Renders all empty hidden fields that have been added to ViewHelperVariableContainer
@see \Neos\FluidAdaptor\ViewHelpers\Form\AbstractFormFieldViewHelper::renderHiddenFieldForEmptyValue()

@return string
198672
protected function renderEmptyHiddenFields()
    {
        $result = '';
        if ($this->viewHelperVariableContainer->exists(\Neos\FluidAdaptor\ViewHelpers\FormViewHelper::class, 'emptyHiddenFieldNames')) {
            $emptyHiddenFieldNames = $this->viewHelperVariableContainer->get(\Neos\FluidAdaptor\ViewHelpers\FormViewHelper::class, 'emptyHiddenFieldNames');
            foreach ($emptyHiddenFieldNames as $hiddenFieldName => $disabled) {
                $disabledAttribute = $disabled !== false ? ' disabled="' . htmlspecialchars($disabled) . '"' : '';
                $result .= '<input type="hidden" name="' . htmlspecialchars($hiddenFieldName) . '" value=""' . $disabledAttribute . ' />' . chr(10);
            }
        }
        return $result;
    }
62994
public function renderHiddenPopover()
    {
        $this->parts['{hidden}'] = '';

        return implode($this->hiddenDelimiter ?? $this->delimiter, $this->getSpoiledItems());
    }
648123
protected function getRawValue()
    {
        $value = null;

        $data = &$this->getForm()->getFormData();

        if ($this->autocomplete) {
            $id = $this->id;
            if (isset($data[$id]) && $data[$id] != '') {
                $value = $data[$id];
            }
        } else {
            if (isset($data[$this->id . '_nonce'])) {
                $id = $data[$this->id . '_nonce'];
                if (isset($data[$id]) && $data[$id] != '') {
                    $value = $data[$id];
                }
            }
        }

        return $value;
    }
346236
protected function createHidden($name, $value = null)
    {
        $field = Former::hidden($this->inputName($name))->class('input-'.$name);
        if ($value) {
            if (!is_scalar($value)) {
                $value = json_encode($value);
            }
            $field->forceValue($value);
        }

        return $field->render();
    }
16604
public function getRenderValue()
    {
        $name = $this->getName();
        $defaultValue = $this->getDefaultValue();
        $bean = $this->getBean();
        $value = "";

        if ($this->isCreate()) {

            // Create Page
            // Use Default Value if not null
            if ($this->value !== null) {
                $value = $this->value;
            } else if ($defaultValue !== null) {
                $value = $defaultValue;
            }

        } else {

            // Edit Page
            if ($this->getFieldRelation() == Field::MANY_TO_MANY) {
                // Many to many, Value list
                $keyName = "shared". ucfirst($name) . "List";

                $relatedBeans = $bean->{$keyName};
                $value = [];

                foreach ($relatedBeans as $relatedBean) {
                    $value[$relatedBean->id] = $relatedBean->id;
                }

            } else {

                // Single Value
                if ($this->isOverwriteValue() && $this->value !== null) {
                    // Use the value set by user.
                    $value = $this->value;
                } else {
                    // Use the value from Database
                    $value = $this->getFieldType()->beforeRenderValue($bean->{$name});

                    // Escape the html
                    $value = htmlspecialchars($value);
                }
            }

        }

        return $value;
    }
807741
public function render()
    {
        $name = $this->getName();
        $this->registerFieldNameForFormTokenGeneration($name);

        $this->tag->addAttribute('name', $name);

        $value = $this->getValueAttribute();

        if ($value !== null) {
            $this->tag->addAttribute('value', $value);
        }

        $this->addAdditionalIdentityPropertiesIfNeeded();
        $this->setErrorClassAttribute();

        return $this->tag->render();
    }
1163260
@Nullable
  public final String getHiddenFieldName ()
  {
    final String sFieldName = getName ();
    if (StringHelper.hasNoText (sFieldName))
      return null;

    return HIDDEN_FIELD_PREFIX + sFieldName;
  }
504899
public function render()
    {
        $returnValue = $this->renderLabel();
        
