How to reset cycle counter? - django

Question

I have in template this:
{% for item in items %}
{% ifchanged item.st2 %}
<div class="clear"></div>
<div class="item-title">{{ item.get_st2 }}</div>
{% endifchanged %}
<div class="cell {% cycle 'clear tco1' 'tco' 'tco' 'tco2' 'clear tce1' 'tce' 'tce' 'tce2' %}">{{ item.name }}</div>
{% endfor %}
and it shows things like this:
------------------ st2 name 1 -------------------
+-----------------------------------------------+
| grey item | grey item | grey item | grey item |
+-----------------------------------------------+
| dark item | dark item | dark item | dark item |
+-----------------------------------------------+
| grey item | grey item | grey item | grey item |
+-----------------------------------------------+
| dark item | dark item | dark item | dark item |
+-----------------------------------------------+
| grey item | grey item | grey item | grey item |
+-----------------------------------------------+
------------------ st2 name 2 -------------------
+-----------------------------------------------+
| grey item | grey item | grey item | grey item |
+-----------------------------------------------+
| dark item | dark item | dark item | dark item |
+-----------------------------------------------+
and its good.
But if items on st2 name is less than 4 in one line:
------------------ st2 name 1 -------------------
+-----------------------------------------------+
| grey item | grey item | grey item | grey item |
+-----------------------------------------------+
| dark item | dark item | dark item |
+-----------------------------------+
then next looks like this:
------------------ st2 name 1 -------------------
+-----------------------------------+
| grey item | grey item | grey item |
+-----------------------------------------------+
| dark item | dark item | dark item | dark item |
+-----------------------------------------------+
because cycle coutner is still on the fourth element.
How to reset cycle tag?

Answer 1

You can use cycle tag with silent keyword to declare the cycle but not produce the first value. By giving the cycle tag a name, using "as" you can insert the current value of the cycle wherever you’d like. Another cycle tag with name of the variable will move cycle to the next value independently. And divisibleby tag can be used to check for last in line item:
{% cycle 'clear tco1' 'tco' 'tco' 'tco2' 'clear tce1' 'tce' 'tce' 'tce2' as cellcls silent %}
{% for item in items %}
{% ifchanged item.st2 %}
<div class="clear"></div>
<div class="item-title">{{ item.get_st2 }}</div>
{% if not forloop.counter1|divisibleby:"4" %} {# im not tested it #}
{% cycle cellcls %}
{% endif %}
{% endifchanged %}
<div class="cell {{cellcls}}">{{ item.name }}</div>
{% cycle cellcls %}
{% endfor %}

Answer 2

Ugly, but it works:
{% cycle '1' '2' '3' '4' as cellcount silent %}
{% cycle 'tco1' 'tco' 'tco' 'tco2' 'tce1' 'tce' 'tce' 'tce2' as cellcls silent %}
{% for item in items %}
{% ifchanged item.st2 %}
{% if not forloop.first %}
{% if cellcount|add:0 == 2 %}
{% cycle cellcls %}{% cycle cellcls %}{% cycle cellcls %}
{% cycle cellcount %}{% cycle cellcount %}{% cycle cellcount %}
{% endif %}
{% if cellcount|add:0 == 3 %}
{% cycle cellcls %}{% cycle cellcls %}
{% cycle cellcount %}{% cycle cellcount %}
{% endif %}
{% if cellcount|add:0 == 4 %}
{% cycle cellcls %}
{% cycle cellcount %}
{% endif %}
{% endif %}
<div class="clear"></div>
<div class="item-title">{{ item.get_st2 }}</div>
{% endifchanged %}
<div class="cell {{ cellcls }}" style="{{ cellcount }}">{{ item.name }}</div>
{% cycle cellcls %}
{% cycle cellcount %}
{% endfor %}

Answer 3

I came across same problem and write small custom template tag (works in django 1.8):
from django import template
import itertools
register = template.Library()
class ResetCycleNode(template.Node):
def __init__(self, variable_name, cycle_node):
self.variable_name = variable_name
self.cycle_node = cycle_node
def render(self, context):
cycle_iter = itertools.cycle(self.cycle_node.cyclevars)
context.render_context[self.cycle_node] = cycle_iter
context[self.variable_name] = next(cycle_iter).resolve(context)
return ''
#register.tag
def reset_cycle(parser, token, escape=False):
args = token.split_contents()
if len(args) != 2:
raise TemplateSyntaxError("'reset_cycle' tag requires exactly one argument")
name = args[1]
if not hasattr(parser, '_namedCycleNodes'):
raise TemplateSyntaxError("No named cycles in template. '%s' is not defined" % name)
if name not in parser._namedCycleNodes:
raise TemplateSyntaxError("Named cycle '%s' does not exist" % name)
return ResetCycleNode(name, parser._namedCycleNodes[name])
And then use it in template like this:
{% cycle 'clear tco1' 'tco' 'tco' 'tco2' 'clear tce1' 'tce' 'tce' 'tce2' as cellclass silent %}
{% for item in items %}
{% ifchanged item.st2 %}
<div class="clear"></div>
<div class="item-title">{{ item.get_st2 }}</div>
{% reset_cycle cellclass %}
{% endifchanged %}
<div class="cell {{ cellclass }}{% cycle cellclass %}">{{ item.name }}</div>
{% endfor %}

Answer 4

This is an old question, but as of Django 1.11 there is a built-in tag, resetcycle that appears to do what OP wants.