JQuery spinner type thing

Question

I am trying to create an object of type spinner like jQuery earlier, today someone gave me this code, which increases the value of the text field up / down when the button is clicked. Fantasy. But what do you do to disable the .desc button, if the value is 0 - zero. In PHP it is very easy, if if <= 0, then this, etc., but I don’t know jQuery ..

Also any ideas on how it can be used to move up / down the html unordered list, i.e. ul li?

$(document).ready(function() 
{   
    $(function()
    {
        $(".inc").click(function() 
        { 
            $(":text[name='qty']").val(Number($(":text[name='qty']").val()) + 1);
        }); 

        $(".dec").click(function()
        {      
            $(":text[name='qty']").val(Number($(":text[name='qty']").val()) - 1);
        });  
    });
});

The form is used here:

<input type="text" name="qty" value="0" />
<img src="img/up.png" class="inc" width="20px" height="9px" alt="Increase" title="increase" />
<img src="img/down.png" class="dec" width="20px" height="9px" alt="Decrease" title="Decrease" />

Answer 1

here is my code

$(document).ready(function () {
  var textElem = $(":text[name='qty']"),
      getTextVal = function() {
        var val = parseInt(textElem.val(), 10);
        return isNaN(val) ? 0 : val;
      };

  $(".inc").click(function () {
      textElem.val(getTextVal() + 1);
  });

  $(".dec").click(function(){
      if( getTextVal() == 0) {
         return false;
      }

      textElem.val(getTextVal() - 1);
  });
});

".dec" , 0, () , .

, css .

, , .

Answer 2

uhm jQuery javascript,

$(".dec")
    .click(
        function(){
            if(Number($(":text[name='qty']").val() > 0)
            {
                $(":text[name='qty']")
                    .val( Number($(":text[name='qty']").val()) - 1 
                );
            }
         }
     );

, javascript if.

Answer 3

, - . :

$(":text[name='qty']").change(function() {
    if($(this).val() <= 0) {
        $(".dec").hide();
    } else {
        $(".dec").show();
    }
}):

"button" , :

    if($(this).val() <= 0) {
        $(".dec").attr('disabled','disabled');
    } else {
        $(".dec").removeAttr('disabled');
    }

Answer 4

. , spinner , .hide() .show() increment decrement.

function increment() {
    var textField = $(":text[name='qty']");
    var value = Number(textField.val()) + 1;
    textField.val(value);
}

function decrement() {
    var textField = $(":text[name='qty']");
    var value = Number(textField.val()) - 1;
    textField.val(value);
    if(value == 0) {
        $(".dec").attr("disable", "disable");
    }
}

$(document).ready(function() {
    $(".inc").click(increment);
    $(".dec").click(decrement);
});

, . decrement , 0. , . - :

if(current == $("#list > li").size() - 1) {
    $(".inc").attr("disable", "disable");
}

, , . , .