M端滾動異步加載數據

var currentPage =1; //默認頁
var pages = {:$pageNum:}; //總頁數
function nextPage(){
	if (pages == 0){
		return;
	}
	currentPage++;
	if(currentPage>pages){
		jQuery('#no_more').show();
		return;
	}
	if(currentPage>1){
		 jQuery('.loading').show();
	}
	var response = $.ajax({
		type: "POST",
		url: "/index.php?m=default&c=index&a=ghomeAjax",
		data: {
					 "page" : currentPage,
			   },
		 success: function(data){
			jQuery('.com_list ul').append(data);
			jQuery('.loading').hide();
		 },
		 async: true
	 });
 }
//滾動加載
$(window).scroll(function(){
	if (getScrollTop() + getClientHeight() >= getScrollHeight()){ 
		nextPage();
	}
	lodingImg();
});

//圖片預加載
function lodingImg(){
	$('#topbanner img,.com_list img').each(function(){
		if($(this).offset().top<=$(document).scrollTop()+$(window).height() 
		&& $(this).offset().top>=$(document).scrollTop()) {
			var url = $(this).attr('loding'),
			img = $(this).attr('src');
			if(img!=url){
				$(this).attr({src:url,alt:''}).css({opacity:0}).animate({opacity:1},500);
			}
		}
	});
}

lodingImg();//加載圖片
//窗口改變大小加載
$(window).resize(function(){    
	lodingImg();//加載圖片
});

//獲取滾動條當前的位置 
function getScrollTop(){ 
	var scrollTop = 0; 
	if (document.documentElement && document.documentElement.scrollTop){ 
		scrollTop = document.documentElement.scrollTop; 
	}else if (document.body) { 
		scrollTop = document.body.scrollTop; 
	} 
	return scrollTop; 
} 

//獲取當前可是範圍的高度 
function getClientHeight(){ 
	var clientHeight = 0; 
	if (document.body.clientHeight && document.documentElement.clientHeight){ 
		clientHeight = Math.min(document.body.clientHeight, document.documentElement.clientHeight); 
	} else { 
		clientHeight = Math.max(document.body.clientHeight, document.documentElement.clientHeight); 
	} 
	return clientHeight; 
} 

//獲取文檔完整的高度 
function getScrollHeight(){ 
	return Math.max(document.body.scrollHeight, document.documentElement.scrollHeight); 
}

public function glistAjax(){
	$pagesize = 6;
	$page = isset($_POST['page']) ? (int)$_POST['page'] : 1;
	
	$limit = ($page-1)*$pagesize;
	$limit.=",".$pagesize;
	$order = "add_time desc";
	
	$where = "";
	$list = $this->index->get_goods_list($where,$data='*',$limit,$order);
	
	$httpRequestTools = new HttpRequest;
	if(!$list){
		if($httpRequestTools->isAjax()){
			echo "";
			exit;
	    }else{
			return "";
	    }
	}
	$html = template('goodslist','ajax_goods_list1','default',true,array("list"=>$list));
	if($httpRequestTools->isAjax()){
	    echo $html;
	    exit;
	}else{
	    return $html;
	}
}