javascript - KnockoutJS 可观察值不是由 select 设置的

Question

我目前正在使用 knockoutJS + Durandal 和 JEE 后端开发一个 Web 应用程序，但我的问题是，当我更改选择时，我感觉我的可观察值尚未设置...

所以我为index.html选择了这个

    <label for="language" class="col-xs-12 col-sm-3 control-label no-padding-left no-padding-right"></span>
        Language selection:</label>
    <div class="col-sm-9">
        <select id="language"
                data-bind="options: possibleLanguage, optionsText: 'text', optionsValue: 'key', value: selectedLanguage"
                class="col-xs-12 col-sm-5"/>
        <span class="text-muted hidden-xs col-sm-12 no-padding-left">Select the language used to display the interaction.</span>
    </div>

在我的index.js中

define(
    [
        'jquery',
        'underscore',
        'knockout',
        'services/dataservice',
        'jquery-ui',
        'plugins/router',
        'durandal/app',
        'toastr'],
    function ($, _, ko, dataservice, jui, router, app, toastr) {
        "use strict";

        var
        // data
            tokenValue = ko.observable().extend({throttle: 500}),
            isAccessGranted = ko.observable(false),
            selectedCnksToTest = ko.observable(),
            possibleCnksToTest = ko.observableArray([]),
            selectedInterventationClass = ko.observable(1),
            possibleInterventionClasses = ko.observableArray([]),
            selectedLanguage = ko.observable("F"),
            possibleLanguage = ko.observableArray([]),
            resultRequest = ko.observable("cnks=&class=1&token="),
            subscriptions = [],
        // VM life-cycle
            activate = function () {
                subscriptions = [];
                selectedCnksToTest("1156090, 1555754, 1785013, 0299180, 0132571, 0050617, 0024208, 2926418, 0439216, 0072504, 1355957, 0458158, 1440585, 2578607, 0290601, 2595551, 1371483, 1402874, 1457563, 0633917, 0021915, 3007499, 2745115, 2582443, 2159838, 3004264, 2795995, 1510734, 2824753, 2889541, 1344431, 2180818, 4001137, 2602837, 2828283, 3110525, 3012259, 1356625, 2549624, 0067348, 0058669, 0379578, 0133918, 0036541, 2224657, 2660009, 1317809, 2055143, 0492983, 1670413, 1405570, 2275790, 2103935, 0057786, 0047761, 0054833, 1174952, 2114908, 2219590, 2308153, 2185437, 2082766, 1695147, 0062539, 1152768, 2964062, 2683340, 1057959, 2042851, 2209401, 0249573, 1077841, 0814707, 0249581, 0615096, 1183748, 2231140, 2121184, 2583110, 0031450, 4000238, 0031468, 2447779, 3094976, 0832923, 2318525, 0257741, 1434521, 1768894, 0084053, 2428258, 0849018, 1015288, 1524016, 2727204, 0614636, 1478510, 2876563, 0119511, 0834937");                //Fill in possible cnks to test
                //Fill in possible cnks to test
                possibleCnksToTest.push({text: "1156090, 1555754, 1785013, 0299180, 0132571, 0050617, 0024208, 2926418, 0439216, 0072504, 1355957, 0458158, 1440585, 2578607, 0290601, 2595551, 1371483, 1402874, 1457563, 0633917, 0021915, 3007499, 2745115, 2582443, 2159838, 3004264, 2795995, 1510734, 2824753, 2889541, 1344431, 2180818, 4001137, 2602837, 2828283, 3110525, 3012259, 1356625, 2549624, 0067348, 0058669, 0379578, 0133918, 0036541, 2224657, 2660009, 1317809, 2055143, 0492983, 1670413, 1405570, 2275790, 2103935, 0057786, 0047761, 0054833, 1174952, 2114908, 2219590, 2308153, 2185437, 2082766, 1695147, 0062539, 1152768, 2964062, 2683340, 1057959, 2042851, 2209401, 0249573, 1077841, 0814707, 0249581, 0615096, 1183748, 2231140, 2121184, 2583110, 0031450, 4000238, 0031468, 2447779, 3094976, 0832923, 2318525, 0257741, 1434521, 1768894, 0084053, 2428258, 0849018, 1015288, 1524016, 2727204, 0614636, 1478510, 2876563, 0119511, 0834937"});
                possibleCnksToTest.push({text: "0812792, 2339158, 0458141, 0085050, 0846410, 0075143, 0305870, 0127258, 1482959, 1256064, 1077916, 2125268, 0074849, 0107250, 0031781, 1722636, 1690809, 1478171, 2866663, 0075358, 0123075, 0082966, 2388700, 0050963, 0012468, 0670703, 2464964, 2195766, 2562858, 1405984, 0109207, 2647410, 2393015, 1150796, 0119495, 0027532, 3043155, 2159796, 2655561, 2760742, 1740083, 3019759, 2487825, 0102376, 2995777, 2314706, 2700094, 2445385, 0098285, 1484476, 2598340, 1643469, 0830141, 0073528, 0128348, 2883320, 2040400, 2393056, 0134429, 1497718, 1660240, 0869628, 1334499, 0043109, 1532431, 2826808, 1677624, 2899789, 2330728, 2120418, 0114009, 1371012, 0664151, 2886703, 2476240, 0033076, 2699296, 1455807, 2539849, 2371029, 3031903, 0090704, 0105288, 1608686, 2968212, 1238245, 2072627, 2582625, 2266930, 1563642, 0894873, 2285252, 0088278, 0808170, 0043570, 0095364, 1635010, 4001053, 0064618, 0034280"});
                possibleCnksToTest.push({text: "1367895, 1367903, 1578129, 1579341, 1088673, 1088681, 0016261, 0288399, 0251454, 1204379, 0017566, 0020214, 0100974, 1337286, 0100966, 0863290, 0447706, 2879344"});
                //Fill in possible intervention class
                possibleInterventionClasses.push({value: 1, text: "1 - cons-indicated"});
                possibleInterventionClasses.push({value: 2, text: "2 - cons-indicated when risk factors"});
                possibleInterventionClasses.push({value: 3, text: "3 - cons-indicated by caution"});
                possibleInterventionClasses.push({value: 4, text: "4 - concomitant usage not recommended"});
                possibleInterventionClasses.push({value: 5, text: "5 - monitoring required"});
                possibleInterventionClasses.push({value: 6, text: "6 - monitoring may be required"});
                possibleInterventionClasses.push({value: 7, text: "7 - monitoring by caution"});
                possibleInterventionClasses.push({value: 8, text: "8 - no measure to take"});
                //Fill in possible languages
                possibleLanguage.push({value: "F", text: "French"});
                possibleLanguage.push({value: "D", text: "Dutch"});
                possibleLanguage.push({value: "G", text: "German"});
            },
            compositionComplete = function () {
                subscriptions.push(tokenValue.subscribe(function () {
                    $.when(dataservice.getAccessStatus(tokenValue())).done(function (result) {
                        if (result.granted) {
                            isAccessGranted(true);
                            toastr.success('Your token is good.');
                        }
                        else {
                            isAccessGranted(false);
                            toastr.error('Your token is wrong.');
                        }
                    });
                }));
                subscriptions.push(selectedLanguage.subscribe(function () {
                    toastr.success(selectedLanguage());
                }));
            },
            deactivate = function () {
                subscriptions = [];
            },
            languageHasChanged = function(){
                toastr.success(selectedLanguage());
            }
            ;

