如何使用Javascript切换基于图像URL的背景图像

时间:2013-02-19 11:59:49

标签: javascript image toggle background-image

我想根据点击的DIV的网址更改点击背景图片

我的逻辑如下:

当用户点击div

 {

    If (Background URL = x)
    {
       change background url property to y
    }
    else
    {
       change background url property to x
    }
 }

这是我使用的代码

HTML:

<div id="AccordionContainer" class="AccordionContainer">

    <div onclick="runAccordion(1);changeArrow(1)">
        <div class="AccordionTitle" id="Accordion1Title" onselectstart="return false;" onclick="changeArrow(1);" >
            Instructions
        </div>
    </div>

    <div id="Accordion1Content" class="AccordionContent">  
        <p>Enter in your search parameters</p>
    </div>

    <div onclick="runAccordion(2);">
        <div class="AccordionTitle" id="Accordion2Title" onselectstart="return false;" onclick="changeArrow(2);" >
            Colour
        </div>
    </div>

    <div id="Accordion2Content" class="AccordionContent">  
        [wpv-control field="cultivar-category" type="checkboxes" values="Dark Red" url_param="cultivar-category"]
    </div>

</div>

的Javascript

function changeArrow(index)
{
    var arrowID = "Accordion" + index + "Title";    

    var img = document.getElementById(arrowID),
    style = img.currentStyle || window.getComputedStyle(img, false),
    bi = style.backgroundImage.slice(4, -1);


if (bi = "http://www.hadecobulbs.com/wp-content/themes/blankslate/img/accordian-title.png")
{
    document.getElementById(arrowID).style.background="url(http://www.hadecobulbs.com/wp-content/themes/blankslate/img/accordian-title-up.png) no-repeat scroll 0 0 transparent";
}
else
{
    document.getElementById(arrowID).style.background="url(http://www.hadecobulbs.com/wp-content/themes/blankslate/img/accordian-title.png) no-repeat scroll 0 0 transparent";
}

}

然而,当我点击手风琴(索引)标题Div时,图像会在第一次单击时发生变化,但是当我再次单击时图像不会变回。为什么会这样呢?我在这里缺少什么?

1 个答案:

答案 0 :(得分:0)

您可以使用this传递元素本身,而不是将数字传递给函数,这意味着您可以大幅减少编写的代码量。

像你这样在你的div上调用这个函数

<div class="background_one" onClick="changeArrow(this)"> </div>

使用@ d4rkpr1nc3的注释设置你的css类来改变背景图像

.background_one {
width:188px;
height:32px;
background-image:url('wp-content/themes/blankslate/img/accordian-title-up.png');
}

.background_two {
width:188px;
height:32px;
background-image:url('wp-content/themes/blankslate/img/accordian-title.png');
}

然后在你的函数中做这样的事情

function changeArrow(element){

  var arrow = element;

    if(arrow.className == 'background_one'){

      arrow.className = 'background_two';

    } else {

      arrow.className = 'background_one';

    }

}

这是一个jsfiddle - http://jsfiddle.net/QwELf/