问题
I have two models connected by manytomany relationship and I am trying to use formset to create a dynamic form. I am able to save the form but the problem arise when I am trying to edit the saved instance, I don't know how to properly pass the instance to the formset such that it shows the instance data in form for editing
Here are the details:
Models.py
class Player(models.Model):
pname = models.CharField(max_length=50)
hscore = models.IntegerField()
age = models.IntegerField()
def __str__(self):
return self.pname
class Team(models.Model):
tname = models.CharField(max_length=100)
player= models.ManyToManyField(Player)
def __str__(self):
return self.tname
Forms.py
class PlayerForm(forms.ModelForm):
class Meta:
model = Player
fields = '__all__'
PlayerFormset= formset_factory(PlayerForm)
class TeamForm(forms.ModelForm):
player= PlayerFormset()
class Meta:
model = Team
fields = '__all__'
exclude = ["player"]
Views.py
def team(request):
if request.POST:
form = TeamForm(request.POST)
form.player_instances = PlayerFormset(request.POST)
if form.is_valid():
team= Team()
team.tname= form.cleaned_data['tname']
team.save()
if form.player_instances.cleaned_data is not None:
for item in form.player_instances.cleaned_data:
player = Player()
player.pname= item['pname']
player.hscore= item['hscore']
player.age= item['age']
player.save()
team.player.add(player)
team.save()
else:
form = TeamForm()
return render(request, 'packsapp/employee/new.html', {'form':form})
def updateTeam(request,pk):
team = Team.objects.get(id=pk)
form = TeamForm(instance=team)
// something here to initialize the formset ??
if request.method == "POST":
form = TeamForm(request.POST, instance=team)
if form.is_valid():
form.save()
context = {'form': form}
return render(request, 'packsapp/employee/new.html', context)
Html
<html>
<head>
<title>gffdfdf</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<script src="/static/jquery.formset.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
</head>
<body>
<div class="container">
<form id="myForm" action="" method="post" class="">
{% csrf_token %}
<h2> Team</h2>
{% for field in form %}
{{ field.errors }}
{{ field.label_tag }} {{ field }}
{% endfor %}
{{ form.player.management_form }}
<h3> Product Instance(s)</h3>
<table id="table-product" class="table">
<thead>
<tr>
<th>player name</th>
<th>highest score</th>
<th>age</th>
</tr>
</thead>
{% for player in form.player %}
<tbody class="player-instances">
<tr>
<td>{{ player.pname }}</td>
<td>{{ player.hscore }}</td>
<td>{{ player.age }}</td>
<td><input id="input_add" type="button" name="add" value=" Add More "
class="tr_clone_add btn data_input"></td>
</tr>
</tbody>
{% endfor %}
</table>
<button type="submit" class="btn btn-primary">save</button>
</form>
</div>
<script>
var i = 1;
$("#input_add").click(function () {
$("tbody tr:first").clone().find(".data_input").each(function () {
if ($(this).attr('class') == 'tr_clone_add btn data_input') {
$(this).attr({
'id': function (_, id) {
return "remove_button"
},
'name': function (_, name) {
return "name_remove" + i
},
'value': 'Remove'
}).on("click", function () {
var a = $(this).parent();
var b = a.parent();
i = i - 1
$('#id_form-TOTAL_FORMS').val(i);
b.remove();
$('.player-instances tr').each(function (index, value) {
$(this).find('.data_input').each(function () {
$(this).attr({
'id': function (_, id) {
console.log("id", id)
var idData = id;
var splitV = String(idData).split('-');
var fData = splitV[0];
var tData = splitV[2];
return fData + "-" + index + "-" + tData
},
'name': function (_, name) {
console.log("name", name)
var nameData = name;
var splitV = String(nameData).split('-');
var fData = splitV[0];
var tData = splitV[2];
return fData + "-" + index + "-" + tData
}
});
})
})
})
} else {
$(this).attr({
'id': function (_, id) {
console.log("id", id)
var idData = id;
var splitV = String(idData).split('-');
var fData = splitV[0];
var tData = splitV[2];
return fData + "-" + i + "-" + tData
},
'name': function (_, name) {
console.log("name", name)
var nameData = name;
var splitV = String(nameData).split('-');
var fData = splitV[0];
var tData = splitV[2];
return fData + "-" + i + "-" + tData
}
});
}
}).end().appendTo("tbody");
$('#id_form-TOTAL_FORMS').val(1 + i);
$("tbody tr:last :input").each(function () {
$(this).attr({
'id': function (_, id) {
return id.replace(/\d/g, i)
},
'name': function (_, name) {
return name.replace(/\d/g, i)
},
})
})
i++;
});
</script>
</body>
</html>
update:
Use modelformset_factory in the views directly:
def post(request):
tform = TeamForm()
pform = modelformset_factory(Player, form=PlayerForm, extra = 1)
pform = pform(request.POST or None, queryset = Player.objects.filter(id__isnull = True))
if request.method == 'POST':
t = Team()
tform = TeamForm(request.POST, instance=t)
if tform.is_valid() and pform.is_valid():
tform.save()
instances = pform.save(commit=False)
for i in instances:
player = Player()
player.pname = i.pname
player.hscore = i.age
player.age = i.hscore
player.save()
t.player.add(player)
t.save()
return redirect('/exams/dashboard/')
else:
print('invalid data')
return render(request, 'team/team_create.html', {'exform': tform, 'exformset': pform})
def update(request, pk = None):
team = Team.objects.get(id = pk)
tform = TeamForm(instance = team)
pform = modelformset_factory(Player, form=PlayerForm, extra=0)
print("players", Player.objects.filter(team=team))
pform = pform(request.POST or None, queryset=Player.objects.filter(team=team))
if request.method == 'POST':
tform = TeamForm(request.POST, instance=team)
print("tform ", tform)
print("pform ", pform)
if tform.is_valid() and pform.is_valid():
tform.save()
instances = pform.save(commit=False)
for i in instances:
player = Player()
player.pname = i.pname
player.hscore = i.age
player.age = i.hscore
player.save()
t.player.add(player)
t.save()
return redirect('/exams/dashboard/')
else:
print('invalid data')
return render(request, 'team/team_create.html', {'exform': tform, 'exformset': pform})
回答1:
The TeamForm has to set the queryset of the PlayerFormset. The following shows how.
class TeamForm(forms.ModelForm):
player= PlayerFormset()
class Meta:
model = Team
fields = '__all__'
exclude = ["player"]
def __init__(self,*args, **kwargs):
super(TeamForm,self).__init__(*args,**kwargs)
self.player = PlayerFormSet(queryset=Players.objects.filter(team=self.instance)
Information from the documentation: https://docs.djangoproject.com/en/2.2/topics/forms/modelforms/#changing-the-queryset
maybe also worth a look: https://stackoverflow.com/a/34323401/13168118
EDIT:
your PlayerFormset should be created with a modelformset_factory like:
PlayerFormset = modelformset_factory(Player, form=PlayerForm)
modelformset documentation: https://docs.djangoproject.com/en/2.2/ref/forms/models/#modelformset-factory
来源：https://stackoverflow.com/questions/61285171/initialize-a-formset