I had tried to integrate knockout and the JQuery UI accordion and later the Bootstrap collapsible accordion. In both cases it worked, but I found that I had to implement a few workarounds to get everything to display correctly, especially when dynamically adding elements via knockout. The widgets mentioned aren't always aware of what is happening with regards to knockout and things can get messed up (div heights wrongly calculated etc...). Especially with the JQuery accordion it tends to rewrite the html as it sees fit, which can be a real pain.
So, I decided to make my own accordion widget using core JQuery and Knockout. Take a look at this working example: http://jsfiddle.net/matt_friedman/KXgPN/
Of course, using different markup and css this could be customized to whatever you need.
The nice thing is that it is entirely data driven and doesn't make any assumptions about layout beyond whatever css you decide to use. You'll notice that the markup is dead simple. This is just an example. It's meant to be customized.
Markup:
<div data-bind="foreach:groups" id="menu">
<div class="header" data-bind="text:name, accordion: openState, click: toggle"> </div>
<div class="items" data-bind="foreach:items">
<div data-bind="text:name"> </div>
</div>
</div>
Javascript:
ko.bindingHandlers.accordion = {
init: function (element, valueAccessor, allBindingsAccessor, viewModel, bindingContext) {
$(element).next().hide();
},
update: function (element, valueAccessor, allBindingsAccessor, viewModel, bindingContext) {
var slideUpTime = 300;
var slideDownTime = 400;
var openState = ko.utils.unwrapObservable(valueAccessor());
var focussed = openState.focussed;
var shouldOpen = openState.shouldOpen;
/*
* This following says that if this group is the one that has
* been clicked upon (gains focus) find the other groups and
* set them to unfocussed and close them.
*/
if (focussed) {
var clickedGroup = viewModel;
$.each(bindingContext.$root.groups(), function (idx, group) {
if (clickedGroup != group) {
group.openState({focussed: false, shouldOpen: false});
}
});
}
var dropDown = $(element).next();
if (focussed && shouldOpen) {
dropDown.slideDown(slideDownTime);
} else if (focussed && !shouldOpen) {
dropDown.slideUp(slideUpTime);
} else if (!focussed && !shouldOpen) {
dropDown.slideUp(slideUpTime);
}
}
};
function ViewModel() {
var self = this;
self.groups = ko.observableArray([]);
function Group(id, name) {
var self = this;
self.id = id;
self.name = name;
self.openState = ko.observable({focussed: false, shouldOpen: false});
self.items = ko.observableArray([]);
self.toggle = function (group, event) {
var shouldOpen = group.openState().shouldOpen;
self.openState({focussed: true, shouldOpen: !shouldOpen});
}
}
function Item(id, name) {
var self = this;
self.id = id;
self.name = name;
}
var g1 = new Group(1, "Group 1");
var g2 = new Group(2, "Group 2");
var g3 = new Group(3, "Group 3");
g1.items.push(new Item(1, "Item 1"));
g1.items.push(new Item(2, "Item 2"));
g2.items.push(new Item(3, "Item 3"));
g2.items.push(new Item(4, "Item 4"));
g2.items.push(new Item(5, "Item 5"));
g3.items.push(new Item(6, "Item 6"));
self.groups.push(g1);
self.groups.push(g2);
self.groups.push(g3);
}
ko.applyBindings(new ViewModel());
