如果这个 django 表单本身也生成选项，为什么它不接受我的输入？

Question

It is a competition manager that matches the participants of a competition randomly, I call these pairs games. The game is a django model with an attribute called "ganador" to store the winner of the game. To choose the winner I use a modelform_factory called formaGanador and exclude all the attributes of the model except the "ganador" attribute. The attribute "ganador" has an option of "choices" so that the form only allows to choose one of the participants of that game and not participants of other games. Finally, when I select a participant from the list and press the submit button on the form, I receive the following response: Select a valid choice. Player A is not one of the available choices.

model for games in model.py:

class Juego(models.Model):
    torneo = models.ForeignKey(Torneo, on_delete=models.CASCADE, null=False)
    ronda = models.ForeignKey(Ronda, on_delete=models.CASCADE, null=False)
    jugadorA = models.ForeignKey(Jugador, on_delete=models.SET_NULL, null=True, related_name='jugadorA')
    jugadorB = models.ForeignKey(Jugador, on_delete=models.SET_NULL, null=True, related_name='jugadorB')
    puntuacionA = models.IntegerField(default=0)
    puntuacionB = models.IntegerField(default=0)
    ganador = models.ForeignKey(Jugador, on_delete=models.SET_NULL, null=True, default=None, choices=[('Jugador A', 'Jugador A'), ('Jugador B', 'Jugador B')])

creating the form in the views:

GanadorForm = modelform_factory(Juego, exclude=['torneo', 'ronda', 'jugadorA', 'jugadorB', 'puntuacionA', 'puntuacionB'])

passing and receiving the form "formaganador" from the template:

def detalleTorneo(request, id):
    torneo = Torneo.objects.get(pk=id)
    jugadoresPares = False
    jugadores = torneo.jugadores.all()
    no_jugadores = jugadores.count()
    rondas = Ronda.objects.filter(torneo=torneo)
    juegos = Juego.objects.filter(torneo=torneo)

    if request.method == 'POST':
        formaGanador = GanadorForm(request.POST)
        if formaGanador.is_valid():
            formaGanador.save()
    else:
        formaGanador = GanadorForm()

    if (no_jugadores % 2) == 0:
        jugadoresPares = True

    return render(request, 'torneos/detalle.html', {'juegos': juegos, 'torneo': torneo, 'no_jugadores': no_jugadores, 'jugadoresPares': jugadoresPares, 'rondas': rondas, 'formaGanador': formaGanador})

displaying the form "formaGanador" in the template:

    {% for ronda in rondas %}
        <h3>Ronda {{ronda.numero}}</h3>
        <ul>
            {% for juego in juegos %}
                {% if juego.ronda == ronda %}
            <li><form method="post"><strong>{{juego.jugadorA.nombre}} {{juego.jugadorA.apellido}} vs {{juego.jugadorB.nombre}} {{juego.jugadorB.apellido}}</strong> | {{formaGanador}} <button type="submit">Ingresar Resultados</button>{% csrf_token %}<br></form></li>
                {% endif %}
            {% endfor %}
        </ul>
    {% endfor %}

apologies for the variables in Spanish.

Answer 1

Django doesn't generate the options itself. You do by setting the choices option in the genador field definition. The options you're specifying are invalid, because genador is a foreign key field and, therefore, needs a reference to a Jugador instance. “Jugador A” is just a string not a Jugador instance.

Instead of restricting the choices in your model, you can implement a modelchoicefield in your form with a query set as needed ( docs ).