javascript - 下拉选择时如何更改div背景颜色？

Question

当页面加载语言和排名时将列出。我的目的是在选择下拉菜单时更改语言 div 颜色。如果我选择排名 5 完全填充语言 div 的颜色。我很困惑，我不知道如何为每个 div 随机生成颜色。

我附上了一张图片。

请查看

Demo

JS

//fake data for this test
var response = {
    availableLanguage: [{
        id: "1",
        language_id: "English",
        title_en: "USEnglish"
    }, {
        id: "2",
        title_en: "Hindi"
    }, {
        id: "3",
        title_en: "Arabi"
    }

    ]
}


var responseDB = {
    selectLanguageRankingTagId: [{
        id: "1",
        user_id: "11",
        language_id: "English",
        ranking: "2",
        title_en: "English"
    }, {
        id: "2",
        user_id: "11",
        language_id: "German",
        ranking: "3",
        title_en: "German"
    }, {
        id: "3",
        user_id: "11",
        language_id: "French",
        ranking: "4",
        title_en: "French"
    }

    ]
}


var $languagemodal = $('#languagemodal'); // get the modal and the dialog div
var $dialog = $languagemodal.find('.modal-dialog');

//$languagemodal.modal({show: true}); // just to show the modal for the demo

// get languages
//$.get("/tag/language", function(response){
        var optionLang = '';
        for (var i = 0; i < response.availableLanguage.length; i++) {
            engLangID  = response.availableLanguage[i].id;
            engLang    = response.availableLanguage[i].title_en;
            optionLang += '<option value="'+engLangID+'" data-language="'+engLang+'">'+engLang+'</option>';
        }

// load the modal content div
$dialog.html('<div class="modal-content"><div class="modal-header "><button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button><h4 class="modal-title">Edit Languages</h4></div><div class="modal-body"><div class="appendRow"></div></div><div class="modal-footer"><div class="row"><select class="form-control input-sm addMore"><option selected="selected">Add Language</option>' + optionLang + '</select></div><br><button type="button" class="btn btn-default" data-dismiss="modal">Close</button><button type="button" class="btn btn-primary">Save changes</button></div></div>');

// get the modal body we just added
var $modalBody = $dialog.find('.modal-body');

// loop over your data, you would have this in your $.get function 
$.each(responseDB.selectLanguageRankingTagId, function (i, item) {
    delID = item.id;
    // make the row
    var $newRow = $('<div class="row"><div class="col-md-8"><h4 style="background-color: lightgrey; border-radius: 10px; background-repeat: repeat; height: 30px; margin:5px 0px; padding:4px 5px;">' + item.title_en + '</h4></div><div class="col-md-3" style="padding:5px;"><select class="form-control input-sm" id="' + item.id + '" data-item="' + item + '"><option value="1">1</option><option value="2">2</option><option value="3">3</option><option value="4">4</option><option value="5">5</option></select><span class="glyphicon glyphicon-remove removefetchedData" data-removefile="" data-id="'+item.id+'" ></span></div></div>')
    // set the select value
    $newRow.find('select').val(item.ranking);
    // add the row to the modal body
    $modalBody.append($newRow);

});

//remove rank and language of users
                $( ".removefetchedData" ).click(function(e){
                    e.preventDefault();
                    alert($(this).data('id'));
                    /*$.post("/language/delete", {rateUserLangID: userLangDelID}, function(html){
                     //append css design
                     });*/
                });

$(".modal-dialog").on('change', ".addMore", function(){
            var selected = $( this ).find(':selected');
            language       = selected.data('language');
            languageID     = selected.val();
            $( ".appendRow" ).append('<div class="row"><div class="col-md-8"><h4 style="background-color: lightgrey; border-radius: 10px; background-repeat: repeat; height: 30px; margin:5px 0px; padding:4px 5px;">'+language+'</h4></div><div class="col-md-3" style="padding:5px;"><select class="form-control input-sm"><option value="1">1</option><option value="2">2</option><option value="3">3</option><option value="4">4</option><option value="5">5</option></select><span class="glyphicon glyphicon-remove removefile" data-removefile=""></span></div></div>');
        });    

$('.modal-dialog').on('click', '.removefile', function() {
    $(this).closest('.row').remove();
});

 //});// get languages end  

HTML

<div id="languagemodal">
  <div class="modal-dialog" style="margin: 54px 0px;"></div>
</div>

Answer 1

在脚本端使用代码块

$('.form-control').change(function(e){
  var colors=['red','blue','yellow','brown','green']; 
  $(e.target.parentNode).parent('div.row').find('h4').css({"background-color":colors[e.target.selectedIndex],"width" :(parseInt(e.target.options[e.target.selectedIndex].value) * 20) +"%"});
});

http://jsfiddle.net/Lr6a5d2v/23/