
                mainAxisAlignment: MainAxisAlignment.spaceBetween,
                children: [
                  Padding(
                    padding: const EdgeInsets.all(8.0),
                    child: SizedBox(
                        width: 200,
                        child: LinearProgressIndicator(
                          color: Colors.white,
                          value: widget.dificuldade > 0
                              ? (nivel / widget.dificuldade) / 10
                              : 1,
                        )),
                  ),
                  Padding(
                    padding: const EdgeInsets.all(12),
                    child: Text(
                      'Nivel: $nivel',
                      style:
                      const TextStyle(color: Colors.white, fontSize: 16),
                    ),
                  ),
                ],
              ),
            ],
          )
        ],
      ),
    );
  }
}