Question

I have a little problem and i don’t really how to fix it,
If I have all the checkboxes selected it will appear “deselect all” but if i deselect one or two i want my “select all” appear again, my issue is that if I select every checkbox and i start manually unchecking one by one it suppose to activate select all again, but if I press select all it will uncheck everything instead of check all.

This is part of my HTML code:

<input type="button" class="btn-primary btn-mini" id="check1" value="Check All" /> 
<input type="hidden" id="isChkd" value="true" />                                                                      
<input type="checkbox" name="" value="" class="cb1-element"> 751        
<input type="checkbox" name="" value="" class="cb1-element"> 752                                                                  
<input type="checkbox" name="" value="" class="cb1-element"> 753                                                                  
<input type="checkbox" name="" value="" class="cb1-element"> 754                                                                  

My JS:

$('#check1').toggle(function(){
    $('.cb1-element').attr('checked','checked');
    $(this).val('Uncheck All');
    $('#isChkd').val(true);
},function(){
    $('.cb1-element').removeAttr('checked');
    $(this).val('Check All');     
    $('#isChkd').val(false);
})

$('.cb1-element').change(function(){
    if($('#isChkd').val() == false){
        $('#check1').val('Uncheck All');
        $('#isChkd').val(true);
    }else{
        $('#check1').val('Check All');
        $('#isChkd').val(false);
    }
});

Answer 1

$('#check1').click(function(){
    if($('#isChkd').val() == 'true'){
        $('.cb1-element').attr('checked','checked');
        $(this).val('Uncheck All');
        $('#isChkd').val('false');
    }
    else{
        $('.cb1-element').removeAttr('checked');
        $(this).val('Check All');     
        $('#isChkd').val('true');
    }
});

$('.cb1-element').change(function(){
    var all = $('input.cb1-element').length;
    var checked = $('input.cb1-element:checked').length;
    if(all == checked){
        $('#check1').val('Uncheck All');
        $('#isChkd').val('false');
    }else{
        $('#check1').val('Check All');
        $('#isChkd').val('true');
    }
});

working jsFiddle here http://jsfiddle.net/C9Tw2/18/