To use the Joomla Media Manager in Custom Components
<script>
function useMediaManager(id)
{
if (!jQuery("#sbox-window").is(‘:visible’)) {
setTimeout(function(){useMediaManager(id);}, 200); //wait
return;
}

var f = jQuery(‘#sbox-window iframe’);
var ocfns, btns;

if(f[0] == undefined){
setTimeout(function(){useMediaManager(id);}, 200); //wait
return;
} else {
f.load(function(){//wait
var imageManager = f[0].contentWindow.ImageManager;
imageManager.onok = function()
{
setMedia(this.fields.url.get(‘value’), id);
};
});
}
}
function setMedia(url, id){
jQuery(‘#’+id).val(url);
}

</script>
<input type="text" name="image_url" value="<?php echo $row->image_url;?>" />
<a class="modal-button" title="Image" href="index.php?option=com_media&view=images&tmpl=component&e_name=tempimage" onclick="useMediaManager(‘image_url’); return false;" rel="{handler: ‘iframe’, size: {x: 570, y: 400}}">Add Image</a>