0

我有以下代码，我已经“拼凑”在一起。基本上它应该需要一些 JSON 数据（下面也是一个示例），预加载任何适用的图像并修改幻灯片以使用传回的数据。

它正在工作，但是图像和文本不匹配，我认为这与它有关，currImg++%preloadArrayName.length但我不确定这意味着什么......

任何帮助感激不尽！

function updateHomepageSlideshow(data)
{
var preloadArr = new Array();
var preloadArrName = new Array();
var preloadArrOffer = new Array();
var i;

/* preload images */
for(i=0; i < data.length; i++){
    preloadArr[i] = new Image();
    preloadArr[i].src = 'http://media.domain.com/restaurants/large/' + data[i]   ['restaurantCode'] + '.jpg';
    preloadArrName[i] = data[i]['restaurantName'];
    preloadArrOffer[i] = data[i]['offerName'];
}

var currImg = 1;
var intID = setInterval(changeImg(data), 6000);

/* image rotator */
function changeImg(data){
    $('#amazingOffersAt').hide();
    $('#homepageRestaurantNameId').html(preloadArrName[currImg++%preloadArrName.length]);
    $('#homepageRotatingImage').css('background-image','url(' + preloadArr[currImg++%preloadArr.length].src +')');
    $('#homepageRestaurantOfferId').html(preloadArrOffer[currImg++%preloadArrOffer.length]);
}
}

JSON

[{
"restaurantName": "Caf\u00e9 des Amis",
"restaurantCode": "cafe-des-amis",
"address": "11 - 14 Hanover Place",
"town": "Covent Garden",
"county": "London",
"postcode": "WC2E 9JP",
"lat": "51.5133900",
"lng": "-0.1231300",
"largeImage": "1",
"offerTypeId": "9",
"offerName": "3 course set menu for \u00a315"
}, {
"restaurantName": "Palm Court Brasserie",
"restaurantCode": "palm-court-brasserie",
"address": "39 King Street",
"town": "Covent Garden",
"county": "London",
"postcode": "WC2E 8JS",
"lat": "51.5119700",
"lng": "-0.1243000",
"largeImage": "1",
"offerTypeId": "12",
"offerName": "3 courses and a kir royale \u00a322.50"
}, {
"restaurantName": "Clos Maggiore",
"restaurantCode": "clos-maggiore",
"address": "33 King Street",
"town": "Covent Garden",
"county": "London",
"postcode": "WC2E 8JD",
"lat": "51.5116900",
"lng": "-0.1247700",
"largeImage": "1",
"offerTypeId": "12",
"offerName": "2 courses: \u00a315.50"
}, {
"restaurantName": "Navajo Joe",
"restaurantCode": "navajo-joe",
"address": "34 King Street",
"town": "Covent Garden",
"county": "London",
"postcode": "WC2E 8JD",
"lat": "51.5116900",
"lng": "-0.1247700",
"largeImage": "1",
"offerTypeId": "1",
"offerName": "50% Off Your Food "
}, {
"restaurantName": "Le Deuxieme",
"restaurantCode": "le-deuxieme",
"address": "65a Long Acre, Covent Garden",
"town": "London",
"county": "West End London",
"postcode": "WC2E 9JD",
"lat": "51.5139100",
"lng": "-0.1227800",
"largeImage": "1",
"offerTypeId": "12",
"offerName": "Sunday offer: 3 courses &amp; half bottle of wine \u00a320"
}]
4

2 回答 2

2

你应该使用

var currImg = 0; // let's start at first image
var intID = setInterval(changeImg, 6000); // you don't need the data and you were passing the result of the function, not the function
/* image rotator */
function changeImg(data){
    $('#amazingOffersAt').hide();
    var index = currImg++%preloadArrName.length;
    $('#homepageRestaurantNameId').html(preloadArrName[index]);
    $('#homepageRotatingImage').css('background-image','url(' + preloadArr[index].src +')');
    $('#homepageRestaurantOfferId').html(preloadArrOffer[index]);
}

currImg++您的代码没有在每一行使用与increments相同的索引currImg。

更准确地说，currImg++%preloadArrayName.length是(currImg++)%preloadArrayName.length（参见优先级）：它采用模数currImg来确保获得一个值[0, preloadArrayName.length[（即数组中的有效索引）并递增currImg。

请注意，您的代码仅在 3 个数组具有相同大小时才有效。我不会使用 3 个数组，而是只使用一个数组但包含对象（就像你在 json 中拥有的那样）。

于 2012-11-26T18:22:00.783 回答
0

你确定你在 changeImg() 中用来增加索引的方法吗？进行模数运算有什么意义？也许我错过了一些东西。

如果您想简单地遍历图像，为什么不这样做：

var currImg = 0;

function changeImg(data){

if(currImg == preloadArrName.length - 1){
   currImg = 0; // reset index to the first element
}else{
   currImg++ // increment the index to the next element
}
$('#amazingOffersAt').hide();

$('#homepageRestaurantNameId').html(preloadArrName[index]);
$('#homepageRotatingImage').css('background-image','url(' + preloadArr[index].src +')');
$('#homepageRestaurantOfferId').html(preloadArrOffer[index]);

}

于 2012-11-26T19:47:48.667 回答