Safecracker and GWCODE Categories Checkboxes not staying checked

Question

Here is what I am trying to do.

I am using Safecracker to do the add/edit posting, but when the user click on a checkbox, then go to edit the posting, the check box is not there.

I am using Gwcode Categories Plugin, outputting my categories as checkboxes because it has more feature and flexibility then the built in safecracker categories tag

GWCode Categories

        <ul>
        {exp:gwcode_categories group_id="9"} 
        <li>
    <input type="checkbox"  id="categories" name="category[]" value="{cat_id}" {checked} />
 <span>{cat_name}</span>    
 </li>
 {/exp:gwcode_categories}
</ul>

but when I use Safecracker

<ul>
     {categories}
      <li>&lt;input type="checkbox" name="category[]" id="categories" value="{category_id}" {checked} /&gt; 
<span>{category_name}</span> </li>
{/categories}
</ul>

the checkbox is there. why I cant just used the {checked} in the Gwcode Categories and why does it have to be in {categories}{/categories}

here is the code that I have right now and trying to do with safecracker

{exp:gwcode_categories group_id="9"} 
    {if has_children && parent_id == '0' }
        <!-- parent with children -->
        <li class="checkbox checkbox_parent">  
            <span><b>{cat_name}</b></span>
        </li>
    {if:elseif depth == 2}
        <!-- child at second level -->
        <li class="checkbox">  
            <input type="checkbox" id="categories" name="category[]" value="{cat_id}" checked="{checked}" />
            <span>{cat_name}</span>
        </li>
    {if:elseif depth == 3}
        <!-- child at third level -->
        <li class="checkbox">  
            <input type="checkbox"  id="categories" name="category[]" value="{cat_id}" checked="{checked}" />
            <span>{cat_name}</span>
        </li>
    {if:else}
        <!-- parent with no children -->
        <li class="checkbox_parent_nochild">
            <input type="checkbox"  id="categories" name="category[]" value="{cat_id}" checked="{checked}"  /> 
            <span>{cat_name}</span>
        </li>
    {/if}
{/exp:gwcode_categories}

Answer 1

When within a SC form, GWcode Categories will not be aware of which categories are currently selected for the entry. You'll have to use Safecracker's {categories} loop.