knockout.js

For this situation you can do: <div data-bind=”attr: { ‘class’: selectedPriority}”> The only downside to this method is that it will set the class directly rather than toggle a class on or off, so if you are using multiple classes, then selectedPriority would need to contain the complete list of classes.

There are differences between them. The ko.toJS takes an object and “opens up” and cleans the object from all observables. It does this for the entire object graph. I behaves much like a serializer which means that you’ll run into problems if you have circular references for instance. It uses mapJsObjectGraph internally which is way … Read more

You can use the following trick: ko.computed(function() { return ko.toJSON(complexObject); }).subscribe(function() { // called whenever any of the properties of complexObject changes }); See http://jsfiddle.net/xcajt4qn/3/ The reason why this works is ko.toJSON will recursively read all the properties in the object, therefore making the computed depend on all the properties.

So, there are a few options that you have: KO will have an issue when you try to bind against undefined properties, unless they are off of an object. So, you can prefix your various bindings with $data. and KO will be able to parse your bindings. Sample: http://jsfiddle.net/rniemeyer/dLCL8/ If you know that several properties … Read more

Yes, you can call valueHasMutated function for your array: yourArray.valueHasMutated(); EDIT: If first didn’t help you can do ‘dirty’ refresh: self.refresh = function(){ var data = self.array().slice(0); self.array([]); self.array(data); }; Here is working fiddle: http://jsfiddle.net/vyshniakov/FuEy6/2/

Here is a thread with a few different techniques to keep the value numeric: https://groups.google.com/d/topic/knockoutjs/SPrzcgddoY4/discussion One option is to push this concern into your view model and create a numericObservable to use instead of a normal observable. It might look like: ko.numericObservable = function(initialValue) { var _actual = ko.observable(initialValue); var result = ko.dependentObservable({ read: function() … Read more

We do have ko.utils.arrayPushAll(array, valuesToPush) as a utility function that you can use. It is not available directly off of observableArrays though. If you add your pushAll to observableArrays, you would want to operate on the underlying array (this() in your case) and then call valueHasMutated() on the observableArray at the end. This will ensure … Read more

You need to use a create method on the mapping object itself like: var mapping = { //customize at the root level. create: function(options) { //first map the vm like normal var vm = ko.mapping.fromJS(options.data); //now manipulate the returned vm in any way that you like vm.someProperty = “test”; vm.someComputed = ko.computed(function() { return vm.first() … Read more

You can write something like this: <ul data-bind=”foreach: new Array(pages())”> <li data-bind=’text: $index()+1′></li> </ul> Here is working fiddle: http://jsfiddle.net/L8Uy5/