尝试编写 JavaScript 幻灯片,但一段时间后图像不对齐

Trying to write a javascript slideshow, but the images do not align after awhile

本文关键字:一段时间 图像 对齐 JavaScript 幻灯片      更新时间:2023-09-26

我正在构建这个网站,其中包含用javasript编写的图像幻灯片。这是相关的 html。

 <table>
    <tr>
      <td id="firstelement">
        <div id="leftsidebar"> 
          <img class="leftslide" src="/images/IMG_96768613163825.jpeg">
          <img class="leftslide" src="/images/IMG_96772192197469.jpeg">
          <img class="leftslide" src="/images/IMG_96781303842831.jpeg">
          <img class="leftslide" src="/images/IMG_96785091848819.jpeg">
          <img class="leftslide" src="/images/IMG_96764834500597.jpeg">
        </div>
      </td>
      <td id="secondelement">
        <div id="slideshow">
          <img class="slide" src="/images/IMG_96764834500597.jpeg">
          <img class="slide" src="/images/IMG_96768613163825.jpeg">
          <img class="slide" src="/images/IMG_96772192197469.jpeg">
          <img class="slide" src="/images/IMG_96781303842831.jpeg">
          <img class="slide" src="/images/IMG_96785091848819.jpeg">
        </div>
      </td>
      <td id="thirdelement">      
        <ul id="announcements"><h3>Announcements</h3>
          <li class="announcement">Announcement #1 - Dates and times could go here, along with a short description of the announcement.</li><hr>
          <li class="announcement">Announcement #2 - These could just be links to pages that have fliers or other representations of the announcements.</li><hr>
          <li class="announcement">Announcement #3 - Could even add images, experiment with fonts, etc.</li><hr>
          <li class="announcement">Announcement #4 - These would change as needed. I am only adding generic text because I am not aware of any current announcements that need posted.</li><hr>
         </ul>
       </td>       
   </tr>
 </table>  

这是幻灯片.js让它运行

// Global variables
var numslides = 0;
var numleftslides = 0;
var currentslide = 0, oldslide = 4;
var slide1 = 0;
var slide2 = 1;
var slide3 = 2;
var slide4 = 3;
var slide5 = 4;
var x = 0;
var a = 0;
var b = 240;
var c = 480;
var d = 720;
var e = 960;
var picWidth = 0;
var leftPicHeight = 0;
var slides = new Array();
var leftslides = new Array();
function makeSlideShow() {
  // hide the nav bar options
  setupMenu();
  // find all images with the class "slide"
  imgs = document.getElementsByTagName("img");
  for (i = 0; i < imgs.length; i++) {
    if (imgs[i].className != "slide" && imgs[i].className != "leftslide") continue;
    else if (imgs[i].className == "slide" ) {
      slides[numslides] = imgs[i];
      jQuery("#slideshow").css('width', jQuery(slides[numslides]).css('width'));
      // stack images with first slide on top
      if (numslides == 0) {
        imgs[i].style.zIndex = 10;
      }
      else {
        imgs[i].style.zIndex = 0;
      }
      //imgs[i].onclick = nextSlide;
      numslides++;
    }
    else {
      leftslides[numleftslides] = imgs[i];   
      numleftslides++;
    }
  } // end for loop
  nextSlide();
} // end makeSlideShow()
function nextSlide() {
  // Set current slide to be under the new top slide
  slides[currentslide].style.zIndex = 9;
  // Move older slide to the bottom of the stack
  slides[oldslide].style.zIndex = 0;
  oldslide = currentslide;
  currentslide++;
  if (currentslide >= numslides) currentslide = 0;
  // start at the right edge
  picWidth = parseInt(jQuery(slides[currentslide]).css('width'));
  jQuery(slides[currentslide]).css('left', -picWidth + "px");
  x = -picWidth;
  // Move the new slide to the top
  slides[currentslide].style.zIndex = 10;
  if (a < 0) a = 960;
  if (b < 0) b = 960;
  if (c < 0) c = 960;
  if (d < 0) d = 960;
  if (e < 0) e = 960;
  animateSlide();
  window.setTimeout("nextSlide();", 5000); 
}
function animateSlide() {
  // Lower moves slower, higher moves faster
  x = Math.min(0, x + 7);
  a = Math.max(-240, a - 2);
  b = Math.max(-240, b - 2);
  c = Math.max(-240, c - 2);
  d = Math.max(-240, d - 2);
  e = Math.max(-240, e - 2);
  // previous image moves off the left edge
  // (comment the next line for a different effect)
  jQuery(slides[oldslide]).css('left', (x + picWidth) + "px");
  jQuery(slides[currentslide]).css('left', x + "px");
  jQuery(leftslides[slide1]).css('top', a + "px");
  jQuery(leftslides[slide2]).css('top', b + "px");
  jQuery(leftslides[slide3]).css('top', c + "px");
  jQuery(leftslides[slide4]).css('top', d + "px");
  jQuery(leftslides[slide5]).css('top', e + "px");
  // repeat until slide is at zero position
  if (x < 0) window.setTimeout("animateSlide();", 1);
}
// create the slideshow when the page loads
jQuery(document).ready(makeSlideShow);

幻灯片实际上(有点(有效。在火狐和铬中,当浏览器启动时,它似乎工作正常。但是,当我将其最小化,然后再次将其调回时,图片仍然动画,但它们会错位。在Internet Explorer中,图像移动速度不够快,时间完全关闭。任何帮助将不胜感激。我将在网络竞赛中进入这个网站,明天下午我将对其进行演示。提前谢谢。

不是答案,但这太长了,无法发表评论:
有一些事情你可以优化。例如,无需按标签名称获取所有图像,然后使用 for 循环检查每个图像是否具有类名slide 然后将其添加到数组中。由于您已经在使用 jQuery,因此您可以获取所有幻灯片图像使用

var slides = jQuery.makeArray($(".slide"));

我刚刚将您的标记添加到 Fiddle 中(没有您的脚本(,并添加了一些虚拟图像和控制台日志消息,以便轻松检查此数组包含的内容。

供参考:http://api.jquery.com/jquery.makearray/

经过许多辛苦,我相信我知道问题是什么,我找到了解决它的方法。我相信可能正在发生的事情是,更改页面焦点打开和关闭会干扰幻灯片放映,以至于图像定位的计算跟不上显示。当你这样做时,这几乎就像你进入了"竞争条件"。因此,我通过具有window.onfocus(...)事件的适当函数触发器来重置所有内容。这允许在用户离开页面并返回时重置所有内容,例如在最小化和还原页面的情况下。由于IE加载图像的速度不够快,我放置了一个if-statement以查看浏览器是否是IE,然后以不同的方式处理事情。这似乎是一个很好的补丁。不幸的是,现在我意识到真正的大屏幕会扭曲网站并干扰某些功能。我想我现在只能接受这一点,但如果有人对此有任何建议,我会全力以赴。感谢所有参与这个问题的人。