Question

I’m trying to create a widget that I can use with Knockout.js

I’ve taken the jquery demo widget for this example from here:

My code is in a fiddle here

What I am trying to do is to bind to a custom event within the object:

    this._trigger("random", event, colors)

so in my knockout binding I have this code:

ko.utils.registerEventHandler(element, "random", function (event) {
            alert("Got to here");
        });

I expected the alert to fire when the trigger is fired, but it doesn’t occur.

However if instead I bind to click.colorize as in this modified code then the alert does fire.

Can anyone explain why the triggered event isn’t picked up?

Answer 1

The solution is to set the widget’s eventPrefix – see here

 widgetEventPrefix: "color",

and then raise the event as before:

 this._trigger("foo");

catching it as follows:

 ko.utils.registerEventHandler(element, "colorfoo", function (event) {
        alert("Got to here");

Note the concatenation of “color” and “foo”.