jquery实现居中弹出层代码

/* 
弹出窗口定位到浏览器中间 
1. show(options{ 
height:高度 
width:宽度 
speed:渐显时间 默认0 
container:包含的html内容的jquery对象 
model:是否是模态窗口，默认true，模态对话框就是在弹层下面在覆盖遮罩层，参考上篇文章Overlay实现 
}) 
2. close(speed:淡出时间 默认0) 
*/ 
Q.Panel = function() { 
var self = this; 
self._resetPosition = function() { 
self._container.css("top", self._getTop()); 
self._container.css("left", self._getLeft()); 
}; 
self._getTop = function() { 
return Q.bom.scrollY() + (Q.bom.windowHeight() - self._options.height) / 2; 
}; 
self._getLeft = function() { 
return (Q.dom.pageWidth() - self._options.width) / 2; 
}; 
self.show = function(options) { 
self._options = $.extend({ 
width: 350, 
height: 200, 
opacity: 0.5, 
model: true, 
speed: 0 
}, options || {}); 
self._container = self._options.container; 
var css = { 
'width': self._options.width, 
'height': self._options.height, 
'z-index': Q.Overlay.zindex, 
'position': 'absolute', 
'left': self._getLeft(), 
'top': self._getTop(), 
'display': 'none' 
}; 
self._container.css(css); 
if (self._options.model) { 
self._overlay = new Q.Overlay(self._options.opacity); 
self._overlay.show(); 
} 
$(window).scroll(self._resetPosition); 
$(window).resize(self._resetPosition); 
$(document.body).append(self._container); 
self._container.fadeIn(self._options.speed); 
Q.Overlay.zindex++; //没弹出一次就递增，防止多个弹层重叠 
}; 
self.close = function(speed) { 
$(window).unbind('resize', self._resetPosition); 
$(window).unbind('scroll', self._resetPosition); 
self._container.fadeOut(speed || 0, function() { 
self._container.remove(); 
if (self._options.model) { 
self._overlay.close(); 
} 
}); 
}; 
};

这里居中是通过js控制的,下面是几个用这个剧中Panel实现的通用对话框

/*弹出自定义隐藏框 
<div id="league" style="display:none"> 
<button class="close" >close</button> 
</div> 
Q.showPanel("league", function(panel, container) { 
container.find(".close").click(function() { 
panel.close(); 
} 
); 
*/ 
Q.showPanel = function(containerId, registerEventCallback) { 
var container = $("#" + containerId); 
var height = container.height(); 
var width = container.width(); 
container = container.clone(true); 
var options = { height: height, width: width, container: container }; 
var panel = new Q.Panel(); 
registerEventCallback(panel, container); 
panel.show(options); 
}; 
/*弹出窗口，从url加载窗体html片段*/ 
Q.openWindow = function(url, data, registerEventCallback) { 
$.get(url, data, function(html) { 
var panelDiv = $(html); 
panelDiv.hide(); 
$(document.body).append(panelDiv); 
var options = { height: panelDiv.height(), width: panelDiv.width(), container: panelDiv }; 
var panel = new Q.Panel(); 
registerEventCallback(panel, panelDiv); 
panel.show(options); 
}); 
} 
/*提示框，3秒后自动淡出*/ 
Q.tips = function(msg) { 
var html = '<div class="gu_layer w330">' + 
'<div class="gu_layer_main">' + 
'<h2><img class="icon_layer_corner" alt="" src="http://res.fetionpic.com/img/blank/spacer.gif">提示</h2>' + 
'<p class="gu_layer_txt">' + msg + '</p>' + 
'<div class="gu_layer_btn"></div>' + 
'</div></div>' 
var container = $(html); 
container.hide(); 
$(document.body).append(container); 
var panel = new Q.Panel(); 
panel.show({ container: container, height: container.height(), width: container.width() ,speed:500}); 
setTimeout(function() { panel.close(500); }, 3000); 
}; 
/*提示框*/ 
Q.alert = function(msg) { 
var html = '<div class="gu_layer w330">' + 
'<div class="gu_layer_main">' + 
'<h2><img class="icon_layer_corner" alt="" src="http://res.fetionpic.com/img/blank/spacer.gif"><a class="btn_tit_close" href="">关闭</a>提示</h2>' + 
'<p class="gu_layer_txt">' + msg + '</p>' + 
'<div class="gu_layer_btn"><a class="btn_org" href="">确 定</a></div>' + 
'</div></div>' 
var container = $(html); 
container.hide(); 
$(document.body).append(container); 
var panel = new Q.Panel(); 
container.find(".btn_tit_close").click(function() { 
panel.close(); 
return false; 
}); 
container.find(".btn_org").click(function() { 
panel.close(); 
return false; 
}); 
panel.show({ container: container, height: container.height(), width: container.width() }); 
}; 
/*确认框 cancel回调为可选*/ 
Q.confirm = function(title, msg, yes, cancel) { 
var html = '<div class="gu_layer w330">' + 
'<div class="gu_layer_main">' + 
'<h2><img class="icon_layer_corner" alt="" src="http://res.fetionpic.com/img/blank/spacer.gif"><a class="btn_tit_close" href="">关闭</a>' + title + '</h2>' + 
'<p class="gu_layer_txt">' + msg + '</p>' + 
'<div class="gu_layer_btn"><a class="btn_org" href="">确 定</a><a class="btn_gray" href="">取 消</a></div>' + 
'</div></div>' 
var container = $(html); 
container.hide(); 
$(document.body).append(container); 
var panel = new Q.Panel(); 
container.find(".btn_tit_close").click(function() { 
panel.close(); 
return false; 
}); 
container.find(".btn_gray").click(function() { 
if (cancel) 
cancel(); 
panel.close(); 
return false; 
}); 
container.find(".btn_org").click(function() { 
if (yes) 
yes(); 
panel.close(); 
return false; 
}); 
panel.show({ container: container, height: container.height(), width: container.width() }); 
};