Here's an example: https://gist.run?id=0ade73e206476152944aea3f0b1b5e44
app.html
<template>
<require from="./modal"></require>
<modal>
<div slot="modalHeader">This is user provided header content.</div>
</modal>
</template>
app.js
export class App {
}
index.html
<!doctype html>
<html>
<head>
<title>Aurelia</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body aurelia-app>
<h1>Loading...</h1>
<script src="https://jdanyow.github.io/rjs-bundle/node_modules/requirejs/require.js"></script>
<script src="https://jdanyow.github.io/rjs-bundle/config.js"></script>
<script src="https://jdanyow.github.io/rjs-bundle/bundles/aurelia.js"></script>
<script src="https://jdanyow.github.io/rjs-bundle/bundles/babel.js"></script>
<script>
require(['aurelia-bootstrapper']);
</script>
</body>
</html>
modal.html
<template>
<div class="modal__header" show.bind="$slots.modalHeader.children.length">
<h1>Header:</h1>
<slot name="modalHeader"></slot>
</div>
<div class="modal__body">
<h1>Body:</h1>
<slot></slot>
</div>
<div class="modal__footer" show.bind="$slots.modalFooter.children.length">
<h1>Footer:</h1>
<slot name="modalFooter"></slot>
</div>
</template>
modal.js
export class ModalCustomElement {
static inject = [Element];
constructor(element) {
this.element = element;
}
attached() {
this.$slots = this.element.au.controller.view.slots;
console.log(this.$slots);
}
}