Cycle Through Divs

Question

I need to cycle through some divs using jQuery. What I mean by cycle is that I have a series of 7 divs:

Sample text
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Answer 1

We need to iterate a set and handle its visibility properties.

First of all, let me show you two libraries I have created. The first is Iterable, which is designed to handle all kinds of iterations:

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]);
    }

}

The second is Visiblary, which is designed to handle all kinds of visibility events:

/*
 * 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;
}

And, assuming that one uses these tools and the seven elements are already created, this is the script which solves the issue:

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);