How do I use ViewScripts on Zend_Form File Elements?

Question

I am using this ViewScript for my standard form elements:

<div class="field" id="field_<?php echo $this->element->getId(); ?>">
   <?php if (0 < strlen($this->element->getLabel())) : ?>
      <?php echo $this->formLabel($this->element->getName(), $this->element->getLabel());?>
   <?php endif; ?>
   <span class="value"><?php echo $this->{$this->element->helper}(
      $this->element->getName(),
      $this->element->getValue(),
      $this->element->getAttribs()
   ) ?></span>
   <?php if (0 < $this->element->getMessages()->length) : ?>
       <?php echo $this->formErrors($this->element->getMessages()); ?>
   <?php endif; ?>
   <?php if (0 < strlen($this->element->getDescription())) : ?>
      <span class="hint"><?php echo $this->element->getDescription(); ?></span>
   <?php endif; ?>
</div>

Trying to use that ViewScript alone results in an error:

Exception caught by form: No file decorator found... unable to render file element

Looking at this FAQ revealed part of my problem, and I updated my form element decorators like this:

'decorators' => array(
   array('File'),
   array('ViewScript', array('viewScript' => 'form/field.phtml'))
)

Now it's rendering the file element twice, once within my view script, and extra elements with the file element outside my view script:

<input type="hidden" name="MAX_FILE_SIZE" value="8388608" id="MAX_FILE_SIZE" />
<input type="hidden" name="UPLOAD_IDENTIFIER" value="4b5f7335a55ee" id="progress_key" />
<input type="file" name="upload_file" id="upload_file" />
<div class="field" id="field_upload_file">
    <label for="upload_file">Upload File</label>
    <span class="value"><input type="file" name="upload_file" id="upload_file" /></span>
</div>

Any ideas on how to handle this properly with a ViewScript?

---

UPDATE: Based on Shaun's solution, here's my final code:

Form Element:

$this->addElement('file', 'upload_file', array(
    'disableLoadDefaultDecorators' => true,
    'decorators' => array('File', array('ViewScript', array(
        'viewScript' => '_form/file.phtml',
        'placement' => false,
    ))),
    'label' => 'Upload',
    'required' => false,
    'filters' => array(),
    'validators' => array(array('Count', false, 1),),
));

View Script:

<?php
$class .= 'field ' . strtolower(end(explode('_',$this->element->getType())));
if ($this->element->isRequired()) {
    $class .= ' required';
}
if ($this->element->hasErrors()) {
    $class .= ' errors';
}
?>
<div class="<?php echo $class; ?>" id="field_<?php echo $this->element->getId(); ?>">
    <?php if (0 < strlen($this->element->getLabel())): ?>
        <?php echo $this->formLabel($this->element->getFullyQualifiedName(), $this->element->getLabel());?>
    <?php endif; ?>
    <span class="value"><?php echo $this->content; ?></span>
    <?php if ($this->element->hasErrors()): ?>
        <?php echo $this->formErrors($this->element->getMessages()); ?>
    <?php endif; ?>
    <?php if (0 < strlen($this->element->getDescription())): ?>
        <p class="hint"><?php echo $this->element->getDescription(); ?></p>
    <?php endif; ?>
</div>

Answer 1

The answer is relatively simple as it happens. All you need do is specify the File decorator first, create a specific view script for the file input and specify false for the placement in the viewScript decorator arguments, this will effectively inject the output from the File decorator into the viewScript decorator e.g.

$element->setDecorators(array('File', array('ViewScript', array('viewScript' => 'decorators/file.phtml', 'placement' => false))));

Then in the new file element view script you simply echo $this->content in the script where you'd like the file input markup to be placed. Here's an example from a recent project, so ignore the markup if it looks a little odd, hopefully it will illustrate the point.

<label for="<?php echo $this->element->getName(); ?>" class="element <?php if ($this->element->hasErrors()): ?> error<?php endif; ?>" id="label_<?php echo $this->element->getName(); ?>"> 
<span><?php echo $this->element->getLabel(); ?></span>

<?php echo $this->content; ?>

<?php if ($this->element->hasErrors()): ?>

    <span class="error">
        <?php echo $this->formErrors($this->element->getMessages()); ?>
    </span>

<?php endif; ?>

</label>

When rendered you will see this html for the element

<label for="photo" class="element" id="label_photo"> 
<span>Photo</span>

<input type="hidden" name="MAX_FILE_SIZE" value="6291456" id="MAX_FILE_SIZE">
<input type="file" name="photo" id="photo">

</label>