Adding data to linked table from link on page-CodePudding

Within my Django application, I have two models:

Event and Game

The Event model has a ForeignKey to the Game model.

I have a page that lists all the games using a {% for game in game_list %}, and I'm trying to create a button that will take me to the Events Form to allow me to add an event to the game.

The event form only has 3 fields. project , event_name and event_date. When you land on the event form page I'd like to have the project name populated with the game name from the previous page.

But when I create the link to form my page breaks. Im using:

<a href="{% url 'add-event' game.id %}">Add Key Event</a>

to take to the event form.

Models

class Event(models.Model):

    project = models.ForeignKey(Game, to_field='project_name', on_delete=models.CASCADE)
    event_name = models.CharField(max_length=20)
    event_date = models.DateTimeField(blank=True, null=True)

    def __str__(self):
        return str(self.event_name)

class Game(models.Model):
    project_name = models.CharField(max_length=255, blank=False, unique=True)
    project_website = models.URLField(max_length=255, blank=True)
    project_description = models.TextField(blank=True)
    
    def __str__(self):
        return str(self.project_name)

View

def add_event(request,game_id):
    event = Event.objects.get(pk=game_id)
    form = addEventForm(request.POST or None, instance=event)
    return render(request, 'pages/add_event.html', {'event': event, "form" : form})

URL

path('add_event/<game_id>', view=add_event, name="add-event"),

Error

DoesNotExist at /apps/add_event/13
Event matching query does not exist.
Request Method: GET
Request URL:    http://127.0.0.1:8000/apps/add_event/13
Django Version: 3.2.8
Exception Type: DoesNotExist
Exception Value:    
Event matching query does not exist.

I think the issue is with this line event = Event.objects.get(pk=game_id)

But I'm not sure how what is wrong, other than maybe the view is expecting something else other than the game_id

So I changed the plan and thought I'd just go with a dropdown list that allowed me to select the game to assign the event to. BUT the drop-down is showing the duplicated game.project_names, I think because in the database the project_name has multiple events. How do I get the dropdown to only show once for each project_name?

<select class="form-control" name="choices-single-no-sorting" id="project-tier-entry-level">
    {% for project in event.game.project_name %}
    <option value="" disabled selected hidden>Please Choose...</option>    
    <option>{{ project }}</option>
    {% endfor %}
</select>

CodePudding user response：

I think you should review your view something like this, if its only to create an event:

def add_event(request):
    form = addEventForm(request.POST or None)

    if request.method == 'POST'
        if event_form.is_valid():
            event = event_form.save()

    return render(request, 'pages/add_event.html', {'event': event, "form" : form})

You can improve it to manage also event's updates:

def manage_event(request, event_id=0):
    if event_id == 0:
        # Create a new event: there is no instance yet of the event
        form = addEventForm(request.POST or None)
    else:
        # Update an existing event, you can instantiate it
        form = addEventForm(request.POST or None, instance=event)

    if request.method == 'POST'
        # You are posting either a creation or an update
        if event_form.is_valid():
        # If you need to add control before saving, you need to distinguish both like for the form creation
            event = event_form.save()

    return render(request, 'pages/add_event.html', {'event': event, "form" : form})

CodePudding user response：

Maybe the game_id is actually a string, so try converting it to an integer first. In other words, change it to

event = Event.objects.get(pk=int(game_id))

path('add_event/<int:game_id>', view=add_event, name="add-event")

or both.

Try changing

<select class="form-control" name="choices-single-no-sorting" id="project-tier-entry-level">
    {% for project in event.game.project_name %}
    <option value="" disabled selected hidden>Please Choose...</option>    
    <option>{{ project }}</option>
{% endfor %}

to:

<select class="form-control" name="choices-single-no-sorting" id="project-tier-entry-level">
    <option value="" disabled selected hidden>Please Choose...</option>
    {% for project in event.game.project_name %}
    <option>{{ project }}</option>
    {% endfor %}
</select>

The 'Please choose' option should not be in the loop.