Next/Previous buttons for Radio

Question

I'm trying to add "Next" & "Previous" buttons to a radio style navigation.

HTML

<div class="month-picker"> 
    <button type="buton" class="month-picker-nav" onclick="dayNavigation('prev');">&lt;</button> 
    <fieldset class="month-picker-fieldset">
        <input type="radio" name="month" value="day1" id="day1" checked="checked">
        <label for="day1" class="month-picker-label">Day 1</label>
        <input type="radio" name="month" value="day2" id="day2">
        <label for="day2" class="month-picker-label">Day 2</label>
        <input type="radio" name="month" value="day3" id="day3">
        <label for="day3" class="month-picker-label">Day 3</label>
        <input type="radio" name="month" value="day4" id="day4">
        <label for="day4" class="month-picker-label">Day 4</label>
        <input type="radio" name="month" value="day5" id="day5">
        <label for="day5" class="month-picker-label">Day 5</label>
        <input type="radio" name="month" value="day6" id="day6">
        <label for="day6" class="month-picker-label">Day 6</label>
        </fieldset> 
        <button type="buton" class="month-picker-nav" onclick="dayNavigation('next');">&gt;</button>
</div>

JAVASCRIPT:

dayNavigation = function (direction) {
    var all = $('.month-picker-fieldset input:radio');
    var current = $('.month-picker-fieldset input:radio:checked');
    var index;
    if (direction == 'prev') {
        index = all.index(current) - 1;       
    } else {
        index = all.index(current) + 1;        
    }    
    all.eq(index).attr('checked', 'checked');
    return false;
};

Fiddle: http://jsfiddle.net/hTgv3/5/

My problem is that the previous button doesn't work, and once the selection or "click" has been invoked manually, the next button no longer works.

Answer 1

You should use a click instead of setAttribute to perform the proper action:

all.eq(index).click();

Also, you need to check if the index is greater or equal to the max list size. If it is, loop back to first element (0):

if(index >= all.size()) index = 0;

http://jsfiddle.net/samliew/hTgv3/11/