I am creating a web-component using VueJS 3, I want to expose a method on the component allowing the user to do something like this:
<custom-component id="x1" />
<script>
var component = document.getElementById("x1");
component.customMethod(); // as focus() method on native elements
</script>
If I define a method on the component, I can call the method inside the component. But the method is not available when I use it as a web-component.
//main.ts/js
import { defineCustomElement } from "vue"
import component from "./component.ce.vue"
const element = defineCustomElement(component );
customElements.define("custom-component ", element);
//component.ce.vue
const customMethod = () => { console.log("Executed"); }
How I can indicate to Vue Component Wrapper that the customMethod will be available outside the component?
In <script setup>, use the defineExpose() macro:
<script setup>
const customMethod = () => {⋯}
👇
defineExpose({ customMethod })
</script>
In the setup() hook, use the expose property of the context argument:
<script>
export default { 👇
setup(props, { expose }) {
const customMethod = () => {⋯}
👇
expose({ customMethod })
}
}
</script>
In the Options API, use the expose option:
<script>
export default {
👇
expose: ['customMethod'],
methods: {
customMethod() {⋯}
}
}
</script>
Currently (as of Vue 3.2.31), the only way to access the custom element's exposed properties is through its _instance.exposed property:
<!-- example/index.html -->
<body>
<custom-component id="x1"></custom-component>
<script>
const el = document.getElementById('x1')
👇
el._instance.exposed.customMethod()
</script>
</body>
Since _instance is a private property, use this solution with caution, as the property could be renamed/removed in a future release.