title: Set default value for checkboxes in Drupal
body: <p>I'm trying to set a <code>#default_value</code> on my D7 form, but it's not working... This is my array:</p>
  
  <pre><code>'thema_30fdc789-1453-4efa-93d6-123cab52206e' =&gt; 
      array
        '#type' =&gt; string 'checkboxes' (length=10)
        '#title' =&gt; string 'What kind of fiches??' (length=42)
        '#options' =&gt; 
          array
            'create' =&gt; string 'New fiches'     (length=13)
            'update' =&gt; string 'Updated fiches' (length=13)
            'delete' =&gt; string 'Deleted fiches' (length=13)
  </code></pre>
  
  <p>After editing this form with this line:</p>
  
  <pre><code>$form['thema_30fdc789-1453-4efa-93d6-123cab52206e']['#default_values']= 
          array('create' =&gt; 'Nieuwe fiches', 'update' =&gt; 'Update fiches', 'delete' =&gt; 'Delete fiches');
  </code></pre>
  
  <p>I get this <code>var_dump</code>:</p>
  
  <pre><code> 'thema_30fdc789-1453-4efa-93d6-123cab52206e' =&gt; 
      array
        '#type' =&gt; string 'checkboxes' (length=10)
        '#title' =&gt; string 'What kind of fiches??' (length=42)
        '#options' =&gt; 
          array
            'create' =&gt; string 'Newfiches'      (length=13)
            'update' =&gt; string 'Updated fiches' (length=13)
            'delete' =&gt; string 'Deleted fiches' (length=13)
        '#default_values' =&gt; 
          array
            'create' =&gt; string 'Newfiches'      (length=13)
            'update' =&gt; string 'Updated fiches' (length=13)
            'delete' =&gt; string 'Deleted fiches' (length=13)
  </code></pre>
  
  <p>So, the <code>hook_form_alter</code> did his job. Nevertheless, the checkboxes aren't checked on when reloading the page... What do I need to do to make sure they are checked on?</p>