如何处理这种循环依赖性？

Question

I have an design like this:

1. UI Layer
2. Component Layer.

The idea is all event handlers like click, painting the dom will be hitting UI layer, which will call the corresponding component layer.

Now imagine on click of a button, the ui layer calls component layer, so the dependencies looks like this:

define(['creationComponent']) //ui layer module

so that on click of button, this module can call creationComponent methods.

Now creationComponent too, in order to paint something, calls the ui layer, so the creationComponent looks like this:

define(['uiLayer']) //create module

and here I go with dependencies cycle, where I'm making mistake in the design process?

Answer 1

I do not think UI layer should really call component layer if some event happened. It should send an event. You could use Observer pattern here. After it sent an event, it should not care if it was handled or not.

When component needs to draw itself, I guess here an actual call should happen since this action can not be forgotten and its handling cannot be skipped.