Question

I am working on an application and was doing something like this:

dojo.ready(
           function(){ require['dojo/parser','dijit/registry','dojo/on'],function(.....){
           //find a dijit and wrap it in event handling code.});

I was getting an error indicating that dojo was trying to register a widget with an id that was already in use. To solve the problem I entered this line of code:

           //before finding the dijit destroy the existing registry.

However, logically this prevents the next line from working because now no widget exists to which I can connect an event. How can I recover the dijit ids?

Answer 1

The best solution is to find out why your code is trying to register a widget with an id that is already in use and change it to not to do so.

The @mschr’s solution should work, but I would advise again using it, as it can break your code in many other places and you are likely to spend hours investigating strange behavior of your application.

Anyway, if you are willing to do it that way and automatically destroy widgets with the same ID, do not override registry.add() method. You could do it, but it does not mean, you should do it (especially in programming). Employ dojo/aspect instead to call a function that will destroy the widget with the same ID before registry.add() is called:

require([
    "dojo/aspect",
    "dijit/registry"
], function(
    aspect,
    registry
) {

    aspect.before(registry, "add", function(widget) {           
        if(registry.byId(widget.id)) {
            registry.byId(widget.id).destroy();
            // this warning can save you hours of debugging:
            console.warn("Widget with id==" + widget.id + " was destroyed to register a widget with the same id.");                    
        }
        return [widget];
    });

});

I was myself curious how to accomplish @mschr solution without that override, so I created an jsFiddle to experiment: http://jsfiddle.net/phusick/feXVT/