twitter-bootstrap - knockout Twitter Bootstrap 弹出框绑定(bind)

Question

我正在尝试为引用模板的 twitter boostrap 弹出框创建自定义绑定(bind)，但是一旦创建弹出框内的内容的绑定(bind)部分，我遇到了问题。

我以前看过这个问题，但我觉得它们大多都很困惑，而且我非常接近一个可重用的解决方案，它可以按照我的意愿使用模板。

http://jsfiddle.net/billpull/Edptd/

// Bind Twitter Popover
ko.bindingHandlers.popover = {
    init: function(element, valueAccessor, allBindingsAccessor, viewModel, bindingContext) {
        var tmplId = ko.utils.unwrapObservable(valueAccessor());
        var tmplHtml = $('#' + tmplId).html();
        var uuid = guid();
        var domId = "ko-bs-popover-" + uuid;
        var tmplDom = $('<div/>', {
            "class" : "ko-popover",
            "id" : domId
        }).html(tmplHtml);

        options = {
            content: tmplDom[0].outerHTML
        };

        var popoverOptions = ko.utils.extend(ko.bindingHandlers.popover.options, options);

        console.log($(element));
        console.log(element);

        $(element).bind('click', function () {
            $(this).popover(popoverOptions).popover('toggle');
            ko.applyBindings(bindingContext, document.getElementById(domId));
        });
    },
    options: {
        placement: "right",
        title: "",
        html: true,
        content: "",
        trigger: "manual"
    }
};

===编辑

根据下面的答案更新了代码，允许您在没有额外的 withProperties 绑定(bind)的情况下执行此操作

// Bind Twitter Popover
ko.bindingHandlers.popover = {
    init: function(element, valueAccessor, allBindingsAccessor, viewModel, bindingContext) {
        // read popover options 
        var popoverBindingValues = ko.utils.unwrapObservable(valueAccessor());

        // set popover template id
        var tmplId = popoverBindingValues.template;

        // set popover trigger
        var trigger = popoverBindingValues.trigger;

        // get template html
        var tmplHtml = $('#' + tmplId).html();

        // create unique identifier to bind to
        var uuid = guid();
        var domId = "ko-bs-popover-" + uuid;

        // create correct binding context
        var childBindingContext = bindingContext.createChildContext(viewModel);

        // create DOM object to use for popover content
        var tmplDom = $('<div/>', {
            "class" : "ko-popover",
            "id" : domId
        }).html(tmplHtml);

        // set content options
        options = {
            content: tmplDom[0].outerHTML
        };

        // Need to copy this, otherwise all the popups end up with the value of the last item
        var popoverOptions = $.extend({}, ko.bindingHandlers.popover.options);
        popoverOptions.content = options.content;

        // bind popover to element click
        $(element).bind(trigger, function () {
            $(this).popover(popoverOptions).popover('toggle');

            // if the popover is visible bind the view model to our dom ID
            if($('#' + domId).is(':visible')){
                ko.applyBindingsToDescendants(childBindingContext, $('#' + domId)[0]);
            }
        });

        return { controlsDescendantBindings: true };
    },
    options: {
        placement: "right",
        title: "",
        html: true,
        content: "",
        trigger: "manual"
    }
};

Answer 1

您需要使用我的老 friend ，custom bindings .

ko.bindingHandlers.withProperties = {
    init: function(element, valueAccessor, allBindingsAccessor, viewModel, bindingContext) {
        // Make a modified binding context, with a extra properties, and apply it to descendant elements
        var newProperties = valueAccessor(),
            innerBindingContext = bindingContext.extend(newProperties);
        ko.applyBindingsToDescendants(innerBindingContext, element);

        // Also tell KO *not* to bind the descendants itself, otherwise they will be bound twice
        return { controlsDescendantBindings: true };
    }
};

然后，您需要在生成的 html 中添加一个 data-bind 属性:

    var tmplDom = $('<div/>', {
        "class": "ko-popover",
        "id": domId,
        "data-bind": "withProperties: { label: '" + viewModel.label() + "', required: '" + viewModel.required() + "' }"

我整理了一个 jsFiddle显示这一点。有几个陷阱，我必须为每个弹出框复制弹出框选项，否则它们都会以最后一组值结束。

    var popoverOptions = $.extend({}, ko.bindingHandlers.popover.options);
    popoverOptions.content = options.content;

而且我还必须仅在弹出窗口可见时才对弹出窗口应用绑定(bind)，否则它似乎试图绑定(bind)到整个页面。

$(element).bind('click', function () {
            $(this).popover(popoverOptions).popover('toggle');
            // If you apply this when the popup isn't visible, I think that it tries to bind to thewhole pageand throws an error
            if($('#' + domId).is(':visible'))
            {
                ko.applyBindings(viewModel, $('#' + domId)[0]);
            }
        });

这似乎也是双向的，因为您可以更改弹出窗口中的值并更新非弹出元素，但我不会撒谎，我没想到会发生这种情况!