Using a Model Form

Using a ModelForm, at least to display a blank form, 0:00 is exactly the same work as using a regular form. 0:03 You instantiate it and send it to the template. 0:06 You even render it to HTML in the same way. 0:09 Where they definitely deviate, though, is in the processing of them. 0:12 You still use the normal isValid method, but after that, 0:16 you can save instances to the database. 0:18 This sounds like something we should take to workspaces. 0:20 All right, so I want to make a couple of views for 0:24 dealing with creating quizzes and editing quizzes. 0:28 And I know that I want these to be something that only logged 0:32 in users can do, so we need to import a little thingy here. 0:37 And so what we wanna do is. 0:41 We probably wanna give back some messages at some point. 0:47 I'm gonna import this just in case. 0:50 Maybe we use it, maybe we don't, but for right now I'm gonna import it. 0:51 And then django.contrib.auth.decorators 0:55 import login_required, which this decorator 1:00 lets us mark a view as requiring a logged in user. 1:06 If you've done the flask courses, we've done something like this. 1:12 Basically it just makes it so, you log into the admin, and 1:17 then you can go see our quiz creation, quiz editing thing. 1:20 You can't do it unless you are doing that. 1:25 And then from django.http import HttpResponseRedirect. 1:30 You know we're gonna need that, because we gotta be able to send people back and 1:35 forth to places. 1:39 And then, we're gonna need forms, so from.import forms. 1:40 All right, let's get started with our views, and I'm gonna bump 1:46 this up a little bit just so that I know this is above the closed captioning. 1:51 All right, cool. 1:57 So first let's make a view for creating a quiz. 1:58 So first of all we'll mark it as login_required and 2:04 then let's call this quiz_create, pretty explanatory title there. 2:08 It's gonna take the request and we wanna get the course_pk. 2:13 We wanna know what course this quiz belongs to. 2:16 And so of course first we wanna get the course that it belongs to. 2:20 So we'll do a get_object_or_440, you should remember this from Django basics, 2:25 models.Course and the pk of that should be the course_pk. 2:32 And then just like with our suggestion view, 2:37 we wanna make a form that's just blank, so forms.QuizForm. 2:41 So there's just nothing in there, so cool, simple enough, right? 2:46 So if request.method is equal to POST, 2:51 so somebody has posted our form, then we wanna do a new version of the form. 2:56 And we wanna say request.POST. 3:05 I gotta spell it and capitalize it correctly. 3:09 And now if that new form is valid, then we're gonna do, 3:12 this is a little bit different. 3:17 We're gonna make a new variable, called quiz, and we're gonna say form.save. 3:21 So normally, if we were to just close this right there, it just saves a new 3:25 instance of the quiz in the database, but we're missing something. 3:30 We don't have the quiz associated with the course. 3:34 So, we need to do that. 3:38 So what we're gonna do is we're gonna do form.save and we're say commit=False. 3:40 I kinda wish this was named a little differently but 3:45 I don't know what I would name it. 3:48 But commit normally is true, commit=False means 3:49 don't actually put this in the database, just make the model instance for me. 3:53 So make the model, hold to it in memory, don't actually do anything with it. 3:58 Let me modify some stuff and then we'll save it directly in a moment. 4:03 So now we have quiz which is just a quiz instance. 4:07 So let's do quiz.course is equal to the course that we 4:10 got up at the top there and then let's do quiz.save. 4:14 And you know what for, let's just do messages.add_message, 4:19 request, message.SUCCESS. 4:26 And we'll just say, Quiz added! 4:30 I'm a big fan of exclamation marks if you hadn't noticed. 4:36 And then we'll return HttpResponseRedirect and 4:40 we just wanna go back to the quiz, get_absolute_url. 4:44 We don't need reverse at this point. 4:49 All right, and so, out here, 4:53 if it's not a post, you can do else, if you want, but you don't have to. 4:55 Out here, we're just gonna do return render (request, 5:00 'courses/quiz_form.html', and 5:07 {'form': form}). 5:12 All right, so let's go make our template and our URL, 5:15 just to make sure we got everything done correctly. 5:20 Let's go do URLs first. 5:24 So if we come over here to our URLs, and 5:27 we wanna put in an edit quiz one, or create quiz one, sorry. 5:30 So, URL and let's see, 5:35 r and then ?P, there we go, 5:39 course_pk would be \d+ just like we had before, 5:44 and then we'll say create_quiz and 5:50 this will go to views.quiz_create, and we'll give it a name of create_quiz. 5:54 Easy enough. 6:01 All right, and then for templates inside courses here, 6:03 we said we were gonna call it quiz_form. 6:07 Ideally, we'll get to use the same template for 6:10 both creating a quiz and editing a quiz. 6:14 So let's see what that should look like. 6:18 So this should be extends course/layout.html. 6:21 And then we should have block content, 6:31 div class="row". 6:36 And then inside of there, we wanna do this. 6:40 And let's just say, Make a new quiz, and 6:43 then form method="POST" and action= nothing. 6:48 And then inside there let's do our 6:54 csrf_token and then our form.as_p, 6:59 and then our input type="submit" 7:04 class="button" value="Save". 7:09 All right, cool. 7:14 And then we need to end our block. 7:16 And I think there's actually something, if we come look at text_detail, yeah, 7:20 we've got a couple of extra things here, let's bring those in. 7:28 This is stuff that's just inside the templates, 7:34 I'll let you look through all this if you want. 7:36 Let's send that quiz back out. 7:40 [SOUND] Or, sorry, not the quiz, the course. 7:43 All right, there we go. 7:49 So then here, we can say 7:50 New Quiz cuz for now it is. 7:55 And we can say course.title and block.super. 8:02 And that right there, that will let us have a link back to the course. 8:07 And it looked like this was supposed to be columns. 8:16 And, if I remember correctly, we need to do block.super right here. 8:20 All of this is just design details, 8:25 you don't have to worry about doing all of this stuff. 8:27 So let's add here, on this course detail, let's add a link for adding a new quiz. 8:29 So if we come over here and we look at our course detail, 8:37 down here at the bottom, let's do if user.is_authenticated 8:42 which just checks to make sure that someone is logged in. 8:48 And then we'll end our if. 8:53 Let's do an hr and then a href= url 'courses:create_quiz', 8:57 course_pk would equal step., 9:06 actually I think we have, yeah, 9:10 we have course, course.pk, course.id. 9:15 And then let's say class="button". 9:20 And let's just say New Quiz. 9:25 All right, so if we refresh this, cool, 9:30 there's our new quiz button, let's click new quiz yep. 9:33 Courses. 9:42 Cool, bam, make a new quiz, and there's our thing. 9:45 Awesome, we should be able to send this through and make a new quiz, so 9:49 let's make a new quiz, and we'll just say Review: Strings. 9:54 Let's talk about strings. 9:59 And it's gonna have five questions, and the order is gonna be three. 10:03 Hit Save, and we get to see the Review: Strings. 10:10 We get Quiz added. 10:14 And if we look at Python Basics, now we have Review: Strings right here, and 10:15 we can click on Review: Strings. 10:19