循环遍历 Div

Question

我需要使用 jQuery 循环浏览一些 div。我所说的循环是指我有一系列 7 个 div：

<div id="content-1">Sample text</div>
<div id="content-2">Sample text</div>
<div id="content-3">Sample text</div>
<div id="content-4">Sample text</div>
<div id="content-5">Sample text</div>
<div id="content-6">Sample text</div>
<div id="content-7">Sample text</div>

我需要发生的是每 5 秒我需要它们改变一次。因此，div“Content-1”将显示 5 秒，然后 div“Content 2”将显示 5 秒，依此类推。

我觉得这很容易做到，但当涉及到 JavaScript 和 jQuery 时，我是个白痴。

Answer 1

var divs = $('div[id^="content-"]').hide(),
    i = 0;

(function cycle() { 
    divs.eq(i).fadeIn(400)
              .delay(5000)
              .fadeOut(400, cycle);

    i = ++i % divs.length; // increment i, 
                           //   and reset to 0 when it equals divs.length
})();

演示： （延迟较短） http://jsfiddle.net/eFjnU/

---

如果您不想要淡入淡出动画，请使用 show 和 hide。您仍然需要给出一个持续时间，以便延迟和回调能够正常工作。

var divs = $('div[id^="content-"]').hide(),
    i = 0;

(function cycle() { 

    divs.eq(i).show(0)
              .delay(1000)
              .hide(0, cycle);

    i = ++i % divs.length;

})();

演示： （延迟较短） http://jsfiddle.net/eFjnU/1/

Answer 2

简单的 jQuery 淡入淡出画廊幻灯片，

悬停时暂停：

// FADESHOW // Simple fade gallery
$(".fadeShow").each(function() {

  var $slides = $(this).children(),
      tot = $slides.length,
      itv = null,
      idx = 0; 
      
  $slides.eq(idx).show();
  
  function anim() { $slides.fadeOut().eq(++idx % tot).fadeIn(); }
  function play() { itv = setInterval(anim, 2000); }
  function stop() { clearInterval(itv); }
  
  $(this).hover(stop, play);
  
  play();
  
});

body{margin:0;}

/* FADESHOW basic CSS */
.fadeShow {
  position:relative;
}
.fadeShow > * {
  position:absolute;
  display:none;
  height: inherit;
  width: 100%;
}

/* FADESHOW (your styles) */
.gal_1 { height:80px; }

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<div class="fadeShow gal_1">
  <div style="background:#0bf;">1 Hover to pause</div>
  <div style="background:#fb0;">2 You can have as many slideshows as you want</div>
  <div style="background:#b0f;">3</div>
</div>

<div class="fadeShow">
  <p>LOREM</p>
  <p>IPSUM</p>
  <p>DOLOR</p>
  <p>SOMETHING</p>
</div>

.fadeShow() jQuery 插件

如果您想将其转换为 simpls jQuery 插件 以允许不同的淡入淡出和暂停值并包含其他选项：

// FADESHOW // Simple fade gallery by Roko :)
(function($){
  $.fn.fadeShow = function(options) {

    var op = $.extend({
      pause : 3800,
      fade  : 600,
      pauseHover : true
    }, options);

    return this.each(function() {

      var $slides = $(this).children(),
          tot = $slides.length,
          itv = null,
          idx = 0; 

      $slides.eq(idx).show();

      function anim() { $slides.fadeOut(op.fade).eq(++idx % tot).fadeIn(op.fade); }
      function play() { itv = setInterval(anim, op.fade+op.pause); }
      function stop() { clearInterval(itv); }

      if(op.pauseHover) $(this).hover(stop, play);

      play();

    });
  };
}(jQuery));


// Basic example
$(".gal1").fadeShow();

// With options
$(".gal2").fadeShow({
  pause : 4000,
  fade : 1000,
  pauseHover : false
});

/* FADESHOW basic CSS */
.fadeShow {
  position:relative;
}
.fadeShow > * {
  position:absolute;
  display:none;
  height: inherit;
  width: 100%;
}

/* FADESHOW (your styles) */
.gal1 { height:80px; }

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<div class="fadeShow gal1">
  <div style="background:#0bf;">1 Hover to pause</div>
  <div style="background:#fb0;">2 You can have as many slideshows as you want</div>
  <div style="background:#b0f;">3</div>
</div>

<div class="fadeShow gal2">
  <p>pauseHover : false</p>
  <p>IPSUM</p>
  <p>DOLOR</p>
  <p>SOMETHING</p>
</div>

