Question

我想将文字放在图像上，所以我使用CSS来做到这一点。但是因为我使用Bootstap来制作它并且我觉得在CSS文件中放置绝对位置时我在调整大小时遇到了问题（文本没有居中），所以我制作了一个JQuery脚本来处理宽度变化，但它并没有＆＃ 39;工作

WidthChangeScript.js

if($(window).width() > 500){
$( "#FactionsWidthtoPos" ).css( "top","255px" );
}

的index.html

<head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>GrassCraft</title>
    <!----Bootstrap---->
    <link href="CSS/bootstrap.min.css" rel="stylesheet">
    <link href="CSS/textoverimage.css" rel="stylesheet">

</head>

<body>
    <nav class="navbar navbar-default navbar-fixed-top">
        <div class="container">


            <!-- Brand and toggle get grouped for better mobile display -->
            <div class="navbar-header">
                <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1" aria-expanded="false">
                    <span class="sr-only">Toggle navigation</span>
                    <span class="icon-bar"></span>
                    <span class="icon-bar"></span>
                    <span class="icon-bar"></span>
                </button>
                <a class="navbar-brand" href="#">Brand</a>
            </div>

<!-- Collect the nav links, forms, and other content for toggling -->
            <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
                <ul class="nav navbar-nav">
                    <li><a href="#">Forums</a></li>
                    <li class="dropdown">
                        <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">Shop<span class="caret"></span></a>
                        <ul class="dropdown-menu">
                            <li><a href="#">Factions Grass</a></li>
                            <li><a id="FctQu" href="#" >Factions Quartz</a></li>
                            <li role="separator" class="divider"></li>
                            <li><a href="#">How it works</a></li>
                        </ul>
                    </li>
                </ul>
                <form class="navbar-form navbar-left" role="search">
                    <div class="form-group">
                        <input type="text" class="form-control" placeholder="Search">
                    </div>
                    <button type="submit" class="btn btn-default">Submit</button>
                </form>
                <ul class="nav navbar-nav navbar-right">
                    <li><a href="#"></a></li>
                    <li class="dropdown">
                        <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">Dropdown <span class="caret"></span></a>
                        <ul class="dropdown-menu">
                            <li><a href="#">Action</a></li>
                            <li><a href="#">Another action</a></li>
                            <li><a href="#">Something else here</a></li>
                            <li role="separator" class="divider"></li>
                            <li><a href="#">Separated link</a></li>
                        </ul>
                    </li>
                </ul>
            </div><!-- /.navbar-collapse -->

        </div>
    </nav>
<!---Site body--->
    <div id="imgTop" class="imageBehindText">
        <img src="http://placehold.it/1920x800" class="img-responsive"  width="1980" height="800">  
        <h2 id="FactionsWidthtoPos" class="textOverImage" >Factions</h2>
    </div>
    <div class="placeHolderImage">
        <img src="http://placehold.it/1920x100" class="img-responsive"  width="1980" height="800">>
    </div>
    <div class="container">
        <div class="jumbotron">
            <h1 id="abtUs" > GrassCraft</h1> 
            <p id="abtUsTxt" >A new Factions server made by 2 young enthusiasts. Any financial support would mean alot</p> 
        </div>
    </div>






        <!----Botstrap required JQuery---->
    <script src="jquery.min.js"></script>

    <script src="JavaScript/bootstrap.min.js"></script>
    <script src="JavaScript/WidthChangeScript.js"></script>
</body>

textoverimage.css

 .imageBehindText { 
  position: relative; 
  width: 100%; /* for IE 6 */
  }

 .textOverImage { 
  position: absolute; 
  top: 100px;
  text-align: center;
  width: 100%; 
  color: #f0f8ff;
  text-decoration: underline;
  }
  .placeHolderImage {
  opacity: 0;

  }

这几乎是本网站的所有代码如果你知道我可以优化代码的任何方式，请说

Answer 1

您可以将代码置于jquery的resize事件处理程序中，如此

  $(document).ready(function(){
     function resize(){
       if($(window).width() > 500){
         if(!$( "#FactionsWidthtoPos" ).hasClass("something"))
           $( "#FactionsWidthtoPos" ).addClass("something");
       }else{
         if($( "#FactionsWidthtoPos" ).hasClass("something"))
           $( "#FactionsWidthtoPos" ).removeClass("something");
    }
  }
  resize();
  $(window).resize(function(){
    resize();
  });
});

你的css文件将包含一个新的类，如

.something{
   top : 255px;
}

您还可以使用媒体查询来更新您的css窗口大小更改，如此

@media only screen and (min-width: 500px) {
.textOverImage {
    top : 255px;
 }
}

当您的窗口大小为最小500px

时，此媒体查询会自动更新您的.textOverImage类

使用JQuery更改CSS顶部

1 个答案: