You could always try writing a custom template tag or filter as someone
else suggested earlier in the thread before resorting to JavaScript.
Cheers,
AT
On Mar 21, 2012 5:41 PM, "Larry Martell" <larry.mart...@gmail.com> wrote:
> On Wed, Mar 21, 2012 at 12:52 PM, James <eire1...@gmail.com> wrote:
> >
> >
> > On Wednesday, March 21, 2012 10:41:08 AM UTC-4, Larry....@gmail.comwrote:
> >>
> >> On Wed, Mar 21, 2012 at 7:53 AM, James <> wrote:
> >> >
> >> >
> >> > On Wednesday, March 21, 2012 8:47:23 AM UTC-4, larry....@gmail.com
> >> > wrote:
> >> >>
> >> >> This is probably a stupid newbie question ....
> >> >>
> >> >> I want to access a column of data in a row using forloop.counter, but
> >> >> I cannot get it to work.
> >> >>
> >> >> In my test code, if I display {{ forloop.counter }} I get 2
> >> >> If I display {{ headers.0.2 }} I get ToolType
> >> >> But if I display {{ headers.0.forloop.counter }} I get nothing
> >> >>
> >> >> What is the proper syntax for this?
> >> >
> >> >
> >> > the forloop.counter and friends will simply give you information about
> >> > the
> >> > iteration, it won't give you any information about the data in the
> >> > queryset
> >>
> >> Yes, I realize that. I am using it withing a loop to try an access a
> >> specific item of data. The code I showed was just an example from one
> >> iteration of the loop.
> >>
> >> > (I'm assuming this is what you mean when you say column).
> >> >
> >> > Here are the
> >> >
> >> > docs
> https://docs.djangoproject.com/en/dev/ref/templates/builtins/?from=olddocs#for
> >> >
> >> > If you want to access the column of data, assuming it's referenced
> from
> >> > a
> >> > model, just the attribute of that model. If you passed in a list to
> the
> >> > template, you just use the django "dot" look-up syntax.
> >>
> >> Perhaps my question wasn't clear. I have a list called headers. From
> >> within a for loop I want the n'th item from the first row. In the loop
> >> I am trying to access {{ headers.0.forloop.counter }} but I get no
> >> value from that. But if I hard code the number (as a test), e.g.: {{
> >> headers.0.2 }} then I do get the value.
> >
> > With regards to your reply:
> >
> >
> >> Yes, I realize that. I am using it withing a loop to try an access a
> >> specific item of data. The code I showed was just an example from one
> >> iteration of the loop.
> >
> >
> > You can't use forloop and friends in the manner you attempting to use it.
> > It's The reason is, headers.0 has no attribute named "forloop"
> >
> > The best that you could do here, in this situation, is to create a custom
> > filter and pass it forloop.counter as variable like so:
> > {{ headers.0|forloop.counter }} You will of course have to write that
> filter
> > out first, register it, and install it in the template.
> >
> > I'm still not sure if this is the right approach. Why not just iterate
> over
> > the list itself, if you want to print the nth item within the list?
>
> That would be really inefficient, as the table can have thousands of
> rows, with 30 columns each. I'd have to iterate through the header row
> for each column in each row to get the value to put into the href.
>
> > Or,
> > structure the list/queryset from the view such that you don't have to do
> > such acrobatics.
> >
> >> But if I hard code the number (as a test), e.g.: {{
> >> headers.0.2 }} then I do get the value.
> >
> >
> > This works because headers.0 has an attribute that works by way of the
> > django dot look up. See Tom Evan's post regarding this.
> >
> > It seems to me that you have a list of lists (and not a single list). In
> > which case, you can just iterate over the first list and iterate over the
> > second list. If you need some control flow, just use the standard if /
> else
> > conditions. But, maybe I'm missing something?
>
> Yes, I think you are. I have 2 header rows, and thousands of data
> rows. For each column in each data row I have to construct a href. One
> of the parameters in the href comes from the first header row. The
> header rows get processed first, then the data rows (to build the
> table). So by the time I am processing the data I don't have the
> header any more. I should probably just do this in javascript.
>
> > Even easier would be to use django's introspect feature and create models
> > based on the tables in the DB, query the DB using the models and create
> > querysets. Then you can access and display the data in a more
> > coherent manner.
> >
> > see the docs here for
> > introspection:
> https://docs.djangoproject.com/en/dev/howto/legacy-databases/?from=olddocs
>
>
> That already is the case. I am trying to add functionality to an existing
> app.
>
> --
> You received this message because you are subscribed to the Google Groups
> "Django users" group.
> To post to this group, send email to django-users@googlegroups.com.
> To unsubscribe from this group, send email to
> django-users+unsubscr...@googlegroups.com.
> For more options, visit this group at
> http://groups.google.com/group/django-users?hl=en.
>
>
--
You received this message because you are subscribed to the Google Groups
"Django users" group.
To post to this group, send email to django-users@googlegroups.com.
To unsubscribe from this group, send email to
django-users+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/django-users?hl=en.