        return {

            //variable
            possibleInterventionClasses: possibleInterventionClasses,
            selectedInterventationClass: selectedInterventationClass,
            possibleLanguage: possibleLanguage,
            selectedLanguage: selectedLanguage,
            possibleCnksToTest: possibleCnksToTest,
            selectedCnksToTest: selectedCnksToTest,
            tokenValue: tokenValue,
            resultRequest: resultRequest,
            isAccessGranted: isAccessGranted,
            //function
            languageHasChanged:languageHasChanged,

            //lifecycle
            activate: activate,
            compositionComplete: compositionComplete,
            deactivate: deactivate
        };
    });

郑重声明，如您所见，我订阅了我的 tokenValue observable，该订阅有效，并且设置如下 html

 <label for="token" class="col-xs-12 col-sm-3 control-label no-padding-left no-padding-right"></span>
                Token:</label>
            <div class="col-sm-9">
                <input id="token" type="text" data-bind="value: tokenValue, valueUpdate: 'keyup'"
                       class="col-xs-12 col-sm-5 margin-top-5"/>
                <span class="text-muted hidden-xs col-sm-12 no-padding-left">Insert the token used for authentication.</span>
            </div>

我确信 99% 的情况是，当我选择其他内容时，selectedLanguage 的值未设置，因为我在html 数据绑定(bind)和 toastr 应该附加可观察值的值出现，但为空。

我可以使用一些好的旧 jQuery 找到解决方法，但如果您能帮助我让这些订阅工作，我将不胜感激!

提前致谢!

Answer 1

你正在通过

optionsValue: 'key',

在数据绑定(bind)中，在数组上传递“值”

possibleLanguage.push({value: "F", text: "French"});