Question

python 2.6, with Django 1.3.1 on Redhat 6.3

In Django how would I go about changing the background colour of a table cell depending on it’s value, as in if it is over 10 it’s red, between 7 and 9 it’s orange, below 7 is green etc..

The data is coming from a non django database/model.

I am using a standard template to iterate over the table, but would have no problem using a custom template for this.

I see the following

Link

that deals with changing cell colour but it seems to be based on a concrete value in the cell as opposed to being within a range.

using the following test code for a view

def dashboard(request):
  if request.user.is_authenticated():
      user = request.user.first_name
  else:
      return redirect('/bcpm/login')


  table_headers = ['Colmun1','Column2','Column3']
  table_data = [['test1',2,3],['test2',2,4],['test3',5,5]]
  page_title = 'Dashboard'

  template_dict = {'header_list':table_headers, 'page_title':page_title,
                         'results':table_data,'username':user}
  return render_to_response('dashboard.html',template_dict)enter code here

and the following generic table template:

<table border=1 width=98% style="margin-left:12px;">
        <tr>
            {% for item in header_list %}
            <th>{{ item }}</th>
            {% endfor %}
        </tr>


            {% for row in results %}
            <tr>
                {% for line in row %}
                <td>{{line}}</td>
                {% endfor %}
            </tr>
            {% endfor %}

    </table>

Thanks.

---

Almost solved;

With the help of brianbuck below i came up with the following,
in the view:

def dashboard(request):
    if request.user.is_authenticated():
        user = request.user.first_name
    else:
       return redirect('/login'

    table_headers = ['Column1','Column2','Column3']
    table_data = [['name','thing',8],['name','thing',5]]
    page_title = 'Dashboard'

    template_dict = {'header_list':table_headers, 'page_title':page_title,
                         'results':table_data,'username':user}
    return render_to_response('dashboard.html',template_dict)

in the template;

<table border=1 width=68% style="margin-left:12px;">
        <tr>
            {% for item in header_list %}
            <th>{{ item }}</th>
            {% endfor %}
        </tr>


            {% for element in results %}
          <tr>
            <td> {{ element.0 }} </td>
            <td> {{ element.1 }} </td>
            {% if element.3 > 7 %} <td class="red"> {{ element.3 }} </td> 
            {% else %} <td class="green"> {{ element.3 }} </td> {% endif %}
          </tr>
            {% endfor %}

    </table>
{% endif %}

I really could not get it to do an {% if or %}
When I tried to set it up to do a

“greater than or equal to 7 or less than or equal to 8”

it would always evaluate to this expression for a number higher than 7, even though the first if statement should be true for anything higher than 9.

I am using Django 1.3 and I think there may be some limitations of the if/else and the multiple evaluations, either way I have it 80% working with two values red/green and that is good enough for the moment.

Thank you all.

---

Got it to work like this;

{% for element in results %}
            <tr>
            <td> {{ element.0 }} </td>
            <td> {{ element.1 }} </td>
            <td> {{ element.2 }} </td>
            <td> {{ element.3 }} </td>
            {% if element.4 > 8 %} <td class="red"> {{ element.4 }} </td>
            {% else %}{% if element.4 > 8 or element.4 >= 5 %} <td class="orange"> {{ element.4 }} </td>
            {%else %}{% if element.4 < 5 %}<td class="green"> {{ element.4 }} </td>
            {% endif %}{% endif %}{% endif %}

            <td> {{ element.5 }} </td>

This would not be required if you have a version of Django that supports elif or if you add some of the django snippets that are available to extend your django installation.

Hurrah.

Answer 1

This assumes you have three classes named:

td.red {
    backgroundColor: red;
}
td.orange {
    backgroundColor: orange;
}
td.green {
    backgroundColor: green;
}

…

Django 1.3 doesn’t have elif so you will probably have to do it a bit more clunky.

<td class="
    {% if val >= 10 %}red{% endif %}
    {% if val >= 7 or val <= 9 %}orange{% endif %}
    {% if val < 7 %}green{% endif %}">
    {{ val }}
</td>