文字视差不起作用

时间:2013-09-27 18:26:31

标签: javascript html css parallax

我正在使用jquery.parallax-1.1.3.js来获得视差效果。 (网站:http://ianlunn.co.uk/plugins/jquery-parallax/

问题:它适用于css后台位置。这适用于背景图像,但不适用于我的HTML中的文本。

我想要的:在这个js文件中添加一些代码,允许我对html文本(H1,H2)使用视差效果。我更喜欢带身份证。因此,H1会有一个div,其ID与视差效果相关联。

这是js:

(function( $ ){
    var $window = $(window);
    var windowHeight = $window.height();

$window.resize(function () {
    windowHeight = $window.height();
});

$.fn.parallax = function(xpos, speedFactor, outerHeight) {
    var $this = $(this);
    var getHeight;
    var firstTop;
    var paddingTop = 0;

    //get the starting position of each element to have parallax applied to it      
    $this.each(function(){
        firstTop = $this.offset().top;
    });

    if (outerHeight) {
        getHeight = function(jqo) {
            return jqo.outerHeight(true);
        };
    } else {
        getHeight = function(jqo) {
            return jqo.height();
        };
    }

    // setup defaults if arguments aren't specified
    if (arguments.length < 1 || xpos === null) xpos = "50%";
    if (arguments.length < 2 || speedFactor === null) speedFactor = 0.1;
    if (arguments.length < 3 || outerHeight === null) outerHeight = true;

    // function to be called whenever the window is scrolled or resized
    function update(){
        var pos = $window.scrollTop();              

        $this.each(function(){
            var $element = $(this);
            var top = $element.offset().top;
            var height = getHeight($element);

            // Check if totally above or totally below viewport
            if (top + height < pos || top > pos + windowHeight) {
                return;
            }

            $this.css('backgroundPosition', xpos + " " + Math.round((firstTop - pos) * speedFactor) + "px");

        });
    }       

    $window.bind('scroll', update).resize(update);
    update();
};
})(jQuery);

这是如何从html调用js:

    <script type="text/javascript" src="js/jquery.parallax-1.1.3.js"></script>
<script type="text/javascript">
$(document).ready(function(){

//.parallax(xPosition, speedFactor, outerHeight) options:
//xPosition - Horizontal position of the element
//inertia - speed to move relative to vertical scroll. Example: 0.1 is one tenth the speed of scrolling, 2 is twice the speed of scrolling
//outerHeight (true/false) - Whether or not jQuery should use it's outerHeight option to determine when a section is in the viewport
$('#third').parallax("50%", 0.5);

})
</script>

你给div一个ID。你给这个Div一个背景图像。您将ID连接到上面的视差效果。我想做同样的事情,但后来用H1。

0 个答案:

没有答案