如何使用 JQuery 使图像具有不透明度脉冲

Question

我试图让图像在一段时间内平滑地改变不透明度。这是我的代码。

<script type="text/javascript">
pulsem(elementid){
    var element = document.getElementById(elementid)
    jquery(element).pulse({opacity: [0,1]}, 
{    duration: 100, // duration of EACH individual animation    
     times: 3, // Will go three times through the pulse array [0,1]   
     easing: 'linear', // easing function for each individual animation    
     complete: function() {        alert("I'm done pulsing!");    }
})
</script>


<a href="city.htm"><img src="waterloo.png" onmouseover="javascript:pulsem("waterloo")" border="0" class="env" id="waterloo"/></a>

另外，有没有一种方法可以自动发生这种情况，而不需要鼠标悬停？谢谢。

Answer 1

我假设您的代码用于 jQuery 脉冲插件： http: //james.padolsey.com/javascript/simple-pulse-plugin-for-jquery/

如果上面的代码不起作用，请将“jquery”修复为“jQuery”。

要在页面加载时启动它，只需执行以下操作：

jQuery(function() {
jQuery('#yourImageId').pulse({
    opacity: [0,1]
}, {
     duration: 100, // duration of EACH individual animation
     times: 3, // Will go three times through the pulse array [0,1]
     easing: 'linear', // easing function for each individual animation
     complete: function() {
         alert("I'm done pulsing!");
    }
});

向您的图像添加一个 id 即可。
});

Answer 2

要根据自己的意愿触发动画：

pulsate( $('#waterloo') );

修改代码以持续脉动（不确定这是否是您想要的）-脉动效果被降级为它自己的函数，因此您可以直接调用它或在事件处理程序中调用它

<script type="text/javascript">
  $(function() { // on document ready
     $('#waterloo').hover( //hover takes an over function and out function
       function() {
         var $img = $(this);
         $img.data('over', true); //mark the element that we're over it
         pulsate(this); //pulsate it
       },
       function() {
          $(this).data('over', false); //marked as not over
       });
  });

 function pulsate(element) {
    jquery(element).pulse({opacity: [0,1]}, // do all the cool stuff
        {    duration: 100, // duration of EACH individual animation    
             times: 3, // Will go three times through the pulse array [0,1]   
             easing: 'linear', // easing function for each individual animation    
             complete: function() {  
                 if(  $(this).data('over') ){ // check if it's still over (out would have made this false)
                     pulsate(this); // still over, so pulsate again
                 }
         }});
  } 

<a href="city.htm"><img src="waterloo.png" border="0" class="env" id="waterloo"/></a>

注意 - 要触发事件，您可以使用 .trigger() 或辅助函数，例如

$('#waterloo').mouseover() // will fire a 'mouseover' event

或

$('#waterloo').trigger('mouseover');

Answer 3

这可能就是您正在寻找的。

http://www.infinitywebcreations.com/2011/01/how-to-create-a-throbbingpulsing-image-effect-with-jquery/" infinitywebcreations.com/2011/01/how-to-create-a-throbbingpulsing-image-effect-with-jquery/

Answer 4

我个人会做这样的事情，当鼠标悬停在图像上时发出脉冲，并在鼠标移出时返回到完全不透明......

$(document).ready(function () {

    function Pulse(Target, State) {
        //Every 750ms, fade between half and full opacity
        $(Target).fadeTo(750, State?1:.5, function() {Pulse(Target, !State)});
    }

    $("#ImageId").hover(function () {
        $(this).stop()
        Pulse(this);
    }, function () {
        $(this).stop(false, true).fadeTo(200, 1); //200ms to return to full opacity on mouse out
    });
});