Magento: Displaying Price filter of catgeory or layer filter in magento programmatically

If you need to display layer price filter, we can display in 2 type, one is calling default block but issue is some time price will not display if you click price filter or if cache is disabled
Default Price filter

public function priceHtmlnav($maincategoryId) {
$html ='';
$layer = Mage::getModel('catalog/layer');
$category = Mage::getModel('catalog/category')->load($maincategoryId);
if ($category->getId()) {
$origCategory = $layer->getCurrentCategory();
$layer->setCurrentCategory($category);
}
$r=Mage::getModel('catalog/layer_filter_price')
->setLayer($layer);

$range = $r->getPriceRange();
$dbRanges = $r->getRangeItemCounts($range);
$data = array();

foreach ($dbRanges as $index=>$count) {
$data[] = array(
'label' => $this->_renderItemLabel($range, $index),
'value' => $index . ',' . $range,
'count' => $count,
);
}
foreach($data as $d){
$t=str_replace('<span class="price">', "", $d['label']);
$t=str_replace('</span>', "", $t);
$html .= '<li><a href="'.$category->getUrl().'?price='.$d['value'].'">'.$t.'</a></li>';
}


return $html;
}
and call this funtion

$html=''
$html .= '
<h4>Price</h4>
<ul class="price_grid">';
$html .= $this->priceHtmlnav($maincategoryId);
$html .='</ul>';
echo $html; 

To over the default issue i write custom code so even if cache is disabled the link will display

<?php
define('MAGENTO', realpath(dirname(__FILE__)));
require_once MAGENTO . '/app/Mage.php';
Mage::app();
$storename='default';
function _renderItemLabel($range, $value)
{
$store = Mage::app()->getStore();
$fromPrice = $store->formatPrice(($value-1)*$range);
$toPrice = $store->formatPrice($value*$range);

return Mage::helper('catalog')->__('%s - %s', $fromPrice, $toPrice);
}


$html = '<h4>Price</h4>
<ul class="price_grid">';


$layer = Mage::getModel('catalog/layer');
$category = Mage::getModel('catalog/category')->load(6);
if ($category->getId()) {
$origCategory = $layer->getCurrentCategory();
$layer->setCurrentCategory($category);
}


$r=Mage::getModel('catalog/layer_filter_price')
->setLayer($layer);

$range = $r->getPriceRange();
$dbRanges = $r->getRangeItemCounts($range);
$data = array();

foreach ($dbRanges as $index=>$count) {
$data[] = array(
'label' => _renderItemLabel($range, $index),
'value' => $index . ',' . $range,
'count' => $count,
);
}
foreach($data as $d){
$html .= '<li><a href="'.$category->getUrl().'?price='.$d['value'].'">'.$d['label'].'</a></li>';
}
$html .='</ul>';

echo $html;

?>