Changes between Version 7 and Version 8 of CookBookManipulatorCustomManipulator

Timestamp:

Jun 13, 2006, 3:48:27 PM (18 years ago)

Author:

brantley

Comment:

Updated it for post-magic-removal.

CookBookManipulatorCustomManipulator

@@ -1 @@
-Using Manipulators can be annoying and confusing, use this to create simple, elegant ones:
+Using Manipulators can be rather cumbersome.  Here is a class to simplify the process.
 
 {{{
 #!python
-from django.core import formfields, validators
+from django import forms
+from django.core import validators
 
-class Manipulator(formfields.Manipulator):
+class Manipulator(forms.Manipulator):
     default = {}
     done = False
     
-    def getData(self, request):
+    def __bool__(self):
+        return self.done
+    
+    def get_data(self, request):
         return request.POST
     
-    def getForm(self, data, errors):
-        return formfields.FormWrapper(self, data, errors)
+    def get_form(self, data, errors):
+        return forms.FormWrapper(self, data, errors)
     
     def process(self, request):
-        data = self.getData(request)
+        data = self.get_data(request)
         if data:
             new_data = data.copy()
@@ -28 +32 @@
             errors = {}
             new_data = self.default
-        self.form = self.getForm(new_data, errors)
+        self.form = self.get_form(new_data, errors)
         return self.form
 
     def complete(self, request, data):
-        pass
+        self.save()
 }}}
 
-Now to use, subclass it, and fill in the necessary methods ("{{{__init__}}}" and "{{{complete}}}"), also give it the fields:
+Now to use: you should subclass it and fill in the necessary methods ("{{{__init__}}}" and "{{{complete}}}"), and provide fields:
 
 {{{
 #!python
 class PollEdit(Manipulator):
+    # Provide the fields.
     fields = (
-        formfields.TextField("title", maxlength=32, is_required=True),
-        formfields.TextField("question", maxlength=128, is_required=True),
+        forms.TextField("title", maxlength=32, is_required=True),
+        forms.TextField("question", maxlength=128, is_required=True),
     )
-        
+
     def __init__(self, poll):
-        # You can also define your fields here, if you'd like.
+        # We could also provide our fields here, which is usefull if you have
+        # custom validators that you need to reference off of "self."
+
+        # Save a reference to our poll.
         self.poll = poll
-        ## Luca M.: 03/09/2006 
-        ## I've to uncomment the following line to fill the form with the current data
-        # self.default = poll.__dict__
-        ## Is this correct ? I'm using django 0.91
+
+        # Set our default dictionary to match our poll object.
+        # That way the data populating the fields will match our current poll.
+        self.default = poll.__dict__
         
     def complete(self, request, data):
+        # This is executed after the user submits valid data.
+
+        # Set the poll's title to the user-submited 'title' in our data.
         self.poll.title = data['title']
+
+        # Same with 'question'
         self.poll.question = data['question']
+
+        # Don't forget to save.
         self.poll.save()
 
@@ -65 +80 @@
 #!python
 def edit_poll(request, id):
-    poll = polls.get_object(pk=id)      #Assume it works
-    manipulator = PollEdit(poll)
-    form = manipulator.process(request)    #Process returns a form if it's needed
-    if (form):
-         return render_to_response('polls/edit_form', {'form': form})
-    else:
+    poll = get_object_or_404(Poll, pk=id)  # Get our poll object.
+    manipulator = PollEdit(poll)    # Create the manipulator.
+    manipulator.process(request)    # Process the request.
+    if (manipulator.done):          # If we are done, redirect to the poll view page.
          return HttpResponseRedirect("/polls/%d" % poll.id)
+    else:                           # Otherwise, we render the form.
+         return render_to_response('polls/edit_form', {'form': manipulator.form})
 }}}
 
-Here's a custom Add Manipulator I like to build off of first, so that the fields are the same:
+Here's a custom Add Manipulator.  Here we can sub-class the first manipulator, so that the fields are the same:
 
 {{{
@@ -80 +95 @@
 class PollAdd(PollEdit):        
     def __init__(self):
+        # Set our default values.
         self.default = {'title': "Unnamed", 'question': 'Insert your question here.'}
-        #This sets your default values.
     
     def complete(self, request, data):
+        # Create a new poll with our data.
         poll = polls.Poll(title=data['title'], question=data['question'])
         poll.save()
+        # It'd be nice to be able to get the poll back.
         return poll
 
@@ -95 +112 @@
 #!python
 def add_poll(request):
-    manipulator = PollAdd()
-    result = manipulator.process(request)
-    if (manipulator.done): #Are we done processing?
-         return HttpResponseRedirect("/polls/%d" % result.id)
-    else: #Otherwise, place the form.
+    manipulator = PollAdd()             # Create the manipulator
+    poll = manipulator.process(request) # Process the request
+    if (manipulator.done):              # Are we done processing?
+         return HttpResponseRedirect("/polls/%d" % poll.id)
+    else:                               # Otherwise, respond with the form.
          return render_to_response('polls/new_form', {'form': manipulator.form})
 }}}