淘汰自定义绑定光滑js无法正常工作

时间:2015-11-13 05:13:21

标签: javascript knockout.js slick.js ko-custom-binding

我没有敲除绑定的工作代码是:

<div class="slick_demo_1">

                    <div>
                        <div class="ibox-content">
                            <h2>Slide 1</h2>
                        </div>
                    </div>
                    <div>
                        <div class="ibox-content">
                            <h2>Slide 2</h2>
                        </div>
                    </div>
                    <div>
                        <div class="ibox-content">
                            <h2>Slide 3</h2>
                        </div>
                    </div>
                </div>

初始化光滑我的js代码是:

$('.slick_demo_1').slick({
                dots: true
            });

上面的代码工作正常。 现在敲除绑定的代码是:

<div class="slick_demo_1" data-bind="foreach:showSlider">

                    <div>
                        <div class="ibox-content">
                            <h2 data-bind="slider"></h2>
                        </div>
                    </div>
                </div>

为了用DOM绑定光滑,我的代码是:

ko.bindingHandlers.slick = { 
            init: function (element, valueAccessor) {
                $(element).slick({
                    dots: true
                });
            }
        };

但是自定义绑定无效。我做错了什么?

1 个答案:

答案 0 :(得分:4)

您展示的代码几乎不像自定义活页夹的正确实现。

一些提示:

  • 您应该在根元素中使用自定义绑定
  • 自定义绑定应该负责构建,如果可能的话,从元素中删除轮播API(使用光滑的destroyunslick)如果元素被ko处理
  • 自定义活页夹应该能够更新轮播内的元素
  • 使用额外的slickOptions绑定将其他对象传递给光滑初始化会很有趣

自定义绑定is explained here的基本结构。请参阅代码模板:

ko.bindingHandlers.yourBindingName = {
init: function(element, valueAccessor, allBindings, viewModel, bindingContext) {
    // This will be called when the binding is first applied to an element
    // Set up any initial state, event handlers, etc. here
},
update: function(element, valueAccessor, allBindings, viewModel, bindingContext) {
    // This will be called once when the binding is first applied to an element,
    // and again whenever any observables/computeds that are accessed change
    // Update the DOM element based on the supplied values here.
}

};

如上所述,init负责初始化caroulse,update负责在阵列更改时更新轮播的内容。 R P Niemeyer在这里对自定义绑定进行了深入的解释:Another Look at Custom Bindings for KnockoutJS

如果您正确实现它,您的HTML代码应如下所示:

<div data-bind="slick: imagesArray, slickOptions: additionalOptions>
</div>

init上,您的自定义绑定应根据imagesArray创建元素,并使用additionalOptions(如果存在)调用光滑初始化,并在元素由ko处理。在更新中,您应该修改内部元素并可能重新应用光滑。您还应该查看slick's API

This fiddle显示了部分实现,但更完整的是当前的floowing片段:

var imageUrls = [];
var i = 1;
for (i=1;i<=10;i++)
    imageUrls.push('http://lorempixel.com/400/200/animals/'+i);

ko.bindingHandlers.slick = {
    init: function(element, valueAccessor, allBindingsAccessor) {
        // Clears the div
        $(element).empty();
        // Creates the inner divs with images
        var images = ko.unwrap(valueAccessor());
        if (images) {
        	images.forEach(function(imgUrl) {
                $div = $('<div>');
                $image = $('<img>');
                $image.attr('src',imgUrl);
                $div.append($image);
                $(element).append($div)
            });
        }

        // try to recover slickOptions
        var options = allBindingsAccessor().slickOptions || {};

        // Initialize slick on the div, with provided options
        $(element).slick(options);

        //handle disposal, if KO removes the element
        ko.utils.domNodeDisposal.addDisposeCallback(element, function() {
            $(element).slick('unslick');
        });
    },
    //update the control when the view model changes
    update: function(element, valueAccessor) {
        var images = ko.unwrap(valueAccessor());
        // Do something to update the content
    }
};


var vm = {
    images: ko.observableArray(imageUrls),
    options: {}
}

ko.applyBindings(vm, gallery);
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.2.0/knockout-min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
<script src="https://cdn.jsdelivr.net/jquery.slick/1.5.8/slick.min.js"></script>
<link href="https://cdn.jsdelivr.net/jquery.slick/1.5.8/slick.css" rel="stylesheet">
<link href="https://cdn.jsdelivr.net/jquery.slick/1.5.8/slick-theme.css" rel="stylesheet">

<div id="gallery" 
     style="width:400px"
     data-bind="slick: images, slickOptions: {dots:true, initialSlide:4}">
</div>

如果imgUrls发生变化,实现中缺少的部分就是更新库。但它显示了提示中的主要技巧。