Communication between parent and child Lightning components during initialization

Question

I'm building a component structure of the kind

<c:parent>
   <c:child name="xyz" />
</c:parent>

and I need the parent to know about its children. Why, because the parent is displaying something for all the children. So I need it BEFORE that parent initializes itsself.

I thought I can do that by firing events on child initialization

<aura:component >
    <aura:attribute name="name" type="Integer" required="true" />
    <aura:registerEvent name="initialized" type="c:registerEvent" />
    <aura:handler name="init" value="{!this}" action="{!c.init}" />
</aura:component>

and handling them in the parent

<aura:component >
    <aura:attribute name="children" type="Object[]" default="[]" />

    <aura:handler name="initialized" event="registerEvent" action="{!c.register}"/>
    <aura:handler name="init" value="{!this}" action="{!c.init}" />
</aura:component>

Controller:

({
    register : function(component, event, helper) {
        var children = component.get("v.children");
        children.push({ "name": event.getParam("name") });
        component.set("v.children", children);           
    },

    init: function(component, event, helper) {
        var children = component.get("v.children");
        console.log("init " + children);
    }
})

Register never seems to be called in the parent. Maybe because the parent can't handle events before itsself is inititalized. But that would be to late.

How can I solve this? I read this great article Lightning Inter-Component Communication Patterns about the topic but couldn't find an answer.

UPDATE: The solution can be found in this question Lightning component event not fired or handled and its answer.

Answer 1

I would try to trigger an event from your outer component: "Hi there, I'm initialized". So now your inner components know they can register them self to the parent.

Answer 2

How about creating the children dynamically with $A.createComponent()? https://developer.salesforce.com/docs/atlas.en-us.lightning.meta/lightning/js_cb_dynamic_cmp_async.htm

Would that solve your issue?