        $checkAll = false;
        if (isset($this->attributes['checkAll'])) {
            $checkAll = (bool) $this->attributes['checkAll'];
            unset($this->attributes['checkAll']);
        }
        $i = 0;
        $checked = 0;
        $returnValue .= '<div class="form_radlst form_checklst plain">';
        $readOnlyOptions = $this->getReadOnly();
        foreach ($this->options as $optionId => $optionLabel) {
            $readOnly = isset($readOnlyOptions[$optionId]);
            if($readOnly){
                $returnValue .= '<div class="grid-row readonly">';
            }else{
                $returnValue .= '<div class="grid-row">';
            }

            $returnValue .= '<div class="col-1">';
            $returnValue .= "<input type='checkbox' value='{$optionId}' name='{$this->name}_{$i}' id='{$this->name}_{$i}' ";
            $returnValue .= $this->renderAttributes();

            if ($readOnly) {
                $returnValue .= "disabled='disabled' readonly='readonly' ";
            }

            if (in_array($optionId, $this->values)) {
                $returnValue .= " checked='checked' ";
                $checked ++;
            }
            $returnValue .= ' />';
            $returnValue .= '</div><div class="col-10">';
            $returnValue .= "<label class='elt_desc' for='{$this->name}_{$i}'>" . _dh($optionLabel) . "</label>";
            $returnValue .= '</div><div class="col-1">';
            if ($readOnly) {
                $readOnlyReason = $readOnlyOptions[$optionId];
                if(!empty($readOnlyReason)){
                    $returnValue .= '<span class="tooltip-trigger icon-warning" data-tooltip="~ .tooltip-content" data-tooltip-theme="info"></span><div class="tooltip-content">'._dh($readOnlyReason).'</div>';
                }
            }
            $returnValue .= '</div></div>';
            $i ++;
        }
        $returnValue .= "</div>";
        
        // add a small link
        if ($checkAll) {
            if ($checked == (count($this->options) - count($readOnlyOptions))) {
                $returnValue .= "<span class='checker-container'><a id='{$this->name}_checker' class='box-checker box-checker-uncheck' href='#'>" . __('Uncheck All') . "</a></span>";
            } else {
                $returnValue .= "<span class='checker-container'><a id='{$this->name}_checker' class='box-checker' href='#'>" . __('Check All') . "</a></span>";
            }
        }
        
        return (string) $returnValue;
    }
420543
public function renderHiddenSpoiler()
    {
        $options = ArrayHelper::merge([
            'id' => $this->button['id'] . '-body',
            'tag' => 'span',
            'value' => implode($this->hiddenDelimiter ?? $this->delimiter, $this->getSpoiledItems()),
            'class' => 'collapse',
            'data-spoiler-body' => true,
        ], $this->hidden);

        $this->parts['{hidden}'] = Html::tag(ArrayHelper::remove($options, 'tag'), ArrayHelper::remove($options, 'value'), $options);
    }
569814
protected function renderArray()
    {
        if (count($this->variablesToRender) === 1) {
            $variableName = current($this->variablesToRender);
            $valueToRender = isset($this->variables[$variableName]) ? $this->variables[$variableName] : null;
            $configuration = isset($this->configuration[$variableName]) ? $this->configuration[$variableName] : [];
        } else {
            $valueToRender = [];
            foreach ($this->variablesToRender as $variableName) {
                $valueToRender[$variableName] = isset($this->variables[$variableName]) ? $this->variables[$variableName] : null;
            }
            $configuration = $this->configuration;
        }
        return $this->transformValue($valueToRender, $configuration);
    }
316292
public function form_hidden($params) {
        if (!isset($params['field'])) {
            throw new \UnexpectedValueException("The field parameter is required.");
        }
        $value = isset($params['value']) ? $params['value'] : null;
        $attributes = isset($params['attrs']) ? $params['attrs'] : array();
        return Form::hidden($params['field'], $value, $attributes);
    }
165865
public function hiddenFields($hiddenFields = null) {
		if (empty($hiddenFields)) {
			return null;
		}