Answer 3

我们需要迭代一个集合并处理它的可见性属性。

首先，让我向您展示我创建的两个库。第一个是 Iterable，它被设计用来处理各种迭代：

function Iterable(params) {
    var prevHandlers = [];
    var nextHandlers = [];
    var that = this;
    this.current = params.current;

    function ensureArray() {
        if (!that.elements) {
            that.elements = [];
        } else if (!Array.isArray(that.elements)) {
            that.elements = $.map(that.elements, function(value, index) {
                return [value];
            });
        }
        return that.elements;
    }

    function calculateCount() {
        that.count = ensureArray().length;
    }

    this.setElements = function(elements) {
        this.elements = elements;
        calculateCount();
    };

    this.prev = function(amount) {
        if (amount === undefined) {
            amount = 1;
        }
        //Modulo twice to make sure current will be positive
        that.current = (((that.current - amount) % that.count) + that.count) % that.count;
        while (amount--) {
            for (var prevHandler in prevHandlers) {
                prevHandlers[prevHandler](params);
            }
        }
    };

    this.next = function(amount) {
        if (amount === undefined) {
            amount = 1;
        }
        that.current = (that.current + amount) % that.count;
        while (amount--) {
            for (var nextHandler in nextHandlers) {
                nextHandlers[nextHandler](params);
            }
        }
    };

    this.getCurrent = function() {
        return that.elements[that.current];
    };

    this.setCurrent = function(current) {
        for (var index in that.elements) {
            if (that.elements[index] === current) {
                that.current = index;
                return true;
            }
        }
        return false;
    };

    this.pushElement = function(element) {
        that.elements.push(element);
    };

    this.pushElements = function(elements) {
        for (var element in elements) {
            that.pushElement(elements[element]);
        }
    };

    this.insertElement = function(element, index) {
        that.elements.splice(index, 0, element);
    };

    this.insertElements = function(elements, indexes, leftToRight) {
        var start = 0;
        var end = indexes.length - 1;
        if (leftToRight === false) {
            var aux = start;
            start = end;
            end = aux;
        }
        var leap = (start < end) ? 1 : -1;
        while (start - leap !== end) {
            that.insertElement[elements[indexes[start]]];
            start += leap;
        }
    };

    this.popElement = function() {
        that.elements.pop();
    };

    this.popElements = function(amount) {
        that.elements.splice(that.elements.length - amount, amount);
    };

    this.removeElement = function(index) {
        that.elements.splice(index, 1);
    };

    this.removeElements = function(indexes, leftToRight) {
        var start = 0;
        var end = indexes.length - 1;
        if (leftToRight === false) {
            var aux = start;
            start = end;
            end = aux;
        }
        var leap = (start < end) ? 1 : -1;
        while (start - leap !== end) {
            that.removeElement(indexes[start]);
            start += leap;
        }
    };

    this.register = {
        prev: function(param) {
            if (Array.isArray(param)) {
                for (var func in param) {
                    prevHandlers.push(param[func]);
                }
            } else {
                prevHandlers.push(param);
            }
        }, 
        next: function(param) {
            if (Array.isArray(param)) {
                for (var func in param) {
                    nextHandlers.push(param[func]);
                }
            } else {
                nextHandlers.push(param);
            }
        }
    };

    this.setElements(params.elements);
    if ((!!this.current) && (!Array.isArray(params.elements))) {
        this.setCurrent(params.elements[params.current]);
    }

}

第二个是 Visiblary，它被设计用来处理各种可见性事件：

/*
 * params:
 *     - selector: jQuery selector
 *     - init: function which gets the Visiblary object to initialize it
 *     - events: object/array
 *         - root: a selector which contain all the affected tags, default is "body"
 *         - types: array, which contains the string representation of the events
 *         - selector: inner selector to identify the target set
 *         - handler: handler function
 */
function Visiblary(params) {
    var instance = this;
    if (!params.toggleClass) {
        params.toggleClass = "invisible";
    }
    this.hideAll = function() {
        $(params.selector).addClass(params.toggleClass);
        return instance;
    };
    this.hideSubset = function(subsetSelector) {
        $(params.selector).filter(subsetSelector).addClass(params.toggleClass);
        return instance;
    };
    this.hideOnly = function(subsetSelector) {
        $(params.selector).not(subsetSelector).removeClass(params.toggleClass);
        $(params.selector).filter(subsetSelector).addClass(params.toggleClass);
        return instance;
    };
    this.showAll = function() {
        $(params.selector).removeClass(params.toggleClass);
        return instance;
    };
    this.showSubset = function(subsetSelector) {
        $(params.selector).filter(subsetSelector).removeClass(params.toggleClass);
        return instance;
    };
    this.showOnly = function(subsetSelector) {
        $(params.selector).not(subsetSelector).addClass(params.toggleClass);
        $(params.selector).filter(subsetSelector).removeClass(params.toggleClass);
        return instance;
    };
    this.invert = function() {
        $(params.selector).each(function() {
            $(this).hasClass(params.toggleClass) ? $(this).removeClass(params.toggleClass) : $(this).addClass(params.toggleClass);
        });
        return instance;
    };
    if (!!params.init) {
        params.init(this);
    }
    if (!!params.events) {
        for (var event in params.events) {
            $(!!params.events[event].root ? params.events[event].root : "body").on(params.events[event].types.join(" "), params.events[event].selector, params.events[event].handler);
        }
    }
    return instance;
}

并且，假设一个使用这些工具并且已经创建了七个元素，这是解决问题的脚本：

var myVisiblary = new Visiblary({
    selector: "#content-1, #content-2, #content-3, #content-4, #content-5, #content-6, #content-7"
});
myVisiblary.showOnly("#content-1");
var myIterable = new Iterable({
    elements: $("#content-1, #content-2, #content-3, #content-4, #content-5, #content-6, #content-7"),
    current: 0
});
myIterable.register.next(function() {myVisiblary.showOnly($(myIterable.getCurrent()))});
setInterval(function(){ myIterable.next(); }, 5000);