		if (!is_array($hiddenFields)) {
			$hiddenFields = [$hiddenFields];
		}

		$result = '';
		$options = ['type' => 'hidden'];
		foreach ($hiddenFields as $hiddenField) {
			$result .= $this->input($hiddenField, $options);
			if ($this->isFieldError($hiddenField)) {
				$result .= $this->Html->div(
					'form-group has-error',
					$this->error($hiddenField, null, ['class' => 'help-block'])
				);
			}
		}

		return $result;
	}
1076397
protected function getUnrenderedFields()
    {
        $unrenderedFields = [];

        foreach ($this->fields as $field) {
            if (!$field->isRendered()) {
                $unrenderedFields[] = $field;
                continue;
            }
        }

        return $unrenderedFields;
    }
1053686
public function render()
    {
        $name = $this->getName();
        if ($this->hasArgument('multiple')) {
            $name .= '[]';
        }

        $this->tag->addAttribute('name', $name);

        $options = $this->getOptions();
        $this->tag->setContent($this->renderOptionTags($options));

        $this->addAdditionalIdentityPropertiesIfNeeded();
        $this->setErrorClassAttribute();

        // register field name for token generation.
        // in case it is a multi-select, we need to register the field name
        // as often as there are elements in the box
        if ($this->hasArgument('multiple') && $this->arguments['multiple'] !== '') {
            $this->renderHiddenFieldForEmptyValue();
            for ($i = 0; $i < count($options); $i++) {
                $this->registerFieldNameForFormTokenGeneration($name);
            }
        } else {
            $this->registerFieldNameForFormTokenGeneration($name);
        }

        return $this->tag->render();
    }
1236193
protected function _render_select($data, $current_value)
    {
        if (isset($data['options'])) {
            $options = $data['options'];
            unset($data['options']);
        } elseif (isset($data['values'])) {
            $options = $data['values'];
            unset($data['values']);
        } else {
            throw new MissingFieldException('values');
        }

        if (isset($data['all'])) {
            if ($data['all']) {
                $options = array_merge(['' => $data['all']], $options);
            }
            unset($data['all']);
        } else {
            $options = array_merge(['' => $this->_select_all_text], $options);
        }

        $r = PHP_EOL . '  <select';
        foreach (['id', 'name', 'class'] as $attr) {
            if (isset($data[$attr])) {
                $r .= " $attr=\"$data[$attr]\"";
                unset($data[$attr]);
            }
        }

        foreach ($data as $attr => $value) {
            $r .= " $attr=\"" . htmlspecialchars($data[$attr]) . '"';
        }

        $r .= '>' . PHP_EOL;

        foreach ((array)$options as $value => $label) {
            $r .= '    <option value="' . (is_numeric($value) ? $value : htmlspecialchars($value)) . '"';
            /** @noinspection TypeUnsafeComparisonInspection */

            $selected = false;
            if ($value === '') {
                if ($current_value === null || $current_value === '') {
                    $selected = true;
                }
            } elseif ($value === '0' || $value === 0) {
                if ($current_value === '0' || $current_value === 0) {
                    $selected = true;
                }
            } elseif ((string)$value === (string)$current_value) {
                $selected = true;
            }

            if ($selected) {
                $r .= ' selected';
            }
            $r .= '>' . htmlspecialchars($label) . '</option>' . PHP_EOL;
        }
        $r .= '  </select>' . PHP_EOL;

        return $r;
    }
669282
public function renderToggleButton()
    {
        if ($this->toggleButton !== null) {
            $tag   = ArrayHelper::removeValue($this->toggleButton, 'tag', 'button');
            $label = ArrayHelper::removeValue($this->toggleButton, 'label', 'Show');
            if ($tag === 'button' && !isset($this->toggleButton['type'])) {
                $this->toggleButton['type'] = 'button';
            }
            $this->toggleButton['data-reveal-id'] = $this->getId();
            return \CHtml::tag($tag, $this->toggleButton, $label);
        } else {
            return null;
        }
    }
1033274
public function render() {
		// execute callback if we have one first
		if ( is_closure( $this->value ) ) {
			ob_start(); $return = call_user_func( $this->value ); $this->value = ob_get_clean().$return;
		}
		return '<'.$this->name.static::attr( $this->attr ).
			( !is_null( $this->value ) ? '>'.$this->value.'</'.$this->name.'>' : ' />' );
